1DOF test rig.

[DEADBEEF]

So yeah, this weekend I converted an old rig I had into a rudimentary motion-rig.

Just 1DOF, as I wanted to use an existing rig without having to really make any modifications to it (only had two days so time was limited).

Video:

(please excuse my bro's terrible driving, I should have probably turned some aids on or something).

Here's some pics...

• What I started with.
• Added a wheelchair motor to the back - In use it draws 15 amps @12V, not sure what sort of torque it generates as there's no label on it.
• Two low-friction wheels underneath provide stability.
• My living-room is carpeted, so I needed a frame for it all to ride on.
• Front: Potentiometer above the front bearing (made out of a broken caster wheel).
• An Arduino controls everything. (it'll look better when I have a box to put it in)
• I added a kill switch in case it all goes tits up and I need to turn the motor off sharpish.

Only got done an hour ago, didn't have time to fully calibrate the endpoints properly... It's currently only using ~75% of it's max deflection (max is 30 degrees both ways), and it's a bit jerky when making small movements. All this should be easily fixable though.

I had to write my own Arduino controller for the Monster Moto board. I tried this one but it was pretty basic and wasn't really suitable for this rig which has a lot on inertia / momentum and a relatively short potentiometer throw (60 degrees total, 30 on either side).
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It was pretty cheap to make though:

• The original rig was entirely made out of reclaimed (free) timber, as was the base for it to roll around on.
• The seat was off an old truck I have rotting in a field.
• Wheelchair motor with 25:1 gearbox & drive wheel was £25 - EBay.
• Nylon trolley wheels were £10 - EBay.
• The Arduino is a clone, so was pretty cheap at £14 - EBay.
• The Monstor Moto was a knockoff and cost £15 - Deal Extreme (I had to order this quite a bit in advance, postage took ages).
• Assorted bits: potentiometer, tape, solder, etc. was probably an extra tenner.

Total: ~£70 (including all postage)

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So yeah, that's "Skid Mk1".
For "Skid Mk2" I'll probably add some windscreen wiper motors to tilt the seat about and simulate G-forces.

[gaevulk]

nice job!!!

[vicpopo]

Hi ,

Many good ideas !! Great job !

[prodigy]

It looks good and not hard to do it.

But how does it feel in the game? From the video it looks like it is giving you feeling that you are loosing your rear end of the car everytime you are turning left or right and that can't be right, you will probably need to do some calibration. YokoYoko could probably hrlp you with traction loss setup.

But I bet it is fun now, it's better than nothing right?

[DEADBEEF]

Yeah, currently it just moves with lateral acceleration which isn't particularly realistic.
Ideally I'd want to set it up to represent the difference between the direction the car is pointing and the direction the car is moving (up to 30 degrees at least).

That should give an accurate handle on how much the rear end is stepping out. Which I'm hoping will be pretty fun, in rally games especially.

[aboodix5]

good job!


can upload pic to see how you build it ?