An encoder fault tolerant FPGA based robot control using bluetooth of a smart phone

An FPGA based Bluetooth controlled robot with encoder fault tolerant algorithm is presented. The smart phone is used to obtain user intentions, such as turning, speeding or braking and this data is sent to a robot using Bluetooth. The motor control algorithms and robot communication interfaces are implemented on FPGA for parallel processing. The robot is capable of changing its position with the help of two independent PI closed loop speed controlled DC motors. The motor speed is determined by the accelerometer of the sensor data of a smart phone. The FPGA receives speed information and generates appropriate PWM signals. Motor rpm is calculated via rotary encoder. In case of an encoder failure, an on-board gyroscope helps maintaining normal operation. An Android based smart phone application has been developed. MATLAB is used for simulating an encoder failure and observation of results. The motor control algorithm has been implemented using Verilog and tested on the field.