An optimal control approach to robust control of robot manipulators

Abstract

Abstract-We present a new optimal control approach to robust control of robot manipulators in the framework of Lin et al [7]. Because of the unknown load placed on a manipulator and the other uncertainties in the manipulator dynamics, it is important to design a robust control law that will guarantee the performance of the manipulator under these uncertainties. To solve this robust control problem, we first translate the robust control problem into an optimal control problem, where the uncertainties are reflected in the performance index. We then use the optimal control approach to solve the robust control problem. We show that the solution to the optimal control problem is indeed a solution to the robust control problem. We illustrate this approach using a two-joint SCARA type robot, whose robust control is obtained by solving an algebraic Riccati equation.

Robust-Optimal Control of Electromagnetic Levitation System with Matched and Unmatched Uncertainties: Experimental Validation

“…However, the undesired oscillations are prominent in the cases of matched uncertainty with Rs and unmatched uncertainty. The figures (32), (33), (34), and (35) shows the control input with the actual mass of the ball and the +25% change in the mass of the ball for the different uncertainties. The figure clearly illustrates that the control input remains near to its value as discussed in section (6).…”

“…The optimal LQR control based on the HJB equation is established for the magnetic levitation system for infinite and finite time with quadratic performance index [31]. An HJB equation-based robust optimal control approach is established for different uncertainties for the control of robot manipulator [32]. The robust-optimal approach using the HJB equation and neural network for the nonlinear system is proposed with fixed-time convergence [33].…”

Robust Control Based Stability Analysis and Trajectory Tracking of Triple Link Robot Manipulator

“…These systems have various application in many domains such as automation, spacecraft, surveillance Medical etc. In this paper Robust control technique has been propound for tracking control of manipulator systems and Lyapunov based stability analysis also discussed to show the effectiveness of the controller [14]. The main advantage of the controller is that it is very easy to implement.…”

“…As even single link manipulator is nonlinear in nature so conventional control technique is not suitable for the control of multilink manipulator as nonlinearities increasing in a drastic manner [10]. In past years, many robust control techniques have been proposed to overcome nonlinearities and disturbances for control of robot manipulator [11][12][13][14][15].…”

Preview Control of Trajectory Tracking for Servo System Based on Optimal Preview Control Method

“…Suppose the target value signal from the present time (i) to the future step M R , as well as to the interference signal of step M d are all known. Based on previous research (Liao, Cui, & Shen, 2009) and (Lin & Brandt, 1998), the optimal control input with feedforward compensation of system (1) is achieved as the following:…”