Modeling and Experimental Investigation of an Active Angular Vibration Absorber

The active angular absorber for angular vibration control is proposed. Characteristics of the angular absorber are analyzed and an experiment is performed. The active angular absorber consists of a base and two identical voice coil actuators. The actuators have central symmetry and the coils are series connected to get the same current so that they output inertia forces with the same amplitude in opposite directions. There is a certain distance between the axes of the two actuators to produce a moment from the inertia forces, which can be employed to actively control the angular vibration. First, the mechanics of the angular absorber are presented. Then, the dynamic model of an angular vibration system with the absorber is demonstrated and the control law is proposed. Parameters of the absorber are discussed, showing that the absorber has the advantages of reliable structure and flexibility for installation. Next, numerical simulation is performed and the results show that the control method is effective and the simplification of the dynamic model is reasonable. Finally, a prototype of the absorber is produced and the angular vibration control experiment is conducted. Test results show that angular vibration with the amplitude of 1” level and at a frequency of 6 Hz can be attenuated by 93% to the level of the noise, while vibration at 0.1” level and 46 Hz can be attenuated by 80.7% to 0.01”. The control process is rapid and convergence is stable.