Power Wheels Dissection and Quadrisection

As mentioned before, the Mercedes as it came out of the toy factory is much too small for a grown human to fit inside and is well within the size restrictions for PRS. As such, I had to do a bit of custom modification to the body to make it big enough for a full grown Eric which required some minor disassembly as well as some major dremel-ing.

 

I initially cut out the base of the body to see if I could fit inside without the seat and floor, to no avail, so it turned into a full on quartering. I stitched the thing back together with some good old cardboard and duck tape so its width fits nicely around the salvaged transaxle and the wheelbase has the same proportionality to the width as a real Mercedes Benz 300SL (about 1.34:1). The next step with the “biggening” of the body is to get some bondo or modeling clay and fill out the holes until it’s once again nice and smooth. The end result will be a fiberglass mold from which I can cast infinite fiberglass bodies to paint and interchange and replace in case of damage.

An issue with the wheels I ordered is that they are all free-spinning with bearings set into the rims. This was, of course, a problem when it comes to driving them with a motor and the solution was going to be welding two of them straight to the rear axle. Luckily, the wheels of the salvaged scooter are the same size as those that I purchased online so the split rims already screwed into the transaxle can be easily re-fitted with the tires and tubes from the aforementioned internet wheels.

Doing this took way more effort than I had hoped (taking tires off of solid rims is a nightmare), but the transplant was a success and now I have a nifty assembly for the rear axle and wheels.

A new thing that I’m finally getting around to working on is the power supply for car. It should take in the 36V from the battery and distribute it as 36V, 12V, and 5V for the drive motor, autonomous control motors, and various logic components respectively. It’s secondary function is to monitor the voltage and amperage coming out of each power rail and shutdown or limit each subsystem in the case of overvoltage or overcurrent. I drew up a really rough design that gives a pretty basic idea of how it will look, it will get refined over time as I nail down each subsystem controlling and monitoring the car.