Line-Following Robot
UC San Diego ECE 5 Course: Intro to ECE
Description —
Control theory is using systems to control the action of another system in the most efficient way, without undershooting or overshooting and maintaining a controlled path or result.
The objective of this lab is to show complete knowledge about major concepts we have been taught in this class: wiring circuits, creating 3D printed parts, controlling using sensors and actuators, soldering components and interacting different systems. All these parts relate in order to achieve the goal of creating a line-following robot.
Reflection —
The most valuable experience to us was gluing down all the components of the robot without testing it to make sure the parts work, running the code to realize that one LED and one of the motors was not working properly, discovering that some weakly soldered parts broke off, and noticing that the photoresistors started falling out of the breadboard; and then deciding to meet up at 8pm on Tuesday Dec 4 and fixing everything till around 2am. When Roger (the robot) finally worked, we all went home tired but satisfied :) A true experience.
Acknowledgements —
Thank you to my amazing team members: Sarp User, Nikki Grewal, and Scott He. Also, thanks to Karcher Morris for teaching this fun and truly memorable course!
All four of the potentiometers decreased in value when turned clockwise. The potentiometers also reached 0 and 100 a little before the know was turned all the way. You need to calibrate the photoresistor values to create a uniform measurement. Factors like light and sensor position can alter the readings, so it is important to keep a uniform measurement for accuracy. Calibration helps prevent inconsistencies with light and other factors. It also helps the robot to be able to detect and follow a black line. The predicted problem with the photoresistor is that it may not accurately follow a black line on a white surface if there are other detectable black marks on the surface.
The photoresistor output for a white surface: 331 175 259 232 179 273 458
The photoresistor output for a black surface: 682 811 893 719 836 859
I designed the CAD model. The chassis was modified by adding a second layer, supported by two cylinders. We will print the two layers separately to minimize the supports generated by the 3D printer. On the top layer, there are compartments which hold the potentiometer breadboard (which has our names on it), the Arduino and the 9V battery holder. The bottom layer modification is the breadboard for the photoresistors at the front and the AA battery case at the back.
