Line Following/Autonomously Driving Robot

In the later ECET classes at DeVry a challenge project was given to create a line following robot from absolute scratch. The only start point that we could use was to buy/find a RC car to use as a platform and the motors, but that was it. I loved this project as it gave a tremendous amount of knowledge on how to start a project from a concept to a final working electronic device. In this project we used a large scale Hummer H2 RC car that I had as a kid. We were also given an extra challenge to develop our own motor controllers rather than use after market ones. In the video you can see a spare motor from our lab being driven by an H-Bridge I made being controlled by the Freescale 9S12g128 MCU. Once we got the motors working for moving and steering the line following detection circuit had to be made. This was a big challenge as we did not have many inputs for data on the MCU. We had to make a three state detection system to tell the robot where the line was. This was done with three biased comparators and photoresistors supported by the reflection of IR LEDs hitting the ground. Depending upon the line a high or low would be sent to the MCU to be processed for deciding what to do. In the end the project was a huge success because the robot was able to start and stop following the line but was also able to re-find the line when it hit a sharp turn.

After the presentation we were challenged to make a different system to help allow the car find its way around. We developed a whisker system that allowed copper wires to fold and send feedback the car might hit something which allowed to car to avoid the obstacle.