Research: Project 2

Figure 1: A single-link flexible robot.

Goal

To compare various modeling approaches for flexible robots and assess the ease or difficulty of using those approaches for the design of real-time feedback control systems for motion control and vibration suppression

Background

Figure 1 shows a single-link flexible robot. The robot is made up of a DC motor driving a cantilever beam (this system is sometimes referred to as a slewing beam). The input to the system is a voltage to the motor. The outputs include a quadrature encoder signal giving the position of the motor , an angular velocity sensor measuring , and a strain gage measuring the vibration of the beam.

There are several approaches to modeling this system that have been presented in the literature:

1. Fully nonlinear finite element analysis (FEA)

2. An FEA approach focused on correcting for geometric foreshortening [1]

3. An FEA approach based on perturbation methods [2]

4. The transfer matrix method (TMM)

Approach

Each of the modeling approaches mentioned above has strengths and weaknesses, often trading off computational difficulty with theoretical accuracy. This project will compare these different modeling approaches with one another and discuss differences in simulation results. The project will then move on to investigating the feasibility of using each model in feedback control design. One goal of the project will be to run some form of the simulations in real-time on embedded hardware in order to estimate unmeasurable states and simulate additional sensor locations. The control systems will be implemented on PSoC's (Programmable System-on-Chip) and/or PIC chips.