With hub motors
1 Like
Spherical wheels with hub motors for stability
So how does the throttle work??
2 Likes
This is such an awesome build. Must be nice riding in 20s
3 Likes
Respect! That’s some quality work all around. …and you made something that’s rideable. Very impressive.
I love single track vehicles. The feeling you get in the twisties is magic.
Great to see a fresh take.
3 Likes
Looks like a linear actuator attached to the knee (shin) pad on his back leg so he can lean forward and back to control the speed.
1 Like
This thing is awesome
If there is one thing I want to see is a video of you getting on it and starting, how you handle that with the throttle being attached to your leg?
4 Likes
The telescoping section doesn’t do anything other than let the linkage comply with my motion. The only thing it picks up for throttle control is rotation.
The black component just to the right of the red fiberglass wall is an analog twist throttle. The notch in the red 3D print captures its little control lever. Also, imagine that I’m making motorcycle vroom vroom noises as I twist my wrist, because the throttle on my board operates the same way.
It doesn’t look like much, but that took me about 2 weeks to get down smoothly lol. The sequence of events is that I shift my leg around to feel for the edge of the throttle, give it a little push with my foot on the ground while I give it a little bit of throttle as well, and then hop into place. Once I get my front foot situated, I’ll give it the beans.
21 Likes
How well will that tire rim hold up against lateral deformation? Don’t think it’s a meaningful issue, but curious.
4 Likes
2 Likes
Bike tires can roll off the rim if you run them at low pressures and really scrub them sideways, but neither of those things is the case for me. I run at 90psi, and I can’t exactly make this thing do a Scandinavian flick
1 Like
Outrageous. I fuckin love it man- great build thread, keep it coming bb
6 Likes
Abso-fucking-lutely awesome!! I just love that you went full “I’m making my own hinges”.
How did you hook up the mechanical brakes at the end of the travel? If they ever engage, don’t they lock up the front wheel and send you flying/fully steer?
1 Like
Yep, I suspected it might be necessary to use the same Rulon J bushings that Sbeepdord™ does, so no off the shelf metallic hinges for me. I also wanted to make them integral with the linkages for structural reasons.
It was necessary btw, greased bronze bushings were terrible to ride on. The startup friction kept the steering geometry from doing its job of stabilizing the lean, but Rulon J is fukken butter.
It’s no mystery, i adjusted the cable length so the pads hit the rotor after the ESC hits full regen. Braking force depends on how hard you push on the LegStick™, and there’s no steering force since the caliper is mounted to the same plate as the axle.
2 Likes
I see your title of “fucking madman” is well earned… awesome project!
2 Likes
Oof. So I was riding around yesterday, a bit harder than usual but nothing insane, and at one point after a hill climb I felt a lot of drag suddenly kick in, as if I had lost a quarter or a third of the throttle. A few seconds after, I saw the magic smoke coming out of the speed controller and pulled over, and it was clear the brakes had gotten a little weak.
The motor is now cogging as if two of the phases are shorted together, even when disconnected from the speed controller (which explains the drag). I’m reading about 18 ohms between each set of phases, and about five thousand ohms between each phase and the motor mounting plate (not sure if that was there before). No shorts between phases of the speed controller and no visible burning on it either, but I can’t get it unglued from the heat sink without breaking it to see the reverse side of the power stage.
So I’m guessing a busted motor killed the ESC, right? Although I suppose it could still be the other way around.
3 Likes
What is the resistance between all the phases on the controller? Should be about 300kohms on that one. If one is off might be shorted/blown open mosfets.
4 Likes
Yep, reading about 290k for all 3 pairs.
The part I’m most confused about is why the motor feels like only two phases are shorted instead of all three, but all of the phase pairs are reading the same. Maybe I should take the connectors off and short them manually to check.
2 Likes