A directional deflection sensor beam for very small force/torque measurement

We proposed an H-slit type parallel beam, which can be effectively utilized to achieve a highly unidirectional deformable structure for force/torque sensors. The structure is an extension of the parallel beam structure. And hence, the proposed design structure will result in 4-bar link closed mechanism the joints of which are deformable, so the strain gauges are fixed at these positions. This is the basic idea and unique feature of our proposed design. The H-slit beam can be used to measure very small-generated forces. In this paper, we present above characteristics of the both beam structures with finite element method (FEM) analysis, and outline of a small force/torque sensor using H-slit beams. Moreover reported in this article is over load protection mechanism, which exhibits beam´s effectiveness and its ability, to withstand overload conditions without much deformation. This is due to the protection provided in the cross section of the beam.