Numerical Derivation-Based Serial Iterative Dynamic Decoupling-Compensation Method for Multiaxis Force Sensors

A novel serial iterative dynamic decouplingcompensation (SIDDC) method is proposed for multiaxis force sensors to solve their problems of cross-axis dynamic coupling interference and the main channel dynamic error. Specifically, based on the output coupling model of the sensor, the Jacobi, Gauss-Seidel (G-S), and successive over-relaxation (SOR) iterative methods are introduced into the sensor dynamic decoupling to solve the most critical problem of dynamic coupling interference. The frequency-domain analysis method of the iterative decoupling convergence characteristic is proposed, and the convergence characteristics of the three iterative methods are compared. Then, the frequency-dependent relaxation factorbased SOR_M iterative dynamic decoupling method, which may be more effective is put forward, and the construction method of the frequency-dependent relaxation factor with its amplitudefrequency characteristic meeting the specific demand is given in detail. Subsequently, the compensator of the sensor main channel is adopted to directly compensate the decoupling result for reducing the main channel dynamic error. In addition, according to the static coefficient matrix of the sensor output coupling model, the dynamic compensation result is reconstructed so as to ensure the static characteristic of the sensor before and after dynamic decoupling-compensation remain unchanged. Finally, the experimental data verifications of the proposed SIDDC method are performed for a three-component bar-shaped wind tunnel strain gauge balance. The verification results indicate that the proposed SIDDC method, especially the SOR_M iteration based method, is much effective for improving the dynamic performances of the multiaxis force sensors.