Coordinative Dynamics Analysis of a Parallel Manipulator With Three Grippers

Abstract

A kinetostatic model and a dynamics model of a parallel ma丑 ipulator (PM) with three grippers are establ四hed and a丑alyzed in the light of its application. First, the coordinative kinematics of this manipulator and three grippers are analyzed. Second, the kinetostatic formulae are derived for transforming the coordinative kinematics and forces applied on the grippers into the workloads applied on the movi吨 platform and the active/co丑 strained forc臼 and torques applied onto active legs. Third, the dynamics formulae are derived for solving dynamic active wrench of grippers a丑d PM by considering inertial mass of the grippers, legs and platform. Finally, a numerical example is given for illustrating application of kinetostatic model and dynamics formulae , and the dynamics solutions of this manipulator are veri丑ed by simulatio丑. KeyWordsParallel manipulator with multi grippers, coordinative dynamics, coordinative kinetostatics Notation DoF -degree of freedom; PM -paralle1 manipu1ator m , B -p1atform and base of PM 队 ， Bi -joints on m and B (i= 1, 2, 3) ωi -the ith claw

Design of in-pipe 3SPR/3RPS parallel manipulator and its kinestatics analysis

“…Let i be the angle between q i and g i , i be the angle between q i and h i1 , i be the angle between g i and p q ; i be the angle between q i and l i . Some above geometric formulae have been derived in [15]. The active leg l i in the ith foot mechanism is shown in Fig.2b.…”

“…The active leg l i in the ith foot mechanism is shown in Fig.2b. The angular velocity and the acceleration of l i have been derived in [15].…”

“…The active forces F ai (i=1, 2, 3) and the constrained forces F ci in {B} of the 3-SPR PM can be solved using a statics model of the 3-SPR PM in Ref. [15] as below,…”

“…Based on the principle of virtual work, the active force of l i with piston/cylinder in the ith foot mechanism is derived from Eq. (12) and [15] as follows:…”