Open Source Ecology Open Source Microfactory STEAM Camp, 7 Jul 2019

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From YouTube: Motors and Structural Calculations

Description

Motors - https://wiki.opensourceecology.org/wiki/OSE_Design_Manual_-_Motors

Structural Calculations - https://wiki.opensourceecology.org/wiki/OSE_Design_Manual_-_Structural_Calculations

Please review the Open Source Microafactory STEAM Camp here if you participated - https://wiki.opensourceecology.org/wiki/STEAM_Camp_Wrapup

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Recording started so, let's move on Motors: let's talk about motors, different types of motors for different sizes and forces and their limits, speed and speed and range of applications. How do you, how do you select the right motor for a correct application from electric to hydraulic to other?

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Let's talk about that and we'll focus here on design aspects where how do you build these things? How can you start building electrical or hydraulic or other motors? So let's talk about some basics. How motors motors work motors are rotary motion, so you can say rotary motion. Let me share the screen here.

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Roading rotary motion is an important concept, so motors provide rotary motions engines provide rotary motion. For example, a car wheel is a spinning rotor or a tool. That's cutting. Something is a spinning rotor, so rotors are everywhere in pumps and machines and just about everything, so it's important to have an understanding of how to manage them or or build them.

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There are different types of motors that were concerned about so we've talked about stepper motors electric motors, so stepper motors are electric motors with fine gradations that allow you to step at a very finite, well defined, well defined range, so that you can do precision motion, there's electric motors that just spin such as brushless and brushed DC or AC motors.

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There's hydraulic motors, there's water motors pneumatic, there's turbines as actually soft motors like flexible motors, so Motors is it refers to anything in the move, so so motion can be rotary or linear or other motor refers to its moving to serve various functions. Motors are typically reversible. A lot of motors are reversible, not all of them.

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Some depends how they're designed, but you can make make motors reversible like, for example, some hydraulic motors, so you can use them as a pump or as a motor some some electric motors you can use them, for example, a DC motor. You can use it as a as a motor that spins when you apply electricity or when you spin it it functions as a generator. So that's reversibility.

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Let's talk about a little bit about design considerations. Well, one of the main things to consider is is heat, because if you have motion- and you have rubbing- you can have heat and the stepper motors on the 3d printers they're, they have to be kept within a current range. Otherwise they overheat when you 3d print a motor one of the big considerations.

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There is the heating aspect, that's why motors are typically made out of metal, but you can also do it with plastic and if you know more about design when we, when we use motors, one of the main design considerations for using them is, whenever possible, use direct drive so, as least as little gearing as possible for whatever we do like like the direct drive, the universal axis on the tractor drive, for example, or if we're running a 3d printer axis there's when we move the belts on the universal axis, there is no intermediate thing: it's a direct drive over the belt of the belt, so you're trying to keep the transmission part to the to the minimum.

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We talked a little bit about the OAC universal controller and relays. The universal controller control panel for the 3d printer can also control not only the the stepper motors which which the stepper drivers on that board on the control plan are designed for. But if you simply do on/off operation, you can control other motives. How do you control a hydraulic motor with the control panel? You can you can use a hydraulic solenoid. A Sol annoyed with is a device that turns the fluid. That's in hydraulics like high pressure, oil or just water.

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You can use a solenoid valve like something in a in a washing machine to fill the water or to turn on a motor in a hydraulic system. Like a tractor, you can actuate some motion by using a hydraulic solenoid. What's the hydraulics all night, look like it's just Google that real quick.

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These are the typical hydraulic solenoids. We use for high pressure applications to turn a motor on and off they're about a hundred dollars a pop, so you connect electricity to it and it has a valve is basically a coil that gets electrified and moves a piston to allow fluid to flow. So this is for hydraulics.

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You can have a simple water, Sol annoyed water valve.

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That looks like like these, like these solenoids, like for a wash washing machine. This is not exactly that clear here. Water solenoids are simple: that's a water valve water saw and all.

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These are water solenoids, so you can control gases or fluids very easily with these low-cost parts at lower pressures for hydraulics, it's um around the hundred dollar mark for water and low pressure, it's around the ten dollar mark or under and gases are on the ten dollar mark.

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How do you control DC motors with the universal control panels, with with a relay like, for example, we? Now we use the solid state relay to control the heat bed? You can connect that to a big motor and use use that to control a motor. The only thing we can really control is brushless DC motors with it the control panel, as.

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Brushless motors require similar to stepper motors. They require pulses at a certain certain frequency, I'm sure, there's a an Arduino shield that we can use instead of the ramps shield, the ramps board that we use in our controller, let's let's, for example, Google- that real, quick, we'll, probably find an Arduino shield for brushless motor, probably.

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Sure does looks like there's several ones, there's one well, there's one for stepper motors or brushless DC brushless motor controllers shield for Arduino. So here some people are. Is that creating his own brushless motor controller shield? So you can see some open source versions here that works with Arduino called open. Vld, see I, haven't really heard about this. Yet I haven't looked into this much, but you can put on the Arduino that we have in the universal controller you can put on another shield to control, for example, brushless motors.

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If you want to control a car with the Arduino, you can, for example, control the speed, perhaps using the universal controller, with a shield. That's designed for brushless motors I'll, scalability considerations. When we talk about scalability of motors, a configuration that so so obviously get in large parts. But what about using modular components that you stack one on top of each other? What would that look like? So in a pancake.

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Configuration so.

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So, let's see it, let's, let's take a see what a pancake motor looks like they're flattened out. They are typically motors that have under pending what kind of motor you have, but but a pancake motor that has, it would be in an axial, no in axial flux motor. So where the magnetic fields run along the axis to spin the thing there's magnets and magnetic fields, the idea there is for stackability. Is you take a shaft and you take one pancake like that or you can connect multiple pancakes in order to scale scale.

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The force and I'll show an example with so, let's get into some examples of scalable brushless motor, here's.

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So, let's take a look at this from amazing DIY projects, but this is something you can get off-the-shelf right now, plans for this and we actually got these plans. But I'll take a look at this, so this is a an example of a brushless motor that you can Raziel only by yourself from this little design.

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Kid online cost you five bucks, but basically that's what it is. You've got batteries you've got a motor controller and as this device which has this is open sourcing that produces 500 watts, this is actually a good building block for what we would like to do. Look at this.

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It takes it actually generates, 500 watts it's about 72 percent efficient and it's fully DIY. So why do we like this? So this is a pancake design with a design of the magnets. It's basically a bunch of magnets on the ring, and he also has this open-source.

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Yeah I, this guy must know what he's doing, but here you have if.

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You look at those details. There.

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Of what this looks like that's, what is this, so these are MOSFETs, so field effect transistors. So they are the the units that handle power, so there's a couple of electronic components, but he has a little controller, a few discrete components that control this. This.

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Would say this is.

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Rather impressive because you get the plans online, so here it is, and you can see some pictures here if you, if you scale this up here, so basically these disks and he's putting magnets into there and then coils on top of those magnets, and you put a little sandwich of that together now in a pancake design. What.

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I, like about that, is.

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That you can stack multiples of this, so if you want to scale power, you put it in maybe a larger bearing on the inside the larger shaft, say one in shaft and two of these right. There are already a kilowatt, and that's I mean this is we're. Talking about a kilowatt is enough to run, for example our cutoff. So that's a that's about 15 amps, it's actually 15 amps is about.

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1800 watts.

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It's it's 15 times 120, so it's 120, plus 60, it's 1800 watts well so about three or four of these would match the power of an abrasive metal cutoff. So it's a lot of power there. But when I think about this.

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Like wow, this is scalable using just simple little twelve millimeter magnets neodymium magnets, which are very strong. So off this very simple design. You get 72 percent efficiency, that's not bad at all! For reference. Some motors that you get out there like, for example,.

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One of those fans they use these motors called shaded pole motors on fans they're only like thirty percent efficient. So this is almost competitive. With the best I mean the best motors are like ninety, five or so percent efficient, maybe higher, maybe up to like, like ninety eight, but this.

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This is at for, like a very simple.

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Very simple: build look.

