Summary: | 碩士 === 國立中興大學 === 機械工程學系所 === 102 === This paper describes the design of six-axis force sensor which enable to measure three axis forces Fx,Fy,Fz and three axis moments Mx,My,Mz on robot’s wrist. Through the designing of the elastic body structure, it makes the strain gage of sensor to attach easily on the external surface. (External surface: The direction of normal to surface of structure is not blocked by other structures. On the contrary, it would be the internal surface.) It improves the difficulty of attaching strain gage to Maltese cross structure and make the process simpler. It also reduces the production cost greatly by automated production systems and the amount of the strain gages is also decreased. The two ways mentioned above lower down the high cost which was required to produce a six-axis force sensor. After designing and analyzing the elastic body structure, it would be produced and tested. Anticipating the six axis force sensor is able to be low cost and to reach or even excess the capability of it which are sold on the market.
Owing to new elastic body structure, sensor in this design that can measure three axis forces Fx,Fy,Fz and three axis moments Mx,My,Mz and reach mechanically decoupled by using only 12 strain gages, whereas Maltese cross structure uses 16 strain gages in the same bridge circuits. Further, strain gages with new elastic body structure all attach on the external surface of the structure which is easier than Maltese cross structure. It reduces the cost of producing the six-axis force sensor as well. The designed structure owns the capability that can make sensing element deposited directly onto structure by MEMS process. Therefore, it saves the human resources and time cost by automatic production. Moreover, there is no inaccuracy of strain gage attachment which caused by labor.
After the characteristic test of the developed sensor, maximum interference errors of the structure was 6.07%. However, there was the difference of 23% between simulated and practical situation. It meant that experiment must be improved, so that the evaluation of capability and value can be more accurate.
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