Magnetorheological damper for vibration reduction in a robot arm

In this study, we develop a novel damper prototype for robot manipulators of a mobile robot to perform rescue operations in extreme environments like battlefields. Shock vibrations occur when such robots drive over rugged terrain, adversely affecting both the robot and the rescued person. We propose a joint module that utilizes magnetorheological (MR) fluid to depress environmental impact vibrations. To do this, we first suggest a novel structure for our MR damper, with multiple working coils to augment the magnetic field intensity for the given volume; then, we perform dynamic simulations on the manipulator with the suggested MR damper installed, examining vertical impact acceleration and the driving torque generated in the joint module. The proposed damper can best reduce the amplitude of vibrations by about 90 % at 21 Hz and by about 30 % at the system’s resonant frequency of 22 Hz, which are the frequencies of interest as those lie around the natural frequency of the robot arm.