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The specs so 5,000 rpm at 36 volts, so this is a DC system where he's using this electronic controller, a very simple one and this little board there that he describes.

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So if you want to get these plans, I actually got a copy of these. We.

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As we were trying to build this for this this session, because this this is not here- is very, very doable, you can think about 3d, printing, the actual and stuff cutting all this out from wood. Well, that's perfect for 3d printing you'd have to watch out for temperature thing temperature because you have to be careful. Are you getting your motor hot?

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Make sure that you don't have so much current that this is actually getting hot and melting, your plastic, but you can also do higher temperature plastic, like abs or or poly carbonate or other higher temperature plastics that you can completely do this so 3d, printing, simple, simple rings. This is the basic circuit. He shows you completely how to do it from discrete components, just doing a little breadboard and yeah. If you hear that thing, whirring, they're, no joke.

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A that's a relatively.

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Easy to build type of a design now, how are we doing on a free, CAD, brushless motor designer designed by William? Sorry, nothing there. Yet we need to work on that, but.

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That's a if we were to.

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Do this page here, we would start with that. Brushless. The the thing I just shows you as a starting point, because there it's working and it's 500 watts, which is no joke.

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How about water, water motors well, no hydraulic motors does that so we talked about designing these things. Here's.

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A nice video, so I do.

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Recommend this, this video of the hydraulic gear pump explained so.

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This guy explains.

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The inner workings of a hydraulic motor- this is a hydraulic pump and how you can turn that pump into a motor, actually making sure that the seals do not blow out Delma. No, how come back.

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See that in turn, be a hundred.

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Percent sure it's a video.

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But that's on a pump.

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There Simon housing out 250.

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Times, atmosphere but.

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Yeah yeah take a look at this video for cuz.

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Here what it means to be milling, those four things are metal in them ground, one efficient.

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They really develop. The motor has drawing this. The.

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Rotor so that when they get a house ordinary time, relief about shuttle, fiber learning subverts oil nice to be talking about so.

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You build hydraulic systems, you have about a religion, volunteers now.

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Getting at is an important trial operation that very timely.

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With a joystick and generate a mister.

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You can think about.

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Machine guns within yourself, the.

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Also exact time, net worth and I relatively.

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Not conceptually.

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Not too hard to do even have.

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Some rubber seals in there.

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I mentioned the others 3d.

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Printed stepper, motor and I really recommend this. This is pretty thing. I would call this pretty amazing work on this motor I show.

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This already before a small stepper.

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Motor with four electromagnets in the back and inside of it a split ring planetary gear that makes it spin, while the while the.

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Electromagnet has been very fast. We.

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Mentioned how you get like hundred or two hundred factor of speed reduction from the split ring planetary gear and this works here. So here are the 3d printed parts you can download. This is for regular NEMA 17 motor, all the different parts, and there you go definitely worth experimenting with so so maybe taking this I'm in contact with that's David, David, Hart cop.

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He says that the motors there get hot, so we'd have to work that out maybe put less current or you know, make different types of coils, but this is definitely worth worth developing further. So, let's talk about more so how you build? How do you build this? These kinds of things? So one is the 3d printed design for the pancake brushless motor.

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Well, it takes some work to do that. Basic specs, 500 watts, 2500 rpm 73% efficient to design it start. What I would recommend is start by building that one I'll get your plans for five dollars. The parts are maybe wild I, don't know 30 dollars for the mechanical parts or so.

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Is a another one.

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That it's a 3d printed electric motor by mr. Lima. So this is this.

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Is the advanced version, so this is like pretty.

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Precise engineering there's this 600 watt Halbach a rate, so it's a different configuration this motor here this one right here: let's click on that Instructables! This.

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Know where is that.

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Now, let's go straight to the YouTube video where he shows how to build this.

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This is a 3d printed Halbach here, a brushless motor, so this is printed with magnetic PLA printed. This is how the final product look.

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Like this looks.

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This is very well engineered, and this is what William.

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Actually built, he showed that we showed that the other day and.

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This thing was used to actually fly an aerial drone, so.

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This thing inspect they're all.

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Not bad I mean, but it's a common, very complex geometry. It's it's.

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It's got these linear magnets that go in there they're arranged at a particular orientation.

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So it's got this.

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Kind of a pattern of electrical trust.

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I'll have tell you the clincher.

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Of this, so you got the windings that you're winding this by hand.

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Is around magnetic.

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Pretty impressive all together- and this looks like whoa- this is so high interview. Well guess.

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Go back to our.

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Pancake brushless DC and the bottom line there is on the wiki page, it's about so the simple radial or the simple axial motor, the one, the pancake one.

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So this so let's compare the be side-by-side, so this pancake, which I which I showed on this website this one I made out of wood I, mean looks kind of gutter compared to this very fine Kristof lime erosion. But if you look at the specs, the amazing DIY project, one seems to be one-third: the cost and two times lower weight than other ones. So that's the difference between axial motors and radial motors, the Hal Baca Ray version. That's a radial motor meaning the magnetic fields go radially.

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The pancake one is where the fields, because the magnets are flat on the pancakes. It goes along the axis: it's an axial kind of a design, so you can have different designs of motors. These are two two possible ones, but what the point is that the simple pancake version with these flat magnets on these pancakes?

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Third, the cost and two times the lower weight, so they're powered ends more power dense than the nice exotic, how baccarat motor so for OSC we are. We are claiming we're saying this is the best candidate for all I, see right now. As far as the this pancake one, it's got usable power right now, it's relatively easy to build and it's low cost.

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So it's got some of the key considerations that you would like to build them, build an electric motor, so definitely worth playing I mean you can scale the magnets and rotors to be any size. You can control the speed through the electronic speed controller, because in brushless motors the commutation are switching between positive negative. That's what has to happen to promoter to spend here, your magnetite, your electrifying, the coils at a particular sequence, to make it spin, so you don't need Russia brushes. The brushes do not wear out in an example.

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So brushless motors are the more modern version which are much more longevity because you don't brushes that are wearing out and they can also be more efficient. So from the Aussie perspective, if we do that the incentive challenge on the cordless drill, we want to go towards the brushless motor right now. Some cordless drills have brushless motors. The more advanced ones actually have brushless motors a lot, a lot of them like when you see the sparks in the back.

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When you turn on the drill or another motor, the sparks is the brushes communicating or switching from one pole to the other and it's what causes sparks and that eventually wears out. These brushless motors are you're using the transistors to do the switching which calls no sparks, and you have a more advanced form of control that you have full speed control on these. So we can make.

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Ones for electric vehicles and so forth, so definitely worth pursuing how about some much other? Oh yeah, I, don't just want to show another things as a few. If we're making wind turbines slew bearings this guy, this is also Chris Christopher Lima. He may be slow, bearing so 3d printed fully 3d printed bearings with cylindrical rollers Wow. Look at that look.

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At the insides of that.

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So this is for for with with holding large axial loads along the axis, so, for example, in a wind turbine that you're trying to make this would be a so these all the rollers, your 3d print, and you put them at two angles: let's go to the very beginning, the way they go in these ball, these rollers they go at two angles, so they're they're worth holding a lot of force, basically a rolling rolling surface.

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So if you set up your printer with a very fine nozzle, you can actually print this in 3d and that's that's exactly what it looks like. So the race is the places where the rollers are they're slanted, and this has the property of withholding withstanding very high axial loads. So that's that's how it looks once it's closed up, but.

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So cool to print so take a look at that 3d print water motors, well, water hydraulic motors are available, but what about a simple water Motors? If you want to run motion through a let's show.

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The video this.

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Yeah look at this little video here, so you have a motor that you run water and it spins. It's fully 3d printed and note this one thing here, so this is a 3d print that you put an o-ring to make a watertight connection. Let me repeat that you put an o-ring, so plastic would leak, but if you put a rubber o-ring on this right there, you can put it into hope again and thing does not leak. So that's that. But this thing is a planetary gear.

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Gear drive, look at that another application of the planetary gear, you're, putting water into one side and you're spinning this thing with the power of water. So this is, you know you can make these water motors, which may be relevant. For example, like we talked about hydroponics or aquaponic towers that we that we have and say we're pumping water to feed the towers. Well, that water can be rotating those towers. How about that?

