将一般过约束并联机构定义的过约束称为被动过约束,冗余驱动并联机构引入的过约束称为主动过约束,进而将过约束并联机构分为被动过约束并联机构、主动过约束并联机构和冗余驱动过约束并联机构.详细地描述了被动过约束并联机构和冗余驱动并联机构受力分析的国内外研究现状,提出了一种过约束并联机构受力分析的方法.该方法定义了分支约束力螺旋系刚度矩阵,考虑连杆及驱动器的弹性变形,推导得到了约束力螺旋系幅值的一般解析表达式.该方法适用于一般的过约束并联机构的受力分析,通用性较强.
Overconstraint defined on the general overconstrained parallel mechanism was called as passive overconstraint herein,the overconstraint introduced by the redundantly actuated parallel mechanism was called as active overconstraint.And then the overconstrained parallel mechanism was divided into passive overconstraint parallel mechanism,active overconstraint parallel mechanism and redundantly actuated overconstrained parallel mechanisms.The research status of force analysis for the passive and active overconstrained parallel mechanisms at home and abroad was described in detail.Therefore,a force analysis method for overconstrained parallel mechanisms was proposed.For the novel method,stiffness matrix of the supporting limb's constraint wrenches was defined,a general analytical expression for the solution of the constraint wrenches was derived by taking elastic deformations of the links and actuators into account.The proposed method can be applied to force distribution of general overconstrained parallel mechanisms,so it is of relatively strong versatility.