One of the issues I've run into is slippage between motor-mounted drive wheels and the tires on the wheelchair. ABS seems to have a pretty low coefficient of friction. My first attempt to address this was some liquid electrical "tape" I had lying around. I tried both a spray-on version and a brush on version. Both work kinda okay, but they don't look like they'll stand up to long-term stress. They'll just peel off of the ABS over time. For a more permanent fix, I'm thinking a good product to try will be "Shoe Goo." I remember using it as a kid to get more life out of some sneakers, and as I recall it worked pretty well. Since it effectively replaces the sole of a sneaker, it should be both quite tough as well as provide good friction.

I've also found that the screw shield doesn't seem to hold the phono plug wires very well. I'll need to figure out something better. I can easily use a proto shield, I'm just trying to keep the build as simple as possible, especially limiting the soldering to only the bare minimum required for someone to get one of these up and going.

I did get some male and female wire plugs in the mail from China a few days ago, and I've added them so there's now a nice battery disconnect. Still need to add a switch-- I'm thinking a standard household electrical switch will work well, and yet be very inexpensive.

Oh, and I've added a couple of pictures and a short video of the first trial. It's not on the video, but I did try riding in the chair myself, and it had no trouble pushing me around at 160 lbs (73 kg).