Abstract: Analytic tools and basic concepts are developed for designing adaptable fixture layouts and planning multifinger’s grasp. Restraint cone, freedom cone and related restrained freedom and degree of freedom nr edefined as quantitative and qualitative indices for kinematic modeling, analysis and characterization of grasping and fixturing. Emphases are put on the condition for a fixture layout to locate a given workpart uniquely at a distred location, the condition of accessibility for loading and detachability for unloading and condition of form closure for a grasping. The criteria of form closure for grasping, uniqueness for positioning and accessibility for loading are derived, and the corresponding algebra tic criteria can be used for computer aided grasp planning and design of adaptable fixture.

Key words: 定位夹持, 机器人, 夹具, 抓取机构