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This paper aims to present a multi-axis actuating approach to attenuate the bending and torsional vibration of the solar array through the reaction wheel (RW) actuators.

The motion equation of the solar array with the RW actuators is derived in modal coordinates for controller design. The reaction torques, induced by the speed change of the RW actuators, are controlled for vibration attenuation through the constraints on the actuators’ rotating speed. The proposed control approach is firstly verified with numerical simulation on the finite element model of a full-scale solar array. Experimental study of a simplified elastic plate model is subsequently performed for feasibility and validity investigation.

Both the numerical and experimental studies demonstrated the success of adopting RW as the actuator. Results from numerical simulation reveal that the vibration response peak can be reduced by 80% with 2% of mass increase by using the RW actuators.

It is demonstrated that the multi-axis actuating method using RW actuators has a great potential in vibration attenuation of the multi-panel deployable solar array.

An approach to reduce bending and torsional vibration of solar array based on RW actuators is investigated. Theoretical analysis, numerical simulation and experimental study are conducted to demonstrate the validity of the proposed vibration attenuation approach and its potential application in the spacecraft design.

The rest-to-rest movements for a spacecraft, such as attitude adjustment and orbital manoeuver, are likely to excite residual vibration of flexible appendages, which may affect the attitude accuracy and even result in severe structural damage. The purpose of this paper is to present an approach to attenuating the vibration of flexible solar array by using reaction flywheel.

The reaction flywheel installed on solar array served as an actuator to provide reaction torque to a structure according to a designed feedback control law. This torque can be considered as an artificial damping. Experiment on a scale model of the solar array is first performed to verify the effectiveness of this method. Numerical simulation on finite element model of a full-scale solar array is subsequently carried out to confirm the validity of this method for practical engineering application.

The vibration suppression effect on the structure using a reaction flywheel is deduced by theoretical analysis. Results from both experiment and numerical simulation reveal that the efficiency of vibration attenuation is promoted.

Improvements on control law are left for further study. Additionally, only the first-order bending vibration of the flexible solar array is attenuated, and further study is required for other types of vibration suppression.

An effective method is proposed for spacecraft designers to actively suppress the vibration of the flexible solar array.

A novel active vibration reduction scheme is proposed using a reaction flywheel to suppress vibration of the flexible solar array. This paper fulfils a source of theoretical analysis and experimental studies for vibration reduction measure design and provides practical help for the spacecraft designers.

This paper aims to empirically identify crucial international logistics policy enablers and to examine their impacts on logistics performance using survey data collected from 169 responding firms in Taiwan and 109 responding firms in the UK including logistics companies, freight forwarders, shipping companies, agencies and airline companies.

A multiple regression analysis is used as a method to empirically validate the research model.

Results indicate the five most important logistics policy enablers according to Taiwanese logistics firms are information technology system, inland transport linkage, simplifying the customs clearance procedures, ports and maritime transport and having a policy to ensure efficient service operation and multiplicity of services. In contrast, for the UK logistics firms, the five most important logistics policy enablers are telecommunications, information technology system, avoidance of unnecessary regulation, inland transport linkage and ports and maritime transport. Results also indicate that logistics policy dimensions in terms of regulation, integration, infrastructure and logistics education have a positive influence on firms’ logistics service quality and efficiency.

Theoretical and policy implications from the research findings on logistics policy between these two countries are discussed in this paper.