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And we can 3d print that so that's a great application for a water motor right now we could probably print water motors I would say like if you drill out fine internal surfaces and use all rings with of rubber. You can probably make 500 psi 3d printed, hydraulic valves and motors.

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Why do I say 500 psi I'm, saying 500 psi, because that gives you a tenfold safety factor of the over the strength of plastic, which is 5000 psi and up. So you can realistically say that, yes, for up to 500 psi, we can probably 3d print valves for hydraulics, hydraulic motors and valves now, as far as a 3,000 psi hydraulic motor, that's more metal territory, but if we can potentially use the like, we did in a universal axis for the two inch size we use metal plates around it.

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If you can be clever about how you're integrating metal with that, then you can withhold much higher forces. So then you try designing a 3000 psi hydraulic motor made of 3d printed parts and metal plates as an exercise for class. Also I, really like this there's a you: can 3d print this little turbine. Look at this thing, just a 3d print and you use that it has a bearing inside of it and the way you use it. I mean look at this thing: it's an actual working tool. How do you do that?

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Another side of it it's powered by a vacuum cleaner, so you put the vacuum hose on the other end, and that makes this thing spin, so you use it you're getting usable power right here. Look at that for cutting.

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At that, in a vacuum even sucks up the dust, how practical is that I actually didn't notice? That is awesome and I feel.

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I mean that thing is going fast, there's some be twenty thousand twelve. Sixty thousand.

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You have to kind.

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That this thing doesn't fly apart, but it's the motor inside that's moving inside a large plastic casing, so in principle, I, don't usually trying to show there, but just trying to show we have.

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The speed like when you know this is a one-year now so you're spinning a.

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Threaded shaft real fast.

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So now comparison to a dremel, how.

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Compare to this I, don't.

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Know, well, you can do this completely instead of a dremel. So this is an example of a really practical.

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3D printed part you can do right at home and avoid buying the adrenaline.

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You have to have a vacuum vacuum cleaner that provides suction, so these are metal.

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Parts I guess for what he has.

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Details of how you do this, but that's a bolt some bearings.

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And some other metal.

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Parts, so this is another example of metal plastic composites.

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About any tool, any.

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Tool is really metal and plastic and copper for the windings from electric motors and that thing spit screws.

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There you go so.

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I say this is a pretty clever.

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Instead of hundred thousand views on.

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Youtube so yeah, you need to call it element like that to hold a tool, so that's kind of tricky there. So how do we do that? Do.

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We actually have the full plans for this or.

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What's the description, do we have on the actual rotor, the actual.

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Let's see if we actually have, because because critical to this would be some information okay, so you have the 3d printed parts on Thingiverse and it's Creative Commons Attribution, so that's open source.

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But where do you get the the dremel? The bit holder.

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Proper bearings and accurate machine shaft, so high speed requires excellent Engineering's. The bearings are such-and-such.

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Yeah so this does I mean it doesn't. Look like there are ready, off-the-shelf parts to do this. He says here the shaft could be just six millimeter rod, but then a dremel style tool head requires a tricky 932 9/32 40-tooth per inch thread for the nut or maybe metric for other brands. Well, if you can find a threaded threaded, 42 teeth per inch, 9/32 inch shaft like a bolt. That's got that thread.

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You can do this I, don't I'm, not sure I haven't looked into this enough to see whether that is easily accessible or not should find it out, but yeah. That's a really nice practical tool. What about hydraulic robots? So this is soft motors.

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These are soft motors. So let's go right to the video here, this kind of a robot here. So let's take a look at the video what's happening here, but this is the power of 3d printing, so you're, actually, printing, these little cylinders and flexible. What's csail! That's! Where is that MIT, okay, so they're, ready printing these parts that are actually flexible, so water, there's water being pumped and these little little cylinders are there.

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So your 3d printing in multiple materials, in this case out of rigid, inflexible materials, so rubber and regular plastic and then water goes in there and extends the cylinders and that gear pumps to move a hydraulic fluid. Now that okay, there you saw a 3d printed. Is that 3d printed I'm, not sure it looks like that, might be 3d printed right there, but that's pretty cool, so you're driving that it's one of these peristaltic pumps, where, when you drive one where the other one spins and the liquidus pump through so.

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Maybe maybe different, so that's like that looks more. This one looks more like the standard hydraulic pump, but yeah look at that pumping from one chamber to another Belle's actuators. So that's rubber, printing, that's pretty cool. So this is how the legs move and then you actually end up with motion reel motion of this thing. So what it looks like it's a one print like one part print looks like they all printed that all at once, so soft materials can be printed. So this is rubber. Look at that. So this is your hydraulically actuated finger.

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So these are soft robots like soft grippers like if you want to make a humanoid robot use these soft 3d prints and fill that with air or water to move those fingers back and forth, and that was back in 2016. So maybe a couple more: oh yeah! So yeah, that's that's it for Morrison. So you can see that out of this we get really nice electrical motor possibilities with the pancake scalable motors, and then you can 3d print the those as well.

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So the leading candidate is a 3d printed, pancake style, axial, brushless, DC motor, that's I, think the main outcome of this and then the 3d printed turbine I also like that as a practical tool for the dremel tool aspect. So, let's move on to the second part of this saw and since we're at it. This is our last last day of adventures here people so oh yeah I need to see more more videos and how people are making Dremel tools on youtube.

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So look that up they'll be very worthwhile to document the full build of it like, for example, in the former turbine. We saw that oh it's tricky basically was like. Oh, if you're gonna get that that threaded balled, you have to machine it precisely so you know that's not exactly accessible, but maybe we could find something: that's more accessible using standard, off-the-shelf parts like a bolt that has the right thread and you can put a with a dremel yeah. It's just figuring it out banging outs on the detail, how you mound the metal parts?

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How do you hold the bit? How do you hold? What's the Chuck for this look like so Chuck Sarah, you know like lathe, chalks or drill bit chucks or chucks for holding little tool bits like here. That's uh that's like the hard part of this, and it's also gonna be a challenge for us. What are we doing a cordless drill? What kind of Chuck are we gonna do? Are we just gonna buy one off the shelf? Are we gonna try to make it ourselves or how I don't know how that's gonna evolve right now?

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Okay, so that's the motor design guide so now I'm gonna go to the design is in the last lesson is something about conceptual design of structures, so understanding structures. So that's gonna be lesson number eighteen and the last one. In this series we don't have the time for the thermal calculations here, so structural calculation is just understanding basis, basics of forces and different materials and what what can withstand what for structures like frames, foundations or roofs and and other other structures? So what are structural calculations?

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So you need to understand some basics for determining how structures work, how much they will deflect when a certain force is put upon them, and how do you? How do you determine that a lot of times like, for example, the universal axis you're talking about the axis deflecting after a certain force, so you can actually figure it out. There's online deflection calculators where you can say: okay, I have a shaft so long and it's so thick and I'm pressing on the end of it with so much force.

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How much is it actually gonna deflect, so you can start with that kind of analysis and the first principles if you know how to use free cab, the finite element analysis on freecad that feature is there, so we can apply here's a application of a given load and you draw say a tube or whatever, like a two inch shaft you apply the load in a certain location and freecad will tell you how much that will deflect. So there are tools available to do this. Let's take a look at some concepts.

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First, though, so flat wobbly things so a flat bar like a piece of lumber, the lengthwise of it when you hold it on your shoulder, will just wobble up and down like like flats or not stiff in any way that will completely wobble. So you want to put them on an edge to make it more stiff. But when you design things you never ever want to really leave any any parts there.

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Just one flat like, for example, the frame that we're doing it's an angle, you're bonding two of those together, so they cannot flex while one bar, you can kind of like push it up and down once you attach and turn it into an angle. It becomes super stiff. So if you're designing a bench like we saw for the saved on open-source golf card, you don't want to use use flats there. You would always want to use angles.

