In my Junior year at Olin college, I worked with Mark Muraoka, a friend of many years, to convert an electric remote controlled vehicle to a hybrid. The goal of the hybrid was to simultaneously increase performance and range, while using a minimally affecting effeciency. We used two brushed DC motors with separate controllers and a 2.5cc nitro engine controlled with a servo to drive. Each power source was controlled with an Arduino taking input from the remote control reciever. The end result could easily reach 40mph and would only burn it's onboard fuel when the nitro engine was most efficient.

This is the chassis we started with, a standard Traxxas E-Maxx with dual brushed motors. The stock truck uses a single controller and the same pinion for each motor, with both motors driving the same spur gear to the transmission. Our system adds a second controller for independent control, and we replaced one of the pinions with a smaller gear. This allows us to utilize the most efficient part of the motor power curve for each speed in the vehicle's acceleration curve. To be continued...