An electric motor control unit for controlling the operation of an electric motor. The unit comprises: an electric motor controller comprising a processor having at least one input and at least one output, wherein an output of the processor is coupled to a power provider for controlling power to an electric motor; a tilt accelerometer system comprising a tilt accelerometer for determining a measure of the tilt of the electric motor unit relative to a reference orientation, wherein the tilt accelerometer system comprises an output for providing a signal based on the determined measure of the tilt; wherein the output of the tilt accelerometer system is coupled to an input of the processor of the electric motor controller; wherein the power provider comprises a power output for controlling the operation of an electric motor based on the output of the tilt accelerometer system.