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Techniques used for structural health monitoring and its application: A review
Published in Alka Mahajan, Parul Patel, Priyanka Sharma, Technologies for Sustainable Development, 2020
Gaurav Raj, Nirav Chaudhari, Arihant Jain, Mamta Sharma
Active vibration control is a method of applying an equal and opposite force in response to an external force. This helps in canceling the vibrations and providing stability. This technique is very useful as in modern world, the vibrations caused due to seismic waves often lead to enormous loss and have a devastating effect on the humankind, machinery used in industries and Infrastructures [5]. A successful example of AVC can be seen in helicopters. Additionally, this technique also provides more comfort with reduced weight. Components of active vibration control are as following: A base with a number of active driversAccelerometer to measure acceleration in all the 3 dimensionsAn electronic amplifier to amplify and convert the signals from accelerometers into electrical signals.In the case of large systems, pneumatic or hydraulic components are used as they higher power drive is required.
Processors and processing systems
Published in You-Lin Xu, Jia He, Smart Civil Structures, 2017
To actively control the structure, a key task is determining the appropriate control force which counts on control algorithms. The control algorithm is implemented by means of software in the computer for generating control force based on the measurements obtained from the sensors. The control algorithm should achieve the control objective, such as the maximisation of the reduction of structural response with the minimum control energy or control force. However, more reduction of structural response requires more control energy. Hence, a performance index is used in this situation to find a compromise between the need to reduce structural response and the need to minimise control energy. Different quantification of performance indices produces different types of algorithms. Diverse control algorithms are available for active vibration control such as optimal control, modal control, sliding mode control, H2 and H ∞ control, adaptive control and artificial intelligent control. A detailed discussion on these control algorithms can be found in Chapter 9.
Motor Vibration and Acoustic Noise
Published in Wei Tong, Mechanical Design and Manufacturing of Electric Motors, 2022
Active vibration damping is to actively reduce the response amplitude of the system within a limited bandwidth near the natural frequencies of the system. It offers a promise of high efficiency without the restrictions of passive methods. Active vibration control involves monitoring vibrations of a structure and utilizing the vibration signal to generate a force with the proper phase and amplitude to attenuate the vibration. An additional advantage of an active approach is the ability to supply a vibration signal that can be used independently for monitoring the vibration environment.
Active vibration control of smart beam by μ -synthesis technology: modeling via finite element method based on FSDT
Published in Mechanics of Advanced Materials and Structures, 2023
Shubo Zhang, Ye He, Lei Fan, Xiaoan Chen
In active vibration control, piezoelectric plates have been widely used as sensors and actuator [27]. There are mainly two types of active vibration control: feedforward control and feedback control. Feedforward control needs the excitation signal of the structure, so vibration cannot be controlled by feedforward control. Feedback control can be classified into output feedback and state feedback. Methods of modern control design mainly includes: LQR and LQG (static state feedback) control [28], PID and PD control [6], VSC (sliding mode control) [29], control and control [30], MPC (model predictive control) [31], and -Synthesis (robust control) [32, 33], etc. In addition to active and passive vibration controls, a self-control method combining the passive damping capabilities with the active control properties was presented in [34].
Active control of free and forced vibration of a rotating FG cylindrical shell via FG piezoelectric patches
Published in Mechanics Based Design of Structures and Machines, 2023
Mohammad Jafari Niasar, Ali Asghar Jafari, Mohsen Irani Rahaghi, Shahin Mohammadrezazadeh
Due to the adverse effects of vibration, employing an effective method for vibration suppression could be beneficial. Using closed-loop control with smart materials, such as piezoelectric, is a precise method of vibration attenuation. This method commonly employs piezoelectric materials as sensors and actuators. The direct piezoelectric effect is directly related to the applied strain (Chopra and Sirohi 2013) and can be used in sensor applications. On the other hand, the converse piezoelectric effect produces mechanical strain due to applied electric field (Chopra and Sirohi 2013) and can be used in actuator applications. The advantages of active vibration control through smart materials over other control methods are high accuracy, high efficiency, and more desirable responses.