Project of a Self-Balancing Robot Using a PIC Microcontroller

Abstract

The project developed as part of the subjects Instrumentation, Microcontrollers, and Control Systems, studied in the fourth year of the Control and Automation Engineering course, aims to create a robot that simulates the behavior of an inverted pendulum. This implies designing a robot capable of autonomously balancing on two wheels, interpreting data provided by sensors, and taking actions based on that data. This project provides an opportunity for the practical application of the concepts covered in these subjects, emphasizing the integration of knowledge in a single project. An inverted pendulum is an unstable system since its center of mass is located above the pivot point, tending to fall. To keep the system in balance, it is necessary to incorporate key elements, including a measurement unit that combines a 3-axis accelerometer and a 3-axis gyroscope, stepper motors as actuators, and a PIC microcontroller. After the mechanical and electronic construction of the robot, the next step is processing sensor data through developed software to obtain more precise and stable readings. Then, a PID controller is implemented, responsible for adjusting the position of the support point and the applied force to maintain the robot's balance continuously. The angle at which the robot is in relation to the ground is visible through an application that connects to the system via a Bluetooth module. During the project's development, it was possible to recognize the importance of certain aspects to ensure the effective performance of the system. Firstly, there is the need for a robust physical structure that ensures the alignment of the robot's wheels and the correct distribution of its mass. Furthermore, it is essential to ensure the proper synchronization of the control loop with the previously defined sampling period to allow the controller to react consistently to possible disturbances. These findings play a crucial role in the successful development and operation of the system. © American Society for Engineering Education, 2024.