基于螺旋理论三自由度并联机器人型综合新方法

并联机器人的构型设计即型综合是并联机器人设计的首要环节,基于螺旋理论,从并联机构运动链分类的角度,提出用约束添加法对三自由度并联机构进行型综合,让主动链控制所需的自由度,而从动链约束不需要的自由度;提出了相应主动链和从动链各种类型,并对约束链作了较详细的分类,通过不同组合可得到不同性能的新构型.最后通过实例进一步阐明这一方法.该方法使型综合步骤更简洁,只要选择与自由度数相同个数的主动链,并合理选择约束链就可以组合出新的并联机器人.

New Method of Structural Synthesis Based on Screw Theory for 3-DOF Parallel Robot Mechanisms

The configuration design or the structural synthesis is the key factor in parallel robot designs.A new method to synthesize the 3-DOF parallel mechanisms called the constraint accession is proposed according to the screw theory in view of the classification of kinematical chains,where the active kinematical chains control the necessary DOFs and the passive kinematical chains control the unnecessary ones.The relevant active and passive kinematical chains are put forward and the constraint chains are classified in detail.It is demonstrated by an example that new configurations can be obtained by assembling different kinematical limbs.The new method makes the procedure of configuration design simpler and easier.As long as the number of the active chains chosen is the same to that of DOFs and the corresponding constraint chains are chosen reasonably,some new types of PRM can be assembled.