 ### Introduction to Scientific Programming Computational Problem Solving Using: Maple and C Mathematica and C

Author:
Joseph L. Zachary
Online Resources:
Maple/C Version
Mathematica/C Version

# Robotic Weightlifter Tutorial

In this tutorial we will use a simulator that will help you to understand the trigonometric model behind the robotic weightlifter presented in Chapter 11.

## Simulation

We will be using a weightlifting simulation throughout this tutorial. You can start it by clicking on the following button.

If you can read this, you don't need glasses. But you do
need a Java-compatible browser.

The simulator displays an idealized robotic weightlifter:

• The red lines represent the rigid body parts (the shin, thigh, and torso).

• The blue angles are alpha, beta, and gamma from Figure 11.2 of the text.

• The green angles are the knee and hip angles. (The ankle angle is always the same as alpha.)

• The horizontal lines show the y-coordinates of the knee, hip, and shoulder.

• The vertical lines show the x-coordinates of the hip, ankle/shoulder, and knee. (The x-coordinates of the ankle and shoulder are always zero.)

You can animate the weightlifting action by modifying the knee angle using the control at the top and then selecting Lift from the Robot menu. During the animation, you can watch the angle and coordinate values change.

Experiment with the simulation to get a better understanding of the geometry and trigonometry behind the model.

Last modified 31Oct96.