DUAL CONFORMANCE INDEX-BASED ROBOTIC ARM PLACEMENT AND ADAPTATION

A method to decide the placement and structural adaptation of a roboti c arm with respect to a set of tasks is presented. Commercialized CAD/ CAM tools mostly limit the layout criterion of robotized cells to the reachability of a task. They furnish little assistance for the selecti on of the tool, the arm, or its placement. A robot-task conformance in dex is shown to overcome these limitations. Four volume ratios define the index. They are taken over a robot ellipsoid, a task constraints e llipsoid, and a minimum containing and a maximum contained ellipsoid. The strict equivalence of the four ratios is proven. A ''dual'' comput ational sequence and the concept of relevant singularities are introdu ced. This ''dual'' computation is shown to equal the original conforma nce index outside relevant singularities. The index is applied to case s of increasing difficulty. Internal motions of joints within the null space of the Jacobian are typically used to maximize the index. The c ases of simultaneous multitask optimization, tool definition, and robo tic structure definition are addressed. Its usefulness for the design of the cell layout is exemplified. (C) 1996 John Wiley & Sons, Inc.