Design and performance analysis of a robot flexible connection device based on quasi-zero-stiffness mechanism

Abstract

For suppressing the vibration excitation transmission from the robot to the elastic component during robotic handling, a new type of quasi-zero-stiffness flexible connection device (QZSCD) is designed. By introducing the tilt linkage on the basis of traditional quasi-zero-stiffness isolator with three oblique springs, the QZSCD can actively adapt to varying load conditions. According to the static equilibrium relationship, the conditions that the QZSCD has zero-stiffness at the equilibrium position are obtained. Then, the optimal structure parameters of the QZSCD are determined based on maximizing the system quasi-zero-stiffness interval. And the quantitative relationship between the angle of the tilt linkage and the load mass is investigated. Furthermore, a unified dynamic equation for the QZSCD under varying load conditions is established. The influences of the structural parameters, the tilt linkage angle, and the load mass on the vibration response and displacement transmission characteristics of the QZSCD are analyzed. Simulation and experimental results indicate that by actively adjusting the tilt linkage angle, the QZSCD can ensure good vibration transmission suppression performance under varying load conditions during the robotic handling of the elastic component.