CE432 Robotics II   Fall 2021
Final Project: Balancing Car
Humberto Arredondo
harredondoperez@fortlewis.com


1.- Introduction

In this tutorial the students were assigned to create a self-balancing robot car that uses two wheels. These two wheels needed to be rotate by two step motors and controlled by an Arduino Uno module.


The equipment and materials used for this tutorial was:

2.- Methods and Results


The chassis of the car and assembly was achieved by cutting acrylic boards and put them together using rods and nuts (Figure 1). 3D parts were designed and printed to hold the breadboard, batteries, and the step motors in place. Once the chassis was completed, the Arduino, two A4988 modules, and the MPU6050 were added (Figure 2).




Figure 1. Complete chassis and stepper motors assembly.


Figure 2. Complete self-balancing car wired up.

The A4988  was calibrated first (the value was -1911). In Figure 3, the first column shows the angle and the second column represent the error.



Figure 3. Serial monitor showing the calibration results of the A4988.

Two PCB for the car were designed in Eagle. The layout and PCB for the car are shown in Figure 4. The layout and the PCB for the remote control are shown on Figure 5.



Figure 4. The PCB design for the Balancing car designed by Mychael Garcia (team partner).




 Figure 5. The PCB designed for the remote control.

The final progress in this project is shown in Figure 6. The 3D parts were printed in green for holding the breadboard, in red to hold the battery, and yellow to hold the motors. In this occasion, the balancing car project was not successful, they were many issues on the code. I was not able to make the balancing car to stay balance myself. In the other hand, my team partner Mychael Garcia was successful on his. Figure 7 shows a video of his car self-balancing.



Figure 6. Balancing car completed using the breadboard and showing the remote control.



Figure 7. Balancing car in action.



Discussion:
This project required a big dedication in time, the skill for programming were high. A full overall of skills were needed to successfully complete this task. Skills such as coding, designing a PCB in Eagle, knowing how to use datasheets for the modules, and the ability of pairing all together. Unfurtunately, my car was not working properly, some issues were: the motors kept on not going fast enough, motors will keep on stop spinning and they sounded stall just to mention some. For the future I will recommend to wait on the design of the PCBs until all the issues have been taking care of and the actual car is working properly.
Overall a great wrap up project where you put all knowledge to the test.