Ultrasonic Sensors
Before moving on to the algorithm for obstacle detection and
collision avoidance, the sensors used for research need to be
discussed. Ultrasonic sensors (model: HC-SR04) [8], shown in
Figure 3 have been used for avoiding obstacles here. These are
low cost ultrasonic sensors containing a receiver and a
transmitter of ultrasonic waves. The sensors give a 4-pin
interface for connecting with a microcontroller.
Pin 1 is for providing the biasing voltage to the sensor
(Vcc).
Pin 2 is for Ground connection.
Pin 3 is the “trigger” pin.
Pin 4 is the “echo” pin.