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So, if we're using flats, if you're using flats put them at a right angle to each other as well, then like we do in the frame for the D 3d printer or for the large large aunt mill that we're building right now so flat wobbly things flat things flat. Structures are wobbly in the direction that got a flat direction, it'll just wobble up and down. So you want to use right angles and gussets. What's Augusta, the gusset is essentially a reinforcement like a triangular. Let's look at what a gusset is gusset.

A

You always want to remove the flatness so images. Let's look at some images. These are gussets like this thing, this little reinforcing thing. So, first of all, here we have a right angle, and you reinforce it like like this here to prevent this from bending further. So gussets are a very common thing that we want to use in various applications.

A

Trusses, so what our trusses trusses are common here, because trusses you might want to use a truss in a house. A truss could be as simple as.

A

So you gotta trusses, look at triangulated structures, so, instead of having one member like one member that can bend easily, if you extend its vertical height and put triangles in between it, that's that's essentially the trust shape it's a very much more stiff shape. It's much more than a to to individual beams here like in this picture, so trusses are where you've got triangulation happening and stiffening up of the structure, because the most stable structure is a is a triangle.

A

You cannot move a triangle you can I could bend it because that fit fixed-lens that won't wobble on you if it's connected solidly on on that corners. So this is a very common way to do things instead of a trust like this. Instead of using this, you can use plywood or like wood, that's solid, but it has to have that depth at that height to it in order to be stiff in the vertical direction. Now this truss here would still wobble in the direction like going into the truss.

A

So while this will get you real stability on downward forces, this one I'm pointing to here it'll still wobble. If you press like, if you're pressing into the page here that would still wobble so trusses the way they're made, that you'd might want to include a three-dimensional space frame kind of style truss. So this will not. This will not move on you going vertically and then horizontally. If you push into it, because it's reinforced in those two directions, because a trusts like this is essentially what I described before it's a flat in one direction.

A

So in a direction where it's flat perpendicular to that direction, when you press on it'll, just just bend on you, trusses are important because we want to span, make large spans and houses like say 16 feet or so so. Foundations and wall weight loads, so relevant to our work is say: we're building the micro house in Belize. We have to design a foundation.

A

I've got a page on on on a wiki called, but let's see if we have an open-source foundation because I basically put attached them numbers to it to show okay, what kind of weight will concrete with rebar in it withstand like? What's the open source business foundation? No, that's a different type of a foundation, no can't find it here, but on.

B

One of the the micro house for.

A

Which we did so probably we want to go to micro house for on the wiki and look at what we did for the trusses for the foundation there. So this is actually that's. That's what the place looks like when it's cleaned up right now we're using that as part of the workshop space, but that's another house there, so the design document now where's the design document build instructionals version history.

A

We have a document there which talks about foundations. Essentially, do we have a foundation here there? It is so we go to the foundation part.

A

Also foundation here taking some time to load again, there's some speed so.

C

That's the foundation.

A

Now this we put bricks upon it. The question is: how much weight can this foundation withstand? If can't? But so you have to consider properties of concrete, you have to consider the weight of the brick brick walls. Also, these are actually instructionals for mullis's. Just build information here, but concrete is about 3000 pounds per square inch. In other words, if you have, if you had solid ground like it, was rock-hard he put this on a rock, then that concrete could withstand 3000 pounds of force per square inch. How will that hold a brick wall?

A

Well, the brick wall is about 200 block each 20 pounds so 200 times 20 this 4000, it's 2 tons per 4 by 8 foot wall section, so you got about 4,000 pounds. The strength of concrete is 3,000 psi yeah that should hold, because each square inch of concrete can hold up to 3000 and compression.

A

Now the foundation is like this to me. We have rebar going through it because when you put all this weight on the ground to ground my compress a little more in one place than another concrete is not great. On unbending. Like you can crack it easily, so so you put rebar through this and we have a couple of strands of rebar going through this to make this make this happen. But I did some basic calculations on what what the strength of this foundation should be.

A

How much should it withhold simply by taking okay, here's the PSI, if you put a rebar through it, that's how much bending how much tensile strength it could could retain and I can't find it right now, but I can add a link later, so you can take a look at those calculations, but basically in this, the bottom line here is we're just using six inches of con greed and forms on a gravel, gravel pad, and that's sufficient for this.

A

This foundation here in terms of structural strength, not exactly sure if, if that is called compliant, I was not able so far to get any engineer to look at those calculations and approve them. We had no often a structural engineer. Let us know we can review this on the wind loads. So let's talk about wind loads, just a little bit for any of these quantities. Here you want to go to online calculators like how much force like if you have a house, how much wind load can it withstand.

A

So you, if you have a certain area of a wall, a wind at a certain velocity. What's the force on that wall? Well, you can calculate as the mass of the the width wind times velocity squared, that's essentially yet so the density times the area times velocity squared time is 1/2. So that's Formula one right. There basically says Rho is the density density times the area get you the mass about.

A

So you can study that equation, but you don't necessarily need to study if you plug in values like air density is 1.2 kilograms per meter, cubed I'll say a wind speed of we have a hurricane here. You've got 60 miles per hour, and our wall here for hab lab for the front is say like 50 meters by 2 meters, so like 30 meters, there 30 square meters, no it's more than that. Like 3 meters high, that's like 10 feet almost times 3 times to about 30 square meters. Only 30 40 is about 40 square meters.

A

So, what's the force on the you just hit calculate and tells you the the wind load is gonna, be 8.

A

86,400 Newtons, what are mutants Newtons are like kilogram force. So you divided, you can Google one a Newton this, but a Newton is a point one of a kilogram force, so you look at Newton is like Newton to kilogram force converter online, and you see that okay, one Newton, is about 1.1 kilograms. What we're saying here in this calculator we just did we have 86,000 Newton's. So it's about 8,000 kilograms of force.

A

That's a lot, so we can say that a hurricane with its like it's a lot of weight, so probably the Brooks that we have here might be able to do with standard I think they would but yeah. This is that that's a reasonable amount, like 8,000 kilograms. Man, that's a lot, but that's all spread over the entire surface. Like it's a long front.

D

What property of the bricks would you calculate in there where they mount the wall would stand up? I would.

A

Say it's mass because it's really how a firm that mass is standing there and how well is it anchored to the roof? Because if you cannot move if the roof is well anchored that it's like moving the entire building, so that's where the the roof, the bond beam towards the roof and the rest of the structure. If that is solid yeah you can I mean eight thousand pounds. You know a piece of lumber like and a four by four lumber. You can google that how much can huh how.

C

A

Four by four lumber post hold: it's probably like a thousand pounds or more more than that. Let's see.

A

And 4x4 posts yeah now I'm not getting in the other hand, but but yeah eight thousand kilos of force- that's quite a bit, but if your structure, we said that, like one wall section, is already four thousand, it's two thousand kilos so for wool. Sections weigh about that. Much so you'd have to push it with a force equivalent to its weight for like four wool sections, so kind of think about that again we might be able to do it depends. Maybe the windows would would crack at that pressure, but it's spread over the large area.

A

So you can take a look at like each square meter. If that's well, I think it's quite useful to not look at okay, that's the whole side. Let's look at like maybe one one square meter which is quite manageable to think about. So if we had the value of eight thousand kilograms, when we had forty meters, it looks more reasonable. Oh that's, 200 pounds, 200 kilograms: wait! Is it 200 times 40, 200 kilograms per square meter?

A

That's a lot but I think if the wall is like 2,000 kilograms per section, I think you can I think you could handle 200 kilograms or suggest by its very sheer mass. So that sounds sounds good to me. Sounds like yeah we'd be okay, I'm 60 miles per hour.

A

Okay, wind loads, beam, deflection, calculators, so beam deflection, I mentioned at it, and that's a really important thing because for the universal axis are like the even looking at a rectangular beam like saving up some kind of a framework angle like an angle, while angle is not a beam, but you can probably try looking for like angle iron deflection, calculation, that's more like freecad finite element, analysis territory, but at least for shafts you've got a decent idea and if you want to say okay, so you have access to a beam deflection calculator.

A

You can maybe compare that to angle deflection. So what I would do in that case like if you're trying to say okay? How much will this angle you're just trying to get a rough in your head? I would take a look at for this angle. What's the meat of that angle compared to in terms of like what would that be? If it's a quarter by say it's a half by four angle, what would the equivalent rod be? Maybe it would be like two by two inch rod at about or so I.

