Ultrasonic Rangefinder Forward till Near - ROBOTC.net

Sensing
Ultrasonic Rangefinder Forward till Near (cont.)
The Ultrasonic Rangefinder offers exactly this capability. Using the same physical principle
as a bat or submarine’s sonar, the Ultrasonic Rangefinder measures distances using
sound. It sends out a pulse of sound, then waits to hear the sound’s echo off of a solid
object in the environment. By measuring how long it takes for the sound to bounce back,
the sensor can calculate the distance that the sound must have traveled, and hence, how
far away the object was that reflected it back.
The Ultrasonic Rangefinder will work in a very similar way to the Encoder program you
wrote in the previous section, but instead of measuring the distance that the wheel has
turned, it will use the Ultrasonic Rangefinder to measure the distance to the nearest object
in front of the arm.
1. Add an Ultrasonic Rangefinder to the front of the robot’s arm. The design shown below
will be used as the reference for the remainder of the unit. If you choose to use a
design that differs significantly from this one, you may need to adjust accordingly.
© Carnegie Mellon Robotics Academy / For use with VEX ® Robotics Systems
1a. Add the sensor
Attach the Ultrasonic
Rangefinder to the front of
the Squarebot 3.0 arm.
ROBOTC
Ultrasonic Rangefinder • 2