الفهرس 
Chapter 1 : IntroductionOnly 14 pages are availabe for public view
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Abstract
The dynamic analysis or modeling is an important consideration when designing and controlling robotic manipulators.The dynamic behavior may sometimes be neglected either by arguing that is it not significant or that the error introduced by doing so can be compensated for by the control system.In fact, these assumptions are valid for slow motions and small payloads.For fast motions and high payloads,the dynamic effects of the system will become significant.Most past research efforts on studying the dynamic analysis of parallel manipulators are concentrated on how to speed up the computations required to perform this analysis.However, using parallel and multiprocessor architectures lead to further speed up of the computations to suit real-time applications.Another problem, which must take part of interest of researchers in the field of dynamics, is how to consider the effect of joint friction on the performance of parallel manipulators.Joint friction is amajor problem in accurately controlling robot position during manipulator tasks involving small and slow motions.Friction as well as inertia effect represent acomplicated combination of the effects opposing the motion of robots.The presence of friction often imposes limits on positioning and force control for robot motions.Moreover, asignificant part of actuator force/torque is spent in overcoming joint friction.High performance tracking control of robots cannot be achieved if friction phenomena are not properly taken into account. Failure to compensate for friction in robotic applications may lead to large tracking errors in limit cycles when velocity reversals in the trajectory are required. Inorder to improve robot accuracy, it is important to accurately model robot dynamics which incorporates the effects of friction.