Comparative analysis of actuator concepts for active gear pair vibration control

The development of control technology for large flexible structures must include practical demonstrations to aid in the understanding of controlled structures in space. To support this effort, a testbed facility has been developed to study practical implementation of new control technologies. The paper discusses the design of a second-order acceleration feedback controller that acts as an active vibration absorber. This controller provides guaranteed stability margins for collocated accelerometer/actuator pairs in the absence of accelerometer/actuator dynamics and computational time delay. Experimental results in the presence of these factors are presented and discussed. The primary performance objective considered is damping augmentation of the first nine structural modes. Comparison of experimental and predicted closed-loop damping is presented, including test and simulated-time histories for open- and closed-loop cases. Although the simulation and test results are not in full agreement, robustness of this design under model uncertainty is demonstrated. The basic advantage of this second-order controller design is that the stability of the controller is model-independent for collocated accelerometers and actuators.

Active vibration absorber for the CSI evolutionary model - Design and experimental results. [Controls Structures Interaction]

https://ira.lib.polyu.edu.hk/bitstream/10397/5192/3/paper_tso_Revised_1_1.pdf

Suppression of random vibration in flexible structures using a hybrid vibration absorber

A bibliography is given containing 1224 references published during 1999 and 2000 on piezoelectric and pyroelectric properties of materials and their applications. It includes journal articles and some conference proceedings. Complete bibliographic citations and additional information such as language and original sources of translations are given. This bibliography is the continuation of a series published semi-annually.

Guide to the Literature of Piezoelectricity and Pyroelectricity. 19

Four actuation concepts for the active suppression of gearbox housing mesh frequency vibrations caused by transmission error excitation from the gear pair system are modeled and compared by computing the required actuation force and amplifier power spectra. The proposed designs studied consist of (i) active inertial actuators positioned tangentially on the gear body to produce a pair of reactive force and moment, (ii) semi-active gear-shaft torsional coupling to provide tuned vibration isolation and suppression, (iii) active bearing vibration control to reduce vibration transmissibility, and (iv) active shaft transverse vibration control to suppress/tune gearbox casing or shaft response. Numerical simulations that incorporate a transmission error term as the primary excitation are performed using a finite element model of the geared rotor system (dynamic plant) constructed from beam and lumped mass/stiffness elements. Several key comparison criteria, including the required actuation effort, control robustness and implementation cost, are examined, and the advantages and disadvantages of each concept are discussed. Based on the simulated data, the active shaft transverse vibration scheme is identified as the most suitable approach for this application.

K. Ohsawa

Papers

Electromagnetic Actuator and Stacked Piezoelectric Sensors for Controlling Vibrations of a Motor on a Flexible Structure