ZESZYTY NAUKOWE POLITECHNIKI RZESZOWSKIEJ 290, Mechanika 86 RUTMech, t. XXXI, z. 86 (4/14), październik-grudzień 2014, s. 501-516 Piotr GIERLAK 1 ADAPTIVE CONTROL OF THE SCORBOT-ER 4PC MANIPULATOR The problem of the manipulator tracking control is not trivial because the manipu- lator is a nonlinear object, whose parameters may be unknown and variable. The control law should enable the manipulator to behave correctly even when opera- tional conditions are changeable. The adaptive control system meets this require- ment. In this paper, both kinematic and dynamic equations of motion for the Scor- bot-ER 4pc are presented. The adaptive control algorithm was derived for this ma- nipulator. The presented control and adaptive laws guarantee practical Lyapunov stability. The results of verification of theoretical investigations are presented. Ex- periments were carried out on a work station which consists of the Scorbot-ER 4pc robotic manipulator, a computer with Matlab and dSPACE ControlDesk software and a DS1006 digital signal processing board. In the experiments, the specified point of the manipulator has moved on a desired circular path and the gripper of the manipulator was loaded in variable ways. The operation of adaptive control system was compared with the computed moment method. From the result of the comparison we can see that, in practice, the adaptive control gives better results. Keywords: robotic manipulator, manipulator’s dynamics, adaptive control system, Lyapunov stability 1. Introduction Robotic manipulators are devices which find different applications in many domains of the economy, for example in industry. The requirements in relation to precision and autonomy of manipulators are increasing as well as the tasks performed by them are more and more complex. The control of such complex systems is very problematic. Manipulators are objects with nonlinear dynamics, often with unknown and variable parameters which operate in changeable condi- tions. A change in operating conditions may result from the variation of mass and the mass moment of inertia of the objects which are carried by the gripper. The control system has to generate such control signals that will guarantee the 1 Autor do korespondencji/corresponding author: Piotr Gierlak, Rzeszow University of Technolo- gy, 8 Powstańców Warszawy Avenue, 35-959 Rzeszow, Poland, tel.: (17) 8651854, e-mail: pgierlak@prz.edu.pl