A

Don't know how much mass is there enough in the length of rod versus the angle, the nice big angle, so what I would do is if I were to get them. It's not going to be accurate, but the first first-order approximation would be. You look at okay, what's the equivalent beam just around to look like for that, for that amount of metal and and look up, look that up in a beam, deflection table or calculator. That's online to make a first thing.

A

First order, approximation to what your frame would deflect if you gave it a certain force so like. If we're looking at our Universal axis, we can compare a beam deflection by approximating that the angle iron, the amount of weight master's in that's in there a round beam, so that's they'll be first order approximation.

A

Let's talk about hollow versus hollow long things versus solid long things, so tubes tubes versus solid shafts. So let me ask you this: at a torch table, we did. We had one inch, solid shaft, and then we used pipe.

A

That was just type those hollow well, it turned out that the one-inch shafts would Bend under their own weight and then the hollow pipe would be totally stiff. Well, what's that like? How do you explain that? Does it mean that the how hype this is stronger than a solid pipe because of its geometry? What's the answer there, he.

D

Just doesn't have to support as much it.

C

Has more strength.

D

Per unit weight, yeah.

A

Yeah it does, it does so it doesn't deflect, but then does it mean that it doesn't mean that the hollow shaft is stronger right. No, no.

D

It does it, it doesn't because.

A

It doesn't have as much much of its.

D

I wonder if like could be difference in in the mass of that to ever overcome the additional strength you get by filling in the hole on it. Yeah, hey, I, wonder if you.

A

Know it would have I mean that's that's the implication, because when we did a tour stable, the solid shafts would bend down quite a bit, so the gravity effect of that is providing an undesirable effect. But then the second question is what, if you have the same amount of mass per weight in a tubular shape versus a rod shape. So if it's hollow, then the same amount of mass will make for a larger right so which one will be stronger in terms of ability to bend. That thing down.

D

A

Yeah, the tube will definitely be stronger, so so.

D

A

Tubular objects is much more efficient from material use perspective if you're designing from scratch. If you, if you're thinking about a say you say, you've, got your metal rolling infrastructure in place, you want to make the strongest structure for the least metal you want to make pipes. Also, if we're making axis for the universal axis- and we had say our you know- 10 or 20 pounds per foot, it's about 15 pounds per foot for our universal axis right now. If you had that weight, you probably want to make like a large, larger tube.

A

So it actually is structurally stronger because of its geometry. Yeah. The.

D

In the workshop there's a number of kind of square tubes yeah and wondering where you got those from I think he said you maybe had the customer to them or something they got all the holes punched in it.

A

Well, those holes are actually cut by laser, so that's a basically regular off-the-shelf tubes and we sent it to a fab shop to get the holes laser cut and that that creates our modular construction system and that's a it's essentially box beam and I mention it. There's a nice book out there that, when I started thinking about this a long time ago, from a couple of decades box, beam source book Google that box beam source book, it's a book by Phil jarvik Jorgenson. He talks about us.

A

Let's, maybe look at some images on the internet for that. He shows us how to build like furniture. Various structures like even this kind of a car out of box beam, basically X Y Z corner bolted structures. You can do a lot with that. I'm, not seeing some reason that seeing much on that well yeah this kind of stuff, where you got the frames that are just tubes with holes. It's been used a lot with wood, we're using that with steel.

A

There's, four structures, actual structures with bolts, where one inch bolts have tens of thousands of clamp strength. So you can make very solid corners and then XYZ kind of system also yeah take a look at a book. That's pretty interesting.

A

A

Those box beams sourcebook also so say we end up making steel at one point: is it manageable by I mean steel is really strong? Are we gonna have enough power to no strength and the rollers to roll that steel? Well, if it's cold I mean that's 50,000 pounds per square inch.

A

So if you're gonna indent into that, if they're all runny it's, it could be hundreds of thousands of pounds of force, but that's where you take the temperature up, so the idea melting and the force completely reduces, and if it's almost liquid, the force is negligible. So when you get it have this, what it's called hot rolling you want to do it at high temperature, so the force of the rollers is completely Amanda's. We can roll it like butter or spaghetti. My.

D

Question kind of about that process of rolling is it possible to like have a system where you have rollers that are supposed to you? Have rollers made of steel and have yes.

C

D

Steel stock and you heat up the stock and you keep the rollers cold. Can you roll, like you, use one this one material to roll the same material as long as you in those I'm to keep the one hot and one cold, I? Think.

A

So I mean you be so so the rollers pass over the stock, that's hot, so you're gonna pick up like the big stock that you're rolling is gonna keep hot because the rollers are smaller. But yes, the rollers are going to get really hot. So typically those processes, they're water, cool, there's coolant somehow because otherwise they get as hot as the steel and you like wear out the bearings or whatever you got in there right.

D

Yeah I mean it just used to be like with some of these things. Difficulty is you it's.

C

D

The same material for shaping the same material like yeah.

B

You wouldn't you'd make an honor the same.

A

Material you'd make the rollers would be harder than steel. Well,.

D

I mean I guess to be. The problem is that you eventually Iran avartar things and so like if you're, if you're specific you're doing all of the same, like if you're doing all of your own stuff you you.

E

Want to propel you.

D

Want to have the.

A

D

Of using what you have to shape more of what's.

A

Right so in that limit what happens? Well, if the one part is that like 1,000 Celsius, which is near melting and the other one, is kept like a few hundred Celsius, it's gonna be way harder, so you can probably roll with the same material that I didn't think about with yeah. That's right had the hardest metal that you can roll, maybe I, don't know. Maybe for some metals like tungsten, I, don't know, I, don't know if tungsten is rollable or whatever I they're the super hard metals I actually don't know how to do it.

A

But for steel, it's pretty easy to find things harder than your normal steel.

D

Fun little thing: I've seen on YouTube debates, there's massive hammers yeah.

B

This dealer, hammering.

D

Is really hot, but it looks like the hammer itself is pretty cool yeah.

A

Yeah, that's more like getting into the forging where we have. We did include the forge initially, because that's a common, very common thing, like even hammering something on an anvil, is a forge operation. So we have that in a set, so structural structures that we're concerned about is a lot about frames. We talked about the universal frame.

A

Other thing to consider that's worth doing is concrete beds for CNC machines, because concrete is so heavy, so strong and so inexpensive, so that in high force machining like say, the next iteration are the the higher torque version of the heavy duty mill that we're doing like what we're doing right now is like an intermediate intermediate duty mill. But if you want to go higher force even then, we probably might still say they leave the base and put like bolts in there put just throw concrete and they leave like a bed.

A

Where have a lot of structure, that's embedded in concrete, that's a common thing to do. People people do that in C and heavy-duty CNC machines with concrete beds, environmental considerations. So we talked about structures a lot of times.

A

You want to concern yourself, like I, think the number one elements you need to consider structurally is heat like if we talked about machines, for example, on a 3d printer, the motors were running a little hot well, first of all, they could break, but they can also melt the plastic that they're on, like once they get to like night. Stepper motors are rated for 80 Celsius, but if you're doing working with PLA and that's that PA is gonna start getting almost soft and those temperatures. So you have to consider, for example, on extruder motor.

A

If it's got this small bracket, that's attached to, maybe PLA will work, but it might be that you need a higher temperature plastic there. If you're doing a printing the motor in bracket so pay attention to he'd like, for example, heat on hydraulics, which goes to 180 Fahrenheit. You don't want to have any parts that are meltable like plastics and hydraulics are not really compatible.

A

Well, about heat things, get weak with heat, so for plastic, that's in the order of a hundred Celsius for metals if they get to hundreds, hundreds of degrees or thousands and close to melting point, I mean they lose all their strength. So that's a consideration. You need to make when you're designing something like an induction furnace.

A

If you cannot make a crucible out of steel for melting steel, this is the crucible, would melt, I mean the crucible can hold the metal and it will conduct the heat and an induction furnace well, but it will melt so you have to be careful about heat effect.

