World's First SCREW-BIKE

Remember when I made a

bike

with an omnidirectional wheel on the front wheel that rocked like a Segway sideways but you could still ride it like a normal

bike

because the front wheel had a lot of skateboard wheels around it so it would slide? A while later, I went ahead and tried to make a two-wheeled Omni bike instead of building the electronics myself, although I did remove the guts of a hoverboard, including the motors. I tried to get the Velocity to combine the original wheels with the new larger wheels using belt drives which worked well, but the only way to drive it was with EDFs blowing it, which wasn't very successful.

As soon as I put that version together, I realized that it would have been better to have made mechanical wheels that had the little tilting wheels around them typically used on the four corners of a robot so it can move in any direction, but I wanted to put them all in. in a line so the bike still balances sideways but can bolt itself together. In fact, I found a YouTube video by Matthew Watson where this method was used to drive a small robot. I think it was a PhD project and it works very well, in fact I can't find any other version of this type of locomotion and I certainly can't find any. versions that are B enough to ride so yes you can buy mechanical wheels on the market but the biggest ones I can find are 254mm diameter which is very small and they are very expensive like 7800 and I already made two Omni wheels huge, so I guess I'll have to make four huge mechanical wheels.

Yes, of course, I will 3D print most of the parts. I'm building an enlarged version of my mechanical wheels from the smaller robot I showed earlier. Each wheel is will be around 360mm in diameter and will have 12 small wheels around its circumference, so I need 48 small wheels in total, just a quick addition from my 3D printing sponsor. Thanks to lsot for supporting my channel with 3D printers. I'm printing. the tires in 95 to TPU from 3D Fuel and the wheel hubs in 3D fuel bow. Plus, you can now get 10% off 3D Fuel products with my special code and I'll also receive a small commission.

There are also 96 wedges to place. at each end of the axles to keep the wheels tilted, but I'll save you the images of how to print each of them. I printed the TPU wheels with a 1.2mm nozzle on LSB printers and they are incredibly strong and that means It's very very difficult to push the hubs in so time to use the hydraulic press thanks to Simply Bearings for the bearings From this project. I have 96 skate size bearings for each end of the 48 wheels and of course some larger bearings for the actual big wheels, so we need to make some wheel hubs to mount all of this, so as usual, I'm going to use some plywood CN seed so we have some holes here that are being drilled in a huge circle and that's what We can put all those shims in and we also need a few more holes to line up all the pieces with a cube in the middle and making sure the wheels are in the right place so we cut some circles and I also have an HTD eight profile pulley and one of them will drive each wheel so I painted them all black with some spray paint for cars and you'll notice that there are some very shiny sections in there and it's actually duct tape, which I've put where the four holes are to mount each of the shims and that's so I can stick them on and there's something to stick to besides paint so I have a solvent based adhesive to stick each of them on and I'm also going to

screw

them together so basically they never come off because I'm going to be sitting on top of this and that leaves us with a round piece of wood with 12 shims glued and

screw

ed on the other side.

I have the ht8 pulley and I also made a thin plywood retainer so the belt doesn't fall off and will be used to drive the wheel. This bushing fits into a 3D printed part that is printed with a diameter of 1.2mm. nozzle so it's a really sturdy 3D printed cube and I have bolts that go all the way through and they fit pretty well we'll just tap them all in and eventually that will hold the other side in place as well for now. We need to fit all the wheels, so we have these pieces of 8mm stainless steel rod that go into those shims around to get the spacing right.

I have a couple of nylon washers and then we can put them all on. the small wheels with their bearings around them, followed by two more nylon washers on top of each one, leaving them perfectly spaced so they don't move. We have another set of 12 wedges that go all the way around. At that point you can probably guess that with those bolts sticking out, we're going to glue another plywood cube on top and then we're going to glue and screw all those shims on the other side and that makes the wheel complete. I twisted the bolts around them so the piece sticks out with the nuts in the nice gap I left.

