Stability and performance of supercritical inerter-based active vibration isolation systems

2021 ◽  
pp. 116234
Author(s):  
D. Čakmak ◽  
Z. Tomičević ◽  
H. Wolf ◽  
Ž. Božić ◽  
D. Semenski
2007 ◽  
Vol 12 (5) ◽  
pp. 533-539 ◽  
Author(s):  
Hongling Sun ◽  
Kun Zhang ◽  
Haibo Chen ◽  
Peiqiang Zhang

Author(s):  
Fabian B. Becker ◽  
Martin A. Sehr ◽  
Stephan Rinderknecht

This paper deals with active vibration isolation of unbalance-induced oscillations in rotors using gain-scheduled H∞-controller via active bearings. Rotating machines are often exposed to gyroscopic effects, which occur due to bending deformations of rotors and the consequent tilting of rotor disks. The underlying gyroscopic moments are proportional to the rotational speed and couple the rotor’s radial degrees of freedom. Accordingly, linear time-varying models are well suited to describe the system dynamics in dependence on changing rotational speeds. In this paper, we design gain-scheduled H∞-controllers guaranteeing both robust stability and performance within a predefined range of operating speeds. The paper is based on a rotor test rig with two unbalance-induced resonances in its operating range. The rotor has two discs and is supported by one active and one passive bearing. The active support consists of two piezoelectric stack actuators and two collocated piezoelectric load washers. In addition, the rig is equipped with four inductive displacement sensors located at the discs. Closed-loop performance is assessed via isolation of unbalance-induced vibrations using both simulation and experimental data. This contribution is the next step on our path to achieving the long-term objective of combined vibration attenuation and isolation.


2018 ◽  
Vol 418 ◽  
pp. 163-183 ◽  
Author(s):  
N. Alujević ◽  
D. Čakmak ◽  
H. Wolf ◽  
M. Jokić

Author(s):  
Tanakorn Tantanawat ◽  
Zhe Li ◽  
Sridhar Kota

Compliant mechanisms have been designed for various types of applications to transmit desired forces and motions. In this paper, we explore an application of compliant mechanisms for active vibration isolation systems. For this type of application, an actuator and a compliant mechanism are used to cancel undesired disturbance, resulting in attenuated output amplitude. An actuator provides external energy to the system while a compliant mechanism functions as a transmission controlling the amount of displacement transmitted from the actuator to the payload to be isolated. This paper illustrates, based on preliminary results of finite element analyses (FEA), that a compliant mechanism equipped with an actuator can be used as an active vibration isolator to effectively cancel a known sinusoidal displacement disturbance at low frequencies by using a feedforward disturbance compensation control. The nonlinear FEA shows that a sinusoidal displacement disturbance of 6.0 mm amplitude is reduced by 95% at 3.9 Hz and 91% at 35.1 Hz with a sinusoidal displacement controlled input of 0.73 mm amplitude.


2020 ◽  
Vol 66 ◽  
pp. 507-518
Author(s):  
Jinsoo Choi ◽  
Kihyun Kim ◽  
Hyoyoung Kim ◽  
SeokWoo Lee

Sign in / Sign up

Export Citation Format

Share Document