Nowadays the steering of most cars is done by electric power assisted steering systems. The software of the electronic control unit needs information about the position of the steering wheel, which information is also used by other electric systems of the car. The purpose of the thesis is to explain how electric power assisted steering works, and give a solution on calculating the angle of the steering wheel.
As the preparation of the development I studied the available sensors and microcontrollers for this task, then I chose the applicable elements after some research and measurements were made. In the thesis the operation of the sensor, the used functions of the microcontroller and the switch circuit is thoroughly explained. After that the software running on the microcontroller is presented, which is able to calculate the position of the steering wheel using the output signals of the sensor. During the development several simulations and measurements were made, and with them the proper functioning of the rotor turn counter can be shown.
The low power condition played an important role while developing the rotor turn counter, which can be solved by placing the microcontroller in sleep mode for a specific amount of time, then awakening it for the proper amount of time as well.