Control system design with on-line preview planning for desired signal

Abstract

We propose an online preview planning method for a desired signal and its application to 3-wheeled vehicle. We combine online planning for a desired signal and control system design. The planner is part of the control system. The planned desired signal is changed with the state of the servo system. Online planning has an advantage over traditional off-line planning in that the planning as well as the servo system reduces the influence of disturbance, parameter perturbation and initial value. Preview control can't be utilized for online planning because the future desired signal depends on the future and present state of the control system, but the proposed method uses the future restriction of the desired signal. By integration of preview planning and online planning, the planner can prevent the output of the controlled object from spilling over the permitted domain better than without preview planning. Online planning constructs a feedback loop and preview planning adds feedforward. The domain within which the 3-wheeled vehicle moves is usually restricted by various obstacles etc. It can be regarded as the restriction of the desired signal. Information of the obstacle within a certain distance can be given by the sensor. Online planner can use the information of the future restriction in advance. The vehicle can start to avoid the obstacle earlier than without preview planning. We show a simulation result.