Over the last Labor Day weekend, I spent all my time making the car a bit more polished and safe for driving. This meant moving the batteries and contactor assembly to the trunk, attaching the charger, and securing items in the engine bay. That was about as minimal as it can be while still feeling safe about a more rigorous drive. And it was…. interesting.
The drive actually went very smooth, no hiccups at all. The car maxed out at about 30 mph in 5th gear, which is perfect for the 72v system. I was impressed to hear that the motor assembly is actually well aligned. I noticed no real vibrations or loud noises from the engine setup. And it was able to drive up around a 6% grade with no hesitation.
Now there’s still some items I need to take care of. The brakes on the car are extremely rough after sitting for 2 years and the components enduring 202k+ miles. The throttle needs a much more delicate curve, it currently lurches forward hard with the least throttle input possible. The controller needs to be attached somewhere and a fan would be a good addition; the heat sink was quite warm after the ~5 minutes of driving.
So the next safety related steps are to build a metal structure to brace all the batteries in the rear and adding cooling to the motor controller. The batteries need bracing so they don’t tug on the cabling, and also to be protected in a collision. Adding some fans would be a good safety precaution as well. The best way to integrate them will be to have the Arduino Dashboard to trigger them, with a manual shutoff via the switch panel. The plan for the custom dashboard is to be a hub of important statistics and vitals; having the information regarding temperatures would be useful. I also want to log the throttle pedal, amp draw, voltages, and stats like vehicle speed. That last metric is if I can get CAN communication working. I don’t feel fully safe putting an Arduino in control of throttle, but logging the information seems harmless. And the battery cables running under the car need some grommets and retaining straps to keep them safe.