We need to put a bearing on each end of the wheel, but the hub was printed with a huge nozzle. I printed another part with a finer nozzle, a half mm nozzle, which makes tolerance much easier and we can reprint that part if needed without having to reprint the entire hub so we can fit the bearings nice and tight , and those have 20 mm internal diameter. I've made four of them in total and you'll notice that I remember to make opposite pairs so that the wheels go in opposite directions so they can bolt together to travel in the same direction;

Otherwise, the balance will be difficult. It's really difficult so what we have to do now is put them all on a chassis and put some motors on their chassis so that's my main chassis and these four pieces stick out while I'm holding the four motors so actually the wheels They go under this and this. The weird thing about the saddle here is where we're going to put the footrests so we have to put the wheels on this piece of shiny steel bar hanging underneath and we have to make it all adjustable so I have a 20mm rose. 20mm threaded joints to match the uprights and 20mm holes to match my axle and these will all go through the chassis crossbar and bolt together so we can adjust the height of them and we can get that axle. through them all perfectly, threading the eye of the needle every time and then we can align and space all the wheels correctly, so now it's time to put the wheels on, which is a bit of a test because the shiny steel bars 20mm is enough with a tight tolerance for the bearings, I can do it, but it will take me quite a while to push it and push all the wheels without forgetting of course to put the drive belts on

first

, otherwise I will never be able to put them on.

There is a colored clamp on the end and there will be more along the axle to hold the axle against the rose joints along the bike so now all my wheels are perfectly aligned and they all work fine and I have placed all nuts on that stud so we have everything at the right height so the belts can mesh with the motors, so we need some spacers. Right now, those can slide up and down, but we need to line them up. Perfectly with the motors, you may have noticed that I actually put the wheels in the wrong order, so I had to take them all off and do it again, but even with no gaps there, if I slide this up and down along the length, we can see those wheels turning against. each other as my little animation, so I'm very happy with how the lineup has gone so far.

It's time for some engines. Remember the video I made with Colin Furs where I built a version of his rhino tank and he helped me test it? Yes, that's what we were made for, going through the mud. I'm using the same motors and drivers from that project. These are 100KV brushless motors with an O Drive S1 at the back, there is a magnet on the motor and an encoder on the board so that the position and speed or torque can be controlled precisely. This is a really neat unit and I built a two stage belt reducer for the tank, this time we are going to need a little more speed so I have doubled the size of the output pulley that drives the wheels, motor and reduced set were placed on risers I made on top of the main chassis cross bar and straps, with blocks under each set, I made a steel quick stand for it, so I can tilt it and work upright and I have also fitted the top part of the chassis that will hold the handlebars, saddle and electronics and that is a bolt on piece so I can remove it to get to those motor assemblies if I needed them, on the last Domy bike I made a headset assembly which basically tilted sideways and also rotated and that's what used to control all the axes, however there was nothing solid to hold on to so it was a small mistake in the end which caused me to crash so that this time I made the handlebars that are completely fixed and do not rotate at all.

I found this saddle on Amazon that fits perfectly, so I'm very happy I did. The way it looks is pretty retro, right, it will be one of the best things I've ever done if it works, but we need to put in some electronics and start the motors and see what happens, but before we continue putting that together. time for a quick addition from the video sponsor which is ODU Odo is an all-in-one management tool that provides business owners with a wide range of web-based applications to simplify the management of their businesses. The

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AI generated text is available in ODU to fill out any section I quickly put together a website on. this project and you can try ODU. Now, visiting the link in the video description, let's continue with the bicycle project with mechanical screw wheel, omnidirectional wheel and linear drive, so I made an electronic box and there we have a Tec 4.1 we have a b86 spark fun IMU and we have the canbus transceiver to control all O units on top. I have a battery monitor and an LED strip that is currently displaying the IMU data. I also have several knobs on there, so we have a trim control which is for the inertial measurement unit data and I also have a switch to initialize the O units and I have a volume control which we'll talk about later.

I have connectors that come out including the USB canbas, it feeds the 48 volt power so I can monitor the battery and a connector to go to the handlebars for all the switches. I have made a battery case that holds four lipo 6s and let's go. to put them in series and then pair them in parallel so we basically get almost 50 volts out of that there is a 200 amp contactor on the top and that will connect to the electronic stop on the handlebar so I can cut the power off if I need the Electronic components are placed right in front of the saddle so they are nice and accessible to control.

