Optimal design of a cam-flexure clamp
This paper is concerned with the design of a Cam-flexure clamp, which is a single-body, elastic structure to hold a slender tube with adequate force without using any fasteners. The clamping is achieved via cam action by means of a custom-made tool with elliptical head. The device has to fit in a very restricted space of less than 0.1?0.1?0.1?, and it should provide a clamping force of at least while obeying constraints on the required clamping-displacement, yield strength of the material, and manufacturability. This device is an example of a flexible and strong design where the interplay among flexibility, stiffness, and strength is crucial for satisfactory performance. The design problem is approached in three different ways: the finite element analysis-based intuitive design, topology optimization, and analytical design. On the basis of the combined insight gained from these, it is systematically shown that the allowable size needs to be slightly increased to give a practically useful design. An analytical model is developed to compute how much more space is needed to meet the specifications. The approach taken for this specific device illustrates a general procedure that might be applicable to situations where a flexible structure needs to be designed for conflicting requirements of stiffness, flexibility and strength.
optimal design topology optimization compliant mechanism stress constraints stiffness and strength