CHAPTER SEVEN
SIMULATION RESULTS
The purpose of this chapter is to demonstrate the performance of
controllers designed to solve the nonlinear servomechanism problem for the robotic manipulator system. The particular manipulator chosen for the demonstrations is a 2-link planar manipulator. Certain tracking and disturbance rejection applications are considered and the resulting control schemes are tested using computer simulations.
The Simulated System
As indicated, a 2-link planar manipulator is used to evaluate the performance of the control schemes. A schematic of this manipulator is
given in Figure 7-1. It is important to note that the manipulator has been selected to operate in the vertical plane with gravity acting downward. In addition, a disturbance force which acts vertically downward on the hand has been included. This will be the nature of all disturbances used in the simulations.
We have chosen a discrete-time controller as a means of demonstrating the control algorithms. Basically, the results from Chapter Five on digital implementation have been applied. In all cases, a 40 millisecond sample period is used. The combined plant and controller can be modeled by the discrete-time version of the scheme given in Figure 6-1.