Yes, it is a USB charger that powers them nicely and professionally. The gray wire is a can bus that daisy chain between all the O. units to control them and all those batteries are in the back and yes I have a cover there to cover the dodgy bolts that has 50 volts. I've built quite a few balance robots in the past. There is a playlist on my channel. For balancing projects that use various means to stabilize unstable things, the main thing that makes balancing robots work is a p ID controller that takes the angle data from the inertial measurement unit and controls the wheel speeds appropriately. .

The term proportional simply means that the wheels go faster. if the angle is larger but this is not enough for the device to balance correctly, the most important part is the integrator, the output of the integrator is the area below the graph, so if the angle is constant as the time, the output increases asthat time passes. This area increases over time if the angle increases then the output increases exponentially so the integrator accelerates the speed of the wheel to catch the robot as it falls which happens constantly. The derivative term is the tangent to the curve of the angle data, so this makes a short, sharp velocity move to dampen any excess.

It is necessary to adjust the three terms for the mass and power of the robot, which is a bit like focusing a camera with three lenses, but normally the largest value is the integral term and the smallest is the derivative, however, if the device is left at an angle without the motors on, then the integral term tends to accumulate a large value and when it finally comes time to balance it, it causes the robot to suddenly kick until it is stable. This was a problem with the first Omni. bike so this time I have a control so I can slowly increase the output which makes me less likely to break my ankles when I turn it on, the button initializes the O units and now I can slowly increase the output of the P Controller ID To get things balanced without it moving as much, it was pretty easy to adjust, but larger, heavier robots tend to move less because they have more inertia, so it's a lot easier.

It's easier to adjust the P ID controller so that they balance correctly. Let's ride it. I've actually adjusted it so that there is one person instead of none, so it should work pretty well and I'm really happy with how good it is. works almost as good as a Segway oh yeah this is really good, it's much better than the last one made with a hacked hoverboard, mainly because I couldn't adjust those P parameters on the hoverboard again, so even a little bit of mass. Shifting makes this thing move, which is good, it's almost as good as a Segway.

I definitely have enough speed to keep my balance there, but what we need to do now is try to screw it up by moving those wheels in opposite directions and see if that works. So this is going to be cool, so I have a twist grip on the right side that moves in one direction and I also have a toggle switch so I can drive forward or reverse and all that. is to make the wheels turn in opposite directions to turn and transpose that value over the equilibrium value, okay, let's try and move on oh, it works oh yes, this is brilliant, this is brilliant, oh yes, I think we might be slipping slightly on The floor is smooth but feels amazing.

The rotation is controlled by another rotating grip. Ideally I want a twist grip that rotates back and forth so I can turn left and right, but I couldn't find one that does that so I just have another direction switch. and we'll see how it goes. I thought about having foot pedal switches for the steering, but I thought this would probably fall off at some point and bend or break if attached to the foot pegs, so I decided. The handlebar controls were better now of course, the wheels are at different distances from the center and that means they need to spin at different speeds so we can turn around the center point.

Basically one circle is bigger than the other so the outside wheels have to go faster, we need to keep that in mind, let's see where the rotation takes us oh oh oh oh, I think I want my mass in the middle, ya that that's where the rotation point is, yes, that seems to be it, seems to be very good, who? Wow, who feels amazing, we need a bigger space to try it than this one though because there's really no room in my kitchen. Uh oh, this is amazing, it's one of the best things I've ever built.

Oh, and yes, the lighthouse. works for those of you celebrating this entire project will be open source like all my projects are so all CAD code will be published on GitHub if you want to create your own or use some aspect of it for your own projects if want to support me for a YouTube channel membership or patreon, then YouTube channel sponsors and members get access to all videos up to a week in advance and previews and images of what's to come, plus the benefits of Discord and talking from Open. Source: I'll be at open source 2024, which is June 15-16 in San Francisco, but apparently it's a different type of source or something.

There will be 150 YouTube content creators and 500 community showcases, but they are looking. for more exhibits and you can apply now on the open source website open source.com and if you are successful and your exhibit is accepted you will get in for free and have access to the exclusive opening party on Friday night that I will be at. along with all the other YouTubers, hopefully, so check it out now.