A COMPARISON OF METHODS FOR COMPUTING FREQUENCY RESPONSE OF UNCERTAIN PLANTS

摘要

The frequency response of an inverted pendulum with a flexible arm, which is perturbed by six uncertain parameters nonlinearly, is calculated by the analytic method in Chen and Ballance (1999). This approach is compared with the extreme point, the parameter gridding and the probabilistic approaches. It is shown that the analytic approach provides a powerful tool for computing the frequency response of a wide class of nonlinear dependence uncertain plants. It is pointed out that for a plant withhard bounds, it is better to combine the probabilistic approach with the extreme point technique.