Numerical and experimental investigation on properties of miniature flexible joint torque

In order to study the properties of flexible joint torque in a certain motor pressure, a miniature flexible joint with silicone rubber elastomer was designed. The dynamic characteristics of flexible joint under 9 MPa vessel pressure were tested and the curves of torque versus vector angle for the flexible joint at different amplitudes and frequencies were obtained. The friction torque was obtained through the 0° vector angle torque and the spring torque was calculated by the near-linear part of the torque versus vector angle curve. In addition, the influence of excitation frequency and amplitude on the three kinds of torque were studied. Results show that coulomb friction torque increases as the excitation amplitude increases. The viscous friction torque increases with the increase of swing frequency. The spring torque and the total ratio torque increase as the swing frequency increases while decrease with the amplitude increases in a certain range and then increases as the amplitude in-creases.