One of the important capabilities of a mobile robot is navigation. An ideal navigation means a robot can plan its path from its current position to the destination and can move without any obstacles. We use ultrasonic distance sensors in this robot for detecting near objects that can't be detected using the Kinect sensor. A combination of Kinect and ultrasonic sound sensors provides ideal collision avoidance on this robot.

Ultrasonic distance sensors work in the following manner. The transmitter will send an ultrasonic sound that is not audible to human ears. After sending an ultrasonic wave, it will wait for an echo of the transmitted wave. If there is no echo, it means there are no obstacles in front of the robot. If the receiving sensor receives any echo, a pulse will be generated on the receiver, and it can calculate the total...