A

Yeah. Another thing is oxidation or reaction of when you talk about environmental effects on on structures. If it's steel, steel does oxidize over time, when you use thick steel sections, then it takes really long for them to oxidize, but they still do. Aluminum tends to is better than that, because it reduces a self-protecting oxide layer that oxygen no longer penetrates deeper in so depending what material you have. You have to consider corrosion and environmental considerations or a skin acids.

A

If you get acid rain or if it's in contact with the ground, which may be basic or acidic, you know, things will corrode much more in the presence of water, so water, which, unless you've got plastics many metals, typically corrode. So you got to protect them analysis tools, there's a lot of tables out online.

A

If you want to think about structures like say you want to design you build in the house and you look at what spacing do I need for my my roof members, or something like that so tables like when you're starting thinking about design and you know know, know structural engineering. You can start start by looking at table for many things from things like pipe tables for pressures like if you're designing a hydraulic system. You look up a you know, common thing that I look up.

A

A lot is okay, pipe pressure pressure table, say we wanna run hydraulic fluid power and pipes. Well, what can a steel pipe hold? That's when you have to go into perhaps heavier steel pipe, like maybe the there's gauges of steel pipe like 440 schedule, 40, it's called schedule a deist. Have you all the schedule 160, which is super heavy? They got they get up to like triple heavy walls but like, for example, I want to use in this table. Uh-Huh 1/2 inch schedule 40 pipe. The working pressure is 2,000 psi 2,300 psi.

A

Well, that means that would be able to burst if your hydraulic system is 3000 psi that won't hold it now half inch schedule. 80 has a working pressure of 4100.

B

A

A burst pressure of 21,000, so that probably will work but I you have to look at tables if you're working with extreme pressure or force tables such as pipe tables are very useful, so there's tables for everything like wall thicknesses of pipes. That gets you dimensions and possibly stress like PVC, let's say working with PVC for water systems. You want to know how much? What's the limit of that we talked a lot about bulk, clamp strength where we can Google a bolt bolt struck, bolt, clamps strength table.

A

So take a look at that you can, if you you'll, say mounting our Universal axis with quarter inch bolts well, can they hold 200 pounds? Okay, tell me the answers. Let's look up, we've got a bolt strength table so we'd say we use quarter inch, which is what we're doing six six millimeter, not at bolt Depot or let's do a table bolt shear like say, you're hanging, something on a bolt when will it shear?

A

So what's that for for a quarter inch I would say that's I'd say it's thousand pounds because the metal is pretty strong. Let's see, let's see what it is in real life, let's find a bolt strength table.

A

We got quarter-inch right here. Point two: five great Fox, this is only great fighter, doesn't have great but quarter-inch says.

A

Shear compatibilities: oh wow, a quarter-inch bolt shears at 4,000 pounds at grade five. It might be like 3,000. Those things are strong, so yeah, no problem, you can definitely use quarter inch bolts for the universal axis and on the universal axis you might want to design for peak loads which we're designing it around to 200 the peak load. We talked about peak loads on anything.

A

The number one thing to say is like 10x like you might get an end sudden impulse like something drops or Falls or you something hits like something goes against the dead stop. You want to consider typically about 10 X Factor. So if the bolt there was say 4,000 at 3000, if the force that were typically working with us say, 210 X is 2,000. So yes, that that quarter-inch bolt is within a good safety margin of what we want to do in our system.

A

I think we're not going to get this access to fall off when we're machining with it and come into some emergency condition. Besides, we've got several of those bolts right. We've got like four or eight four axis, so we're pretty much sure that it will work so bolt. Strength tables are important. Another relevant thing very practical for us is how we stabilize brick walls to make them hurricane earthquake-proof, and for that we actually use a through tie.

A

We we put metal mesh or fiberglass match they actually have this new product, we're just talking about that with Scott for the Belize build, but a layer of mesh on each side, that's through tied through the wall, so we actually put when you build the wall you're putting in metal ties just metal wire, then you're tying the mesh around each side, so that makes it super stiff like it can't pull over, because one side is holding the other. That's that's actually the state of our technique for CB construction. So that's a great structural principle.

A

If you want to build earthquake proof there you go, you can look at, let's see what it what it has for double basket: I'm, not sure we're gonna find a technique for CB construction. I mean there's not a lot. I can see the construction of this I'm, not sure we're gonna find this best practices. Oh, it comes out best practices.

A

Yeah, don't really see here a lot of people just use a rebar through the wall with hollow block, but that's no idea: some tests have been done. It snowing years, the double bass of the basket technique with with laughs or mesh metal mesh on each side. That's how you'd you'd want to do that. Oh let's see so. Let's talk about finally freak out our favorite tool here and talk about some exercises that we can just think about. How do we go about solving certain certain structural problems?

A

So, first of all, we've got the finite element, modeling workbench and freak out, which is which is there and what you do there. There's a nice diagram there of how this works. So, if you want to analyze some structure, what happens? You've got a solid object and then you want to do analysis. First, you convert that object into a mesh. You can use G mesh or net Jen. These are all open source program that programs that freecad has built in so once again, this is the power of open source modular design.

A

Freaking think all these uses these calculation programs because they're open source and then we have the to do finite element. Modeling, you have a solver, so that's how you solve the equations. There's nice ones like calculus is the AEA elmer, and then you have a results for visualization, actually wanted to show you some of these. So first you break it up into a mesh. There's this open source software that converts an object into a mesh, basically a bunch of triangle approximations. So you can calculate the forces between that that's G mesh.

A

Another one is net Jen. These are all like GPL open source LGPL license. This is used to imagine so those links are all in the document there for now for getting into the solving of the equations for force, which you have to understand. The forces of the equations to be able to use this because there's an interface allows you to bypass that. So, for example, is the 88 finite element. Modeling software license the GNU GPL.

A

So that's awesome finite element from the University of Bayreuth in Germany, there's calculus another package, another package that allows you to do various simulations like okay. This would be loads on the tips of a turbine like a little turbine. You want to make put them into freecad run this I haven't used. This I can't tell you the details of how to do it, but typically what you do is you put like an arrow saying: you've got a load there, so for say a beam like you put on a draw beam.

A

You draw an arrow there and it tells you how much it would deflect. So it's as simple as that, conceptually I, think that's that's something. That's well within the reach of the a user, perhaps a power user of freecad, there's Elmer, there's another solver, so you've got once again. You got your triangle meshes that you then perform calculations on to get forces of this propagator objects, and then you visualize, so there's programs like Power View, scientific visualization and that's the website for paraview.

A

But that's the cool thing is: you've, got all these advanced tools, plugging right into freecad, because they're, open-source and they're usable, of course, there's many other proprietary ones which I will not go into because I don't particularly have interested in it, but I should what I should know? Is the industry standards like what are the features that are in the and the professional packages, the so-called industry standards versus? Maybe these open source ones? Are they limited in any way? Or can we do just about everything that can be done? I'm sure it's!

A

These are some like calculus, that's it's a powerful package, but I cannot tell you what what exactly is missing right now, I haven't studied it enough. So some exercises for you. If you want to start getting busy doing some understanding structures, you can look at one concept is isotropic versus anisotropic materials like lumber. Is the direction will be stronger in one direction than another, but you can use that principle and looking up, ok, say the tensile strength of one or the compressive strength of Lutie.

A

You can tell me, then: oh, how much will a 4x4 lumber post support I, know the answer right now, but the process would be to look at compressive strength of wood for for a given dimension. What what is it per per square inch? And then you say, okay for a 4x4 has 16 square inches. How much will that hold before it actually collapses on you or.

B

A

Much pressure can a quarter-inch wall pipe hold well, I would start with that say it's a metal pipe I would just take a look at the structural strength of pipe well that that no that's kind of getting a little hard. So I want to look that up in a table. They want to calculate if you can just look at that's the easiest answer, I kind of tricked you there to start to look at okay. What's the calculation? Well, it's a quarter, inch wall.

A

You know it's like 50,000 psi for the wall, but if it's only a quarter inch, how do you well? How do you think about so look it up on the table? Don't worry about the math or how much pressure can a 1/8 inch rubber hose hold.

