Force-assembly with friction
Force-assembly with friction
复制标题
摩擦力装配
DOI：
10.1109/70.313097
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发表时间：
1994
期刊：
影响因子：
--
通讯作者：
M. Peshkin
中科院分区：
文献类型：
--
作者：
J. Schimmels;M. Peshkin
以前，力组装已经被定义为组装过程，对于该组装过程，单个导纳控制律（即，单个标称速度结合力到运动的单个映射）可以保证给定配对部件的正确组装。作为一个试验台的应用程序的力组装，工件插入到一个夹具组成的多个刚性夹具元件（fixels）的解决。以前的工作在这方面已经表明，当工件/夹具接触是无摩擦和位置误差是无穷小的，总是存在一个导纳控制法，将确保正确插入到一个确定性的夹具的工件。当工件/夹具接触无摩擦时，工件/夹具接触力包含识别误差减小运动所需的相对位置信息。然而，工件和夹具之间的摩擦会对接触力中包含的几何信息产生干扰。本文件述及：1）识别具有摩擦力的力组装必须满足的条件，以及2）导纳控制律的优化的公式和结果，以获得对于给定工件/夹具组合将满足力组装条件的摩擦力的最大值。结果表明，当接触力不再是特征时，力组装失败。如果一种类型的未对准可能发生的接触力对于该类型的未对准是唯一的，则力是特征性的。>
Previously, force-assembly has been defined as an assembly process for which a single admittance control law (i.e., a single nominal velocity in conjunction with a single mapping of forces to motions) can guarantee the proper assembly of a given pair of mating parts. As a testbed application of force-assembly, the insertion of a workpiece into a fixture consisting of multiple rigid fixture elements (fixels) is addressed. Previous work in this area has shown that, when workpiece/fixture contact is frictionless and positional error is infinitesimal, there always exists an admittance control law that will ensure the proper insertion of a workpiece into a deterministic fixture. When workpiece/fixture contact is frictionless, the workpiece/fixture contact force contains the relative positional information required to identify error-reducing motions. Friction between the workpiece and fixture, however, provides a disturbance to the geometrical information contained in the contact force. This paper addresses: 1) the identification of the conditions that must be satisfied for force-assembly with friction, and 2) the formulation and results of an optimization of the admittance control law to obtain the maximum value of friction that will satisfy the force-assembly conditions for a given workpiece/fixture combination. Results indicate that force-assembly fails when the contact forces are no longer characteristic. Forces are characteristic if the possible contact forces that may occur for one type of misalignment are unique to that type of misalignment. >