As mentioned earlier, a simple linear feedback control law can be used to control the robot manipulator for positioning and trajectory tracking. For this purpose, a PID controller simulator was developed to enable testing and analyzing the robot behavior using this control strategy. Using this control scheme helps us avoid the complex (and almost impossible) task of determining the robot parameters for our 3-link prototype robot. One of the most complicated parameters is the inertia tensor matrix for each link, especially when the links are non-uniform and has complicated shape.
This simulator has a user friendly interface that enables the user to make on-line changes to any of the feedback coefficients and the forward gains. It can also read a pre-defined position trajectory for the robot to follow. It will also serve as a monitoring system that provides several graphs and reports. Figure 5 shows the interface window of that simulator.