405 Lab 0xFF: Final Project

The final project for ME 405: Mechatronics, at California Polytechnic State University, consisted of designing a closed-loop response for balancing a ball on a platform.

The platform pivots in two planes of motion, and has two connections to two separate motors. These motors control a 4-bar linkage system which controls the tilt angles of the platform. The ball rests on the platform, which has a resistive touch panel for tracking the position of the ball in both X and Y directions.

Figure 1. Balancing platform as seen from the motor side.

This project spanned several assignments/weeks of the quarter. Thus, this project will be divided into several subsections to collectively represent the entirety of the work. See the list below to access the several parts of the project that led up to the final project.

Modeling and Controller Design: Homework Assignments

Before any code could be written to interface with the hardware of the balancing platform system, the system was modeled and simulated over the course of multiple homework assignments. The three sections below provide an overview of work done prior to working with the physical system.

• System Modeling: Kinetics and Kinematics
• Linearization EOMs and Simulating Closed-Loop Control
• Full-State Feedback

Hardware and Code Implementation

Once the system had been fully analyzed from a theoretical standpoint, it was time to interface with hardware and get the full integrated system working together to balance the ball. The following pages describe code and general theory of each hardware component, as well as system integration, controller testing, and the final results.

• Resistive Touch Panel: Locating the Ball
• DC Motors: Moving the Platform
• Quadrature Encoders: Measuring Motor Position
• User Interface (UI) and Controller
• System Integration: Task Scheduling, Data Sharing, and Data Collection
• Testing and Tuning: Balancing the Ball
• Final Results: Evaluation of System Performance

In total, this project provided a challenging, yet rewarding, exposure to common hardware within the mechatronics world. The full process of modeling, designing a controller, writing code, and tuning to achieve a working system is invaluable experience for future projects. Furthermore, learning to utilize task diagrams to plan out relations between various tasks added a new skill to our mechatronics background.

The final code can be seen at our online repository. Use the following link in order to view the code:

Lab0xFF Source Code