“In the field of precision force control for collaborative robots, researchers have developed an in-situ integrated torque sensor using harmonic reducer flexible wheel deformation, and proposed a residual ripple compensation method based on Fourier series model to improve measurement accuracy. By analyzing the strain law at the bottom of the flexible wheel, a strain sensitive grid structure was designed, and a Fourier series model between the ripple and the angle of the wave generator was established for compensation. The test results show that this compensation method can effectively reduce the interference of residual ripple on the sensor output, providing a solution for the precise measurement of joint torque.”