Project Overview

Abstract

The main goal of this project was construction of a small (~1 foot tall), two-wheeled, self-balancing robot similar to a Segway.  Such a device is a type of inverted pendulum.  The project was deemed appropriate because completion would require use of skills from multiple disciplines of engineering and physics.  Some of the major tasks required were mathematically modeling the device from equations of motion in Matlab/Simulink, drawing CAD schematics of the physical apparatus, programming a microcontroller, and physically wiring all required electronic hardware together.  In addition to the primary goal of a self-balancing prototype, one “stretch” goal conceived to be attempted after the primary goal was achieved was position control.  This was never attempted but remains possible if this project is to be continued.

Objectives and Main Components

-Main Components: Orangutan SCP-1284p Microcontroller, Inertial Measurement Unit (IMU), Bluetooth Module

-The IMU contains sensors that were used to measure the tilt angle.  This information was sent to the microcontroller

-The microcontroller then uses a PID Controller algorithm to analyze the data and set the motor speeds accordingly

-Bluetooth communication was used to send commands to the robot (reset, power down, set PID values)

What was accomplished:

-Structure of robot with main components implemented

-Simulation of control system

-CAD model

-Partially working prototype

-Bluetooth communication

Difficulties/Setbacks:

-Difficulty securing wheels to motor shaft

-Due to the complicated device structure the device could not be modeled with complete accuracy

-This would have been helpful in determining optimal PID Control constants        

 Future improvements/Suggestions:

-Adjust PID values for stability

-redistribution of weight