基于平面机构运动链的LEMs构型综合

Structural synthesis of LEMs based on planar kinematic chains

提出一种LEMs机构综合方法,该方法能够求解包含转动副和移动副,以及机架和主动件变换的LEMs机构综合问题。首先,构造平面运动链的杆组邻接矩阵,基于此杆组邻接矩阵,求解给定构件数和自由度数的所有平面机构的可能连接方式;其次,基于构件和自由度的数目,分析杆组的所有装配方式,构建杆组邻接矩阵的框架,依据一定的约束条件,将第一层及之后的杆组依次装配到主动件和机架或者前层杆组上,并且同步辨识同构体,从而获取只含转动副的所有平面机构构型;然后,将主动件的运动副类型以及不同类型的各级杆组分别代入前述所求得的平面机构构型,得到包含转动副和移动副,以及机架和主动件变换的所有平面机构构型;最后,用相应的柔顺片段代替刚性片段,完成LEMs构型综合。

Proposed a structural synthesis method of LEMs both with prismatic joint and revolute joint, which can solve the prob- lem of frame and driver link transformation. First, equate the LEMs in the plane with the planar kinematic chains, and then con- struct the group-based adjacent matrix of the planar kinematic chains, and to solve all possible connection mode of planar mecha- nism which is given the number of bars and degree of freedom. According to the number of bars and degree of freedom, analyze all the combination of Assur group, set up the frame of the group-based adjacent matrix, assemble the first stage and later groups to driver link and frame or former groups, and identify the isomorphism in synchronism, get all the connections of planar mecha- nism with only revolute pair, and then plug the joint types of driver link and all the different types of groups into the above planar mechanism connections, get all connections with prismatic joint and revolute joint and transformation of frame and driver link. Finally, restore the obtained planar kinematic chains to LEMs in the planar.