Presented in this paper is a semi active vibration control strategy based on the vibration absorber with adjustable clearance in elastic component. The control law of the clearance for alleviating the vibration of pr...Presented in this paper is a semi active vibration control strategy based on the vibration absorber with adjustable clearance in elastic component. The control law of the clearance for alleviating the vibration of primary system is derived by means of harmonic balancing technique so that the working frequency of the vibration absorber can trace the frequency variation of the harmonic excitation. The efficacy of the strategy is demonstrated by numerical simulations for attenuating the steady state vibration of a SDOF system and a 2 DOF system, which are under the harmonic excitation with slowly varied frequency in a wide range.展开更多
The actuator and sensor placement problem for active vibration control of large cable net structures is investigated in this paper.Since the structures exhibit closely spaced modes in the range of low frequencies,the ...The actuator and sensor placement problem for active vibration control of large cable net structures is investigated in this paper.Since the structures exhibit closely spaced modes in the range of low frequencies,the number of modes to be considered is quite large after modal truncation,while only a limited number of actuators and sensors are to be placed.This makes it hard to determine the actuator and sensor locations with the existing placement methods in the literature such as the methods based on the controllability/observability grammian.To deal with this issue,an actuator and sensor placement method based on singular value decompositions(SVD)of the input and output matrices is proposed,which guarantees the modal controllability and observability of the system.The effectiveness of the SVD based method is verified through numerical simulations in which comparisons are conducted between randomly-chosen locations and the optimal ones obtained by a genetic algorithm.展开更多
In wind tunnel tests,long cantilever stings are usually used to support aerodynamic models.However,this kind of sting support system is prone to vibration problems due to its low damping,which limits the test envelope...In wind tunnel tests,long cantilever stings are usually used to support aerodynamic models.However,this kind of sting support system is prone to vibration problems due to its low damping,which limits the test envelope and affects the data quality.It is shown in many studies that the sting vibration can be effectively reduced by using active sting dampers based on piezoelectric actuators.This paper attempts to review the research progress of piezoelectric vibration control in wind tunnel tests,covering the design of active sting dampers,control methods and wind tunnel applications.First of all,different design schemes of active sting dampers are briefly introduced,along with the vibration damping principle.Then,a comprehensive review of the control methods for active sting dampers is presented,ranging from classic control methods,like PID control algorithm,to various intelligent control methods.Furthermore,the applications of active sting dampers and controllers in different wind tunnels are summarized to evaluate their vibration damping effect.Finally,the remaining problems that need to be solved in the future development of piezoelectric vibration control in wind tunnel tests are discussed.展开更多
文摘Presented in this paper is a semi active vibration control strategy based on the vibration absorber with adjustable clearance in elastic component. The control law of the clearance for alleviating the vibration of primary system is derived by means of harmonic balancing technique so that the working frequency of the vibration absorber can trace the frequency variation of the harmonic excitation. The efficacy of the strategy is demonstrated by numerical simulations for attenuating the steady state vibration of a SDOF system and a 2 DOF system, which are under the harmonic excitation with slowly varied frequency in a wide range.
基金National Natural Science Foundation of China(11290153)。
文摘The actuator and sensor placement problem for active vibration control of large cable net structures is investigated in this paper.Since the structures exhibit closely spaced modes in the range of low frequencies,the number of modes to be considered is quite large after modal truncation,while only a limited number of actuators and sensors are to be placed.This makes it hard to determine the actuator and sensor locations with the existing placement methods in the literature such as the methods based on the controllability/observability grammian.To deal with this issue,an actuator and sensor placement method based on singular value decompositions(SVD)of the input and output matrices is proposed,which guarantees the modal controllability and observability of the system.The effectiveness of the SVD based method is verified through numerical simulations in which comparisons are conducted between randomly-chosen locations and the optimal ones obtained by a genetic algorithm.
基金supported by the Foundation of National Key Laboratory on Ship Vibration and Noise(No. 614220400307)the National Natural Science Foundation of China(No.11872207)+1 种基金the Aeronautical Science Foundation of China(No. 20180952007)the Foundation of State Key Laboratory of Mechanics and Control of Mechanical Structures(No. MCMS-I-0520G01)
文摘In wind tunnel tests,long cantilever stings are usually used to support aerodynamic models.However,this kind of sting support system is prone to vibration problems due to its low damping,which limits the test envelope and affects the data quality.It is shown in many studies that the sting vibration can be effectively reduced by using active sting dampers based on piezoelectric actuators.This paper attempts to review the research progress of piezoelectric vibration control in wind tunnel tests,covering the design of active sting dampers,control methods and wind tunnel applications.First of all,different design schemes of active sting dampers are briefly introduced,along with the vibration damping principle.Then,a comprehensive review of the control methods for active sting dampers is presented,ranging from classic control methods,like PID control algorithm,to various intelligent control methods.Furthermore,the applications of active sting dampers and controllers in different wind tunnels are summarized to evaluate their vibration damping effect.Finally,the remaining problems that need to be solved in the future development of piezoelectric vibration control in wind tunnel tests are discussed.