A

Yeah, this is where it worst on where we're, but we don't have a computer to share it on the screen here or how fast will a table saw cut wood I think the answer for the rubber hose would be to look at some tables like rubber, hose pressure limits. Just look it up, it's like plain rubber, let's say or like.

A

If you, if I think about like an inch thick piece of rubber, we know that the rubber is like 5,000 psi and I've got a one inch thickness and there's a window of that 1 inch rubber. How much would hole like five thousand? It's pretty simple. It's one inch. The syringe is five thousand pounds per square inch. There you go, so you can look at these basic hand-waving calculations to get you the first idea, and then you can actually look at more detail or how fast a little table saw cut wood.

A

Well, you can take a look at and say how much force does the teeth does the 200 laid have and what is the the strength, the strength of wood and you compare those two values and then you will be able to say okay if that piece of wood is fed at a certain rate, you'd have to compare the strength of the wood to the strength of the blade eating it up say the blade is the got like 10,000 pounds of force or something I don't know whatever it does, and the wood is like say a thousand pounds per square inch.

A

Then, with ten thousand pounds you might be yeah. It depends on your feet right. How fast are you feeding it, but you can take a look at weather. Okay, is that force going to be sufficient? It has to be greater than the strength of the wood in order for you to cut I'm kind of giving like hand-waving arguments here. How much force is required to mill for a mill to cut point, zero, 1, inch, chips and steel? That's kind of like a pretty tricky question.

A

Well, assume you have steel at about 50,000 psi, you're eating away point zero, one chips and steel. Well, that's one hundredth of a chip so say like the amount you wear out is like a fraction that fraction of a square. So you measure that area of that and I would say, divide fifty thousand pounds per square inch like by the fraction fraction of a square inch that you took away like say.

A

If you took like one hundredth of or 1000 with one bite that you just taking very tiny bites, you took out 1,000 square inch with one bite and you've got 50,000 psi steel. That means each revolution has has to have like 50 pounds of force going in that so that it has to if it's yeah, so you can kind of make basic ideas of calculations. What forces are involved.

A

A

Yeah, can you guys you guys still hear us remotely? Are you guys logged off I, don't know no I'm recording. All of this, it looks like Network problem occurred so by I'm recording this. So you can review this or, for example, what's the maximum size of a solar panel that you can put on a moving tractor? How would you go about that? What's what's the limit to that? Well, it would be the structure. What do you think come.

E

Back in the base size.

E

A

Yeah because, like you, you've gone between trees, er and roads right, but why don't you fit a whole football field? Oh I'm, just in a big panel.

D

A

So yeah there's catching on stuff, so for gravity. We would calculate that what's the absolute limit to that by what is the weight of the tractor? If it's a 10,000 pound tractor, how much does in a thin-film solar cell panel way, then you kind of calculate okay? If I have more than this, it will tip over because it's just too heavy, like the button configuration.

E

A

So there's size issues, but what about wind that you're gonna have to consider that to say you get like an updraft. You don't want to sail away with your tractor, so you'd go and calculate when we talked about before the force of wind, 1/2, Rho, V, squared times area of a little formula, they're, basically like V squared. So you can start comparing that force to the actual weight of the tractor. And then you stop. Okay, I'm gonna have 40 mile-per-hour winds and I want my tractor to blow away or slower, like.

A

Let's say we have hurricanes like 60 miles per hour and I don't want my tractor to blow away what is my limit on wind law? I think the wind load would be the number one force, because the panels are pretty.

E

Light they're like a sail.

E

A

That's that's of course, another way to do it. If you don't want to have a mobile power source, yeah yeah by all means, especially if it's automated, then it just goes into its docking station and then you go back but you'd rather perhaps carry because it's a you've gone like way far. You know you don't want to travel too far.

A

E

Different yeah.

A

Different options, but the advantage of it being right on your roof right is you don't have to go doc, you can you can go wherever you go, but.

C

A

A very practical question is, for me: that's I'm, looking at so you got these huge tractors that have like hundred bottom plows or whatever, like cedars, that are the maximum huge Cedars are like 200 feet like crazy. If this doesn't like a so yeah. So if you have mechanical implements like that, why don't you put a solar panel all right on the tractor, just like that's like that big and drag it like right? On top of that cedar like how much power can you get out of that, the numbers are like they get to.

A

You can look at those numbers they get to like a few tens of kilowatts, which is enough to drive the tractor slowly, so you can't have solar tractors and even.

E

If anyone's here, he goes, why don't you just attach the trailer to it and then just love it that bad up with solar panel.

A

Well, exactly that's that's right! Yeah! You can have a whole train.

E

A

About ocean liners that carry the shipping containers I think they can completely be be solar. You can also telescope out and then, when a win or weather gets bad. You can telescope back in so I think this slow solar transportation like this, especially for huge ships that could be completely feasible, but you got to do the math on that and, let's see, do I have a solar ship did I do the math on that.

E

A

Right, yeah, solar.

D

A

I mean it also have more resistance.

E

A

So I do have a solar tractor page on the wiki and they say that the John Deere is maximally a hundred twenty like common implements largest drills, there's six thirty six and forty eight rows like 120 feet. Wide I mean you can draw a huge 120 feet appears to be common for Cedars.

A

So so then you take a look at for a tractor, towable solar panel and we say.

A

Max absolute max say like 60 meters, they have the 120 on your implement, maybe you're even telescoping out because you're doing that, so you have about 15 by 60 meters like just like, literally like over then fifteen by sixty meters on a big implement and at that point, so I kind of took two two limits: 30 meter by 5 meters, solar array. So let me this is. These are real numbers, so 30 meter by 5 meters, so 30 meter is 90 feet which is smaller than the largest implement.

A

So you just say: pasting your implement with solar panels on it. Five meters that's 15 feet, yeah, it's the length of that implement. So it's right up right above the implement you're, getting 22 kilowatts of power at 10% efficiency. You know a lot about 20 kilowatts I mean that's enough to drive that tractor pretty slowly like. If you want to do low, torque high torque low speed that can completely go, you can want to drag thousands of kilos. I mean we did a tractor under one horsepower power keeper using a 5000 pound.

A

Chocolate move very very slowly, but we're the same. Torque, so, okay, 22, isn't that a lot? But now what? If you think about maxing it out say you've got 60 meters, which is like 180 feet. That's larger! So you telescope out a little bit and then, instead of doing a 5 meter, you telescope that out 3 times 3 fold. So it's like you literally expanded like twice as much in each so you got this. You go like this telescope. It out.

A

You know little motors, so we now have 50 meters by 60 meters of solar panel area. So then the 22 kilowatts that we talked about before now becomes 135 kilowatts Electric. Oh, that.

C

A

Plenty of power for a big tractor: that's like a 200 horsepower tractor, though that's all you need. You don't need any more than that for for fast work. So so, even with a slow 22 kilowatts, it would be doable, especially for automated machines that are slow and they just go out there by themselves when it when it's time so I'm just saying it could be done.

A

If you thought about ship liners like like the if it's a tanker like it, one of those big big ships, I mean those things are more than 60 meters and more than 50 meters wide. It's like a several factors over 135 kilowatts, so you got hundreds of kilowatts on a single shipping container ship. Hundreds.

B

Of kilowatts, that's.

E

A

To go I think relatively fast.

E

Like that track your water on it, that's like yeah.

A

It's kind of gets crazy but possible, like if the tankers I mean yeah, like those tankers use up a lot of fuel so for a for an application, that's going like 24/7 it. Typically, a tractor is like a couple of days.

A

In a year a few days a year, you plant you harvest, you, you spray, but ninety or ninety, nine percent of the time, like ninety five percent, perhaps tractors just sitting so putting that big panel is done great, but a shipping container ships I mean they go 24/7 365 days, so I think it would totally make sense to save those I mean what's up, what's the power usage of a container ship. So let's just compare that as a practical experiment here. So what is the power to.

A

Nine megawatt electric motors, nine megawatt.

E

A

Thousand watts: well, we said we already have thirty five. Let's do it quick. How long is a container ship? Let's do this quick and the solar exercise? How.

D

D

A

A

400 meters.

