TRIPOD STIFFENING USING CLAMPING PLATES WITH NO INCREASE OF MOVING MASS

In this paper, a new method is presented for stiffening a tripod made of fixed-length legs. The idea is to add a pair of clamping plates to each leg. In doing so, the out-of-plane motion of the leg is fully constrained, thereby significantly increasing its bending stiffness. Compared to the existing designs, the dvantage of this new design is that the clamping plates are the non-moving parts, therefore not contributing to the moving mass. As a result, the tripod can still be made very compact with light moving mass. To facilitate the design of the clamping plates, a method is proposed for analyzing the workspace of the sliding leg so that the shape of the clamping plates and the location of the clamping point can be properly selected. This design has been implemented on an existing tripod for polishing applications. Both theoretical and experimental results have shown the effectiveness of this new design.