Method of improving the sensitivity of large-range six-axis force/moment sensor using the principle of stress concentration. (August 2022) - Feng, Mei
Highlights: Improved sensitivity of large-range force/moment (F/M) sensors. Analysis of the stress concentration effect of holes with different numbers, shapes, and positions. Timoshenko theory-based model for strain estimation on elastic body surface. Both FEA and experiments were performed. Improved sensitivity of F/M sensor, and good linearity and hysteresis error achieved. Abstract: This paper presents a method to solve the constraint of range and sensitivity of six-axis force/moment (F/M) sensors by using the principle of stress concentration. Taking the improvement of the sensor force sensitivity along the z-direction as an example, the implementation of the method is introduced. First, the stress concentration effect of holes with different shapes is analyzed using the finite element method, and the appropriate shape, position, and number of holes are determined. Second, a mathematical model for fast estimation of strain on the surface of an elastic body is established, which can be used to quickly determine its approximate size with different range and sensitivity requirements. Finally, the method was verified using calibration tests. The results show that this method can effectively improve the sensitivity of a large-range F/M sensor and ensure that the sensor has good linearity and hysteresis error, thus satisfying the design requirements of sensors.