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Due to the inherent hysteresis characteristics of the smart material, the positioning accuracy of the piezo-driven manipulator was always decreased. Especially in multi-degrees-of-freedom (MDOFs) compliant manipulators driven by multismart actuators, the cross-coupled hysteresis among MDOFs decreased the positioning accuracy of such compliant platforms significantly. In this paper, the hysteresis feature identification and coupled hysteresis compensation of a piezo-driven XY manipulator was investigated. To establish the hysteresis characteristics of the piezo-driven manipulator, a modified Bouc–Wen model has been proposed, and a Genetic Algorithm-based Particle Swarm Optimization (GA-PSO) was adopted to recognize the parameters of the model. To improve the output performances of the manipulator, the decoupling controller of the XY micromanipulator was designed, and the driven voltages were modified using the estimated coupling displacements. The experiments validated that the modified Bouc–Wen model featured the ability to present the hysteresis process effectively, and the maximum prediction errors are 0.19 μm and 0.16 μm in the two directions separately. The coupled hysteresis displacement before and after implementing the decoupling controller in the X-direction was reduced from 0.56 μm to 0.15 μm, and the coupling effect is reduced by 73.2%, while in the Y-direction, the coupling effect was also decreased by 72.9%.

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In order to alleviate the problems of complex structure and low reliability of traditional Shape Memory Alloy (SMA) rotary actuator, a planar vortex actuator (PVA) based on SMA material was proposed to directly output torque and angular displacement. Based on the calculation method of PVA and the constitutive model of the phase transition equation of SMA, the mechanical model is established, and the pre-tightening torque, temperature, output torque, and rotation angle are obtained. The relationship expression between the tests has verified the mechanical model. The results show that the relationship between the excitation temperature and the output torque, the coefficient of determination between the calculated value and the tested value, is 0.938, the minimum error is 0.46%, and the maximum error is 49.8%. In the relationship between angular displacement and torque, the coefficient of determination between the calculated value and the test value is 0.939, the maximum error is 58.5%, and the minimum error is 28.0%. The test results show that the calculated values of mechanical model and experimental data have similar representation form.

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In order to provide an ultraquiet environment for spacecraft payload, a six-degree-of-freedom microvibration isolation device for satellite control moment gyro (CMG) is proposed in this paper. The dynamic characteristics of the microvibration isolation device are analyzed theoretically and experimentally. The dynamic equations of the microvibration suppression device are established by using the Newton–Euler method. The dynamic responses are numerically solved and the frequency-domain characteristics of the microvibration isolation device under base excitation are analyzed. The analytical results are first verified numerically, and the two results are in good accordance. The experimental apparatus is built, and the vibration isolation performance is investigated. The acceleration transfer function is measured and the influence of the excitation amplitude on the vibration isolation performance is performed. It is shown that the amplification factor at the vicinity of the resonance frequency is within 10 dB, and the vibration isolation performance is significant at higher frequencies. The vibration attenuation performance at the main frequency of the CMG (100 Hz) is more than 30 dB. The microvibration suppression device can effectively suppress the microvibration generated by CMG during orbital operation.

This article evaluates the wave velocity of a leptadenia pyrotechnica rheological elastomer (LPRE) microbeam surrounded by micro piezoelectric and porosity of functionally graded materials' (FGMs) layers. Different models of graphene nano plates (GPLs) for reinforcing the face sheet are assumed by adopting Halpin–Tsai modified micromechanics theory to obtain the Poisson's ratio and Young modulus of the smart layer. The material properties of the whole system as a viscoelastic state are hypothesized using the Kelvin–Voigt theory. The motion final equations are gained by utilizing the theory of Timoshenko and the couple stress model. An analytical solution method is adopted for computing the velocity of wave, cutoff frequency, and escape frequency from the motion final equations. The influences of different distribution and volume percent of GPLs, FGM properties as well as gradient index, the numeral parameter of any layer, damping of structure, and exerted voltage on the velocity of wave microbeam are studied. Moreover, it has been seen that a rise in the FGM index leads to reduced phase velocity, cutoff, and escape frequencies. Meanwhile, enhancing the volume percent of GPLs increases the wave velocity of the microstructure beam.