To increase sensitivity of big scale six-axis force sensor

a strain sensor which can be used in mechanic arm end is designed. Crossbeam elastic body structure is used

and sensor has high stiffness and sensitivity under big scale by optimizing strain beam structure and reasonable arranging of strain gauge. The finite element method is used to testify the reasonable of stress distribution. A decoupling and calibration test is taken based on the least square calibration principle

and experimental results show that the sensor has good static performance

and the minimum sensitivity is 0. 375 m V / N

which can meet application requirement.