Hall sensors

The standard vehicle odometer / speedometer gets one click on each wheel revolution, which means it cannot measure very short distances or slow speeds. An eventual project is to build a circuit board that interfaces to the Hall sensors that control the hub motor. The Hall sensors get a square wave with about 17 to 21 periods per revolution, depending on the internal construction of the hub motor. These signals can be outside the 0 - 5V range expected by the Arduino, so use a buffer chip on the Power Supply circuit board. The Hall Sensor has never been implemented. The Hall sensors would be used at low speeds and the standard odometer at higher speeds. The main traction motor converts a 36V or 48V DC power signal to three phases that drive the hub motor. These signals ca reach 25 - 30 Amps. They need to be kept in the proper phase, so the Hall sensors in the motor are low current versions of the three-phase power.