Robot App Store

Robot App™ Description

This app locates a wall and then drive alongside the wall in parallel. The idea is that the robot uses the radar to compute the angle to the wall, and then adjusts its steering to set the wheels pointing parallel to the wall. Of course the robot has to take periodic measurements to ensure that it is not deviating from the chosen course!

Developer: Mark C


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Installation Instructions

Delivered as:

Code

Robot-C code - Click the Download button above to see it.

Robot App Requirements

Software

Hardware:

Other requirements:

Usage Instructions

The basic idea is to take three radar measurements facing the wall and from the distances returned determine whether the robot is parallel to the wall, or turned to the left or right relative to the wall face. For this we’ll use some trigonometry to solve for the angle between the robot and the wall.
First off, the angle we are looking for is given as the letter A in the figure below. If the robot is facing the wall straight on then A = 90 degrees.

To solve for A I used the Law of Cosines and the Law of Sines using the measurements obtained from the DISt-Nx sensor. To begin, we measure the distances from the robot face to the wall.