Combined time-of-flight and Doppler ultrasonic tracking system for better performance in robot tracking

An integrated ultrasonic robot tracking system that combines both a time-of-flight (TOF) and a Doppler tracking system is introduced. As TOF and Doppler tracking systems both have advantages and limitations, better accuracy and resolution can be achieved in three-dimensional dynamic robot tracking by combining the two systems. In the paper, the working principles, structure and experimental results for the TOF, Doppler and the combined tracking system are described in detail