2DoF 24V Wheelchair Build

Just got around to look at your page. Very nice job indeed! And in such a quick time frame (relative to me that is lol).

Have been finishing up a few details and becoming more familiar with Simtools.

First two games running are No Fear 2 and Epic Roller Coasters and my 8 year old son absolutely loves the sim. I'm just jealous because I can't take 5 minutes of VR roller coaster while he can ride for hours on end.

Got the plugins for Assetto Corsa along with Competizione installed for tuning Simtools. I don't do any set up in VR, drive and look at the monitor and then make adjustments.

Last night was the first night of driving AC Comp. in VR and all I can say is f**king WOW!!!

I have got to download Content Manager and get Assetto Corsa in VR now!

If anyone ever looks at this thread, don't build a 2DoF, just go right to the 3DoF with traction loss. You won't regret it.

A bass shaker is in the near future but the dual sound cards and Windows 11 has me a tad apprehensive.

Just about wrapped up.

Flying is going to have to wait a little, learning how to drive has me hooked atm in ACC.

And it can all be broken down and moved to another location by a single person. Unbolt into three separate sections (26 bolts), remove motors from mounting brackets and all cabling can be unplugged.

I didn't want a boat anchor in the basement

Was a little worried that the 20 amp 500 watts power supplies in combination with the rig's weight if it could handle a bigger guy.

This was the 200 pounder and it passed the test.

https://youtube.com/shorts/H2vD-NK6Tog?si=_AYyB7IVLs7D-W-v

In the video above you could see the right side motor struggling and drooping.

When assembling the control box I knew putting the IBT-2's in line relative to the airflow direction was not a good idea.

The IBT-2 for motor 1 was closest to the fan so all the hot air from it blew onto the IBT-2 for motor 2. During long driving sessions, the IBT-2 for motor 2 would get too warm and would trip or not be able to hold itself in a null position for more than a minute or two without any weight in the seat and then thermally trip.

Had read a lot of build threads but underestimated the amount of heat the IBT-2's put off. And once they get too hot, they thermally trip to protect themselves and shut down. The heat sinks get very hot under normal use so good cooling is absolutely required to get consistent power delivery.

When assembling the control box, I knew the segmented front panel was restricting airflow and should have cut holes to let the case breathe freely.

Did that with a hole saw and can now turn down the fan speed in the control box case too, less fan noise.

Also knew that the power supplies should have been mounted on their sides to conserve space.


And finally looked at the diagram of the bridge rectifier to properly wire it up for DC use. In the attached pics, the one with the motors attached to the rectifiers is the correct wiring.

The way it's wired in the picture when changing the layout will never work in a DC application. For this use case, you must attach the +/- from the IBT-2 to the DC sides of the bridge rectifier. The motor lead is then connected to the AC side of the rectifier.


Rig performance is now greatly improved.

For best operation keep the IBT-2's as cool as possible.

At 18VDC, the rig can jump around if you want to thrash yourself that hard and it's a heavy rig. Currently running at 17VDC with plenty of torque.

Literally, first few nights in the rig and would wake up the next morning with a sore lower back. No back issues at 58 years old either and a bit of a bummer to dial the action back somewhat.