A

Width of a 50 meter, so we got 400. So let's do this math we got 400 times 55 for the size and that's the square meter meter edge and solar panels are at most like 20% efficient for good panels. So you got divide that by 5 for megawatts that's half the power of a standard sense tender ships write written ship right now, so you just telescope that out a little bit, you got the full power of a complete.

E

A

Possibly, oh, no, that seems like you need.

B

I think you need more area I.

A

Think you need more area like the most energy. Intense is solar power I! Don't think that wind turbines, because you have to space them so far apart yeah but maybe I, don't know, haven't taken a look at.

E

A

Well, no interesting, but that's how I mean before we had motors people sailed in ships right and now you can have you have this huge ship with maybe like one big 4 megawatt turbines, I mean they make turbines that are like? What's the max wind turbine largest wind turbine in the world, I think it's like 8 megawatts right now, largest wind turbine.

D

A

Megawatts wow, so the largest largest winter.

D

E

D

A

Baton, the bottom line for solar shipping is that on a solar ship, I'm just typing this on a wiki recording this on a solar ship, you have you generate four megawatts of power from solar on the air in just this area of its deck. That's how you generate four megawatts of solar power from panels at 20% efficiency, so have a have a paddle rack system or just telescopes out a little bit and you've got all the power you need for a supertanker super container ship, which is.

E

A

Same that doesn't get into it. You have to stop at nighttime unless you're saving, unless you're generating extra hydrogen for the night operation, where you're compressing the hydrogen and running on that at night.

A

So that I mean that's pretty interesting, so we just calculated right now and that solar shipping is feasible. So why is nobody doing this.

E

A

Upfront cost will be higher, but it'll pay for itself and I guess. The next relevant question would be how fast doesn't pay for itself. It's probably a year or less I, probably I, probably say it's less. How much fuel does that thing? Here's nine megawatts.

A

Commodity prices, how many prices yeah, but III estimate it's like one year, probably in a year cuz, if you right now, solar panels are 40 cents of watt. Okay, let's do that. So how much? How much is it for megawatt for a.

E

A

Thousand times so, it's four mil a kilowatt yeah, four thousand kilowatts right, so we got four thousand kilowatts and a kilowatt costs about. Well, it's 40 cents, a lot these days for just the panel's 400 400 a kilowatt and you've got 4,000. What's four thousand times four hundred, let's get the number of zeros there. Four thousand.

E

A

400, that's that's 1 million! It's 1 million six hundred dollars. It's a piece.

B

Of cake, that's a fraction small fraction.

A

Of a cost of a tanker, this is completely doomed. That's just that's that 40 cents, a watt, current costs now you're gonna have structures that you have to mount it on. So maybe you double that, but dude how much okay! So the next question is how much fuel does a does a shipping container ship use per year? Oh yes,.

E

A

Well, what did you, google it move it right now, so 1.6 million or the panel's that's peanuts. So question next question is how much fuel that does a container ship use per.

B

A

A

Cargo ship uses 16 tons per hour.

C

A

You are from one ton to 16 tons per hour, so take the worst case: cargo ship. So it's I bet you it's less away than less than the air cargo ship uses for hun order, say 16 times per hour.

A

This is I mean this is amazing. This is where the numerical literacy gets you to all these crazy, crazy things 6000 field per hour, and they also say the cost. It costs about $300 per ton. So.

B

A

E

A

Come out of it, yeah yeah I mean that's, that's commodity price right, so fuel costs. It's probably like crude oil like some some heavy diesel or something fuel cost, is 300 per ton. Okay.

A

So how many hours are there in a year about 8,000 about.

A

8,000 hours so say this thing is running, 24/7 I mean cuz. These things do you know 8,000 hours per year, so you've got 16 times, 300 per ton at the times 8,000. And what does that equal.

A

Sixteen times three hundred times, eight thousand.

C

A

Eight million per year, so you take a and cost us 1.6 million for the panel's, in other words, takes less than a month for the fuel for the solar cells to pay for themselves. There we go so whoever's listening to that, go to business, creating song.

A

B

We take out these.

A

Two powerful the power plant off a chef, yeah yeah, so 38 million dollars per year and fuel.

A

So now, I ask the question again: if that is true, why are there no solar container ships I mean that becomes the.

E

Only interesting question.

E

A

That's about right, so whoever's an entrepreneur, no, the first solar cargo ship, yeah good. Let's.

E

A

Of our friends on that all right.

E

A

Is a worthy endeavor I.

E

Mean these things: okay, the.

A

Thing I heard about cargo ships. They are a major major fuel use on the planet. I did ok.

E

B

A

How much fuel fuel.

A

Do container ships use well, it's huge, but a fraction one massive container ship equals 50 million cars.

E

C

D

See how many car loads of stuff do they transport.

A

Or cargo ship yeah.

D

I mean it sounds like a lot of cars sure, but if they transport a hundred million car loads worth of stuff and pick them up better than cars, yeah.

A

Yeah, they probably do they definitely come out more than cars, but in terms of the pollution, it's the equivalent pollution, carbon carbon dioxide emissions.

A

51 container ship uses create sustain pollution of 1555 zero million cars.

A

So that will call out for solar entrepreneurs to make the first solar-powered cargo ship. We just found out that if you put solar panels on the top of a cargo ship, if four megawatts and if you telescope them out, you get 9 megawatts and that's how much power a cargo ship uses. Now the payback time for that is about three weeks compared to the fuel, because a single cargo ship container ship uses 38 million dollars a year in the fuel. So my question was: why aren't we building cargo ships and industry inertia?

A

But it's a great problem for an open source entrepreneur. So we'll.

C

Finish at that.

A

And continue building so thanks everybody. This has been great. Listen to this, get inspired both the solar cargo ship. That's that's! What the structural calculations session came to we'll finish up that, though, so thanks for listening and we'll we'll see you again in their next steam camp coming right up.

C

A

Might be I think that the proper thing to do would be to the cordless drill challenge, maybe like a car challenge and the solar cargo ship yeah.

E

A

Mean a good order. Three years start.

E

Smaller, you know yeah.

C

E

Really I hate more inside the that further down there, yeah.

C

E

Brendan, like.

A

This the y-axis went out really yeah, so it's not stop moving on a second y-axis, so we have to troubleshoot that I. Don't know what happened. Maybe a wire came out or whatever. Well, you have two printers right now we're running making parts and the third one the y2 went out. So it was printing on one like it's.

E

A

Now I turn it off.

A

One of the three.

E

C

E

Not so the part is so.

C

It's a magistrate law. We got her just cut it.

E

Look like this: it's like new.

A

You know, that's, that's, that's slipping. That means we are jumping teeth, so so we might want to either tighten belt. Another option is that maybe, like the stepper motors are too low, so we need to just crank the.

E

Current up a little bit.

C

A

A loose connection but we'll see: okay, so I'm gonna upload this video and get back down.

D

A

The stepper drivers.

D

Right like if I got the heatsink on I've been just adhesive done. Yeah.

A

I've never had had problems and hundreds of hours so far, but it could be an issue I just haven't run into, but now we could, because now we're going to 24 volts I never had any twelve volts. So maybe that is an issue in which case we would want to add a fan. A cooling fan right over the other.

C

A

Well, it's I haven't really seen I've.

D

Never seen the subscribers okay or I haven't seen anything or eating I'm, just.

A

Too high so far it hasn't worked was the motors that got hot. So we turn him down. You.

D

Can actually touch them right.

A

Before the stuff stepper motors- yes, it.

D

Is possible to diffuse up the Bolton's? We might have gone.

C

A

Well, that was a pretty good discovery about the solar shipping. Yes, you glad I did that, but the world is full of full of examples like this yeah.

E

Things that just haven't been thought through anything always been done. A certain way. Yeah.

A

Well, because for hundreds of years, our hundred years or so of container shipping, solar panels did not exist till few decades ago. So we just haven't caught up.

A

Decades but I mean I wonder if anybody has thought about its solar container ships. I'm sure somebody's talked about this because the numbers add up. Okay,.

E

You, just literally, like you, take just put one level of my layer of ship containers like that.