压电智能结构形状控制的迟滞非线性热力电耦合理论与实验研究

Large-aperture space antennas and lens with high shape precision are the important components of developing high-throughput space communication and high-resolution optical remote sensing equipment in the future. Shape control based on piezoelectric actuation is one of the key technologies to realize high-precision shape control of large space antennas and lens in orbit. However, the mechanical response characteristics of the space structures would be significantly changed by the combined influence of the thermal-mechanical-electrical coupling in space environment along with the hysteresis non-linear behavior of piezoelectric materials, which eventually reduces the shape control accuracy of the structure. In this project, the high-precision shape control of piezoelectric smart structures considering hysteresis under thermal-mechanical-electrical coupling field is studied, in which the theoretical study is supported by the experimental measurements and data analysis, the hysteresis non-linear multi-field coupling analysis theory of piezoelectric smart structures is developed from the establishment of thermal-mechanical-electrical multi-field coupled hysteresis non-linear constitutive model of piezoelectric materials, and the synthesis of thermal-mechanical-electrical multi-field coupling effect and hysteresis behavior on structural mechanical response characteristics is revealed. Finally, the shape control method with hysteresis compensation in thermal-mechanical-electrical coupling field is given. This project can promote the on-orbit application of piezoelectric shape control technology, and provide important theoretical and technical support for the development of large-scale and high-precision space structures in the future.

具备高精度型面指标的大口径空间天线/镜片是发展未来高通量空间通信与高分辨率光学遥感装备的重要组件，基于压电驱动的形状控制是实现大口径空间天线/镜片在轨高精度形状控制的关键技术之一，但空间环境的热-力-电耦合作用及压电材料的迟滞非线性行为会对大尺寸天线/镜片结构的力学响应特性产生显著综合影响，进而严重降低结构的形状控制精度。本项目以实验测量和数据分析支撑理论研究，对热-力-电耦合场下考虑迟滞行为的压电智能结构高精度形状控制展开研究，从建立压电材料的热-力-电多场耦合迟滞非线性本构出发，发展压电智能结构的迟滞非线性多场耦合分析理论，揭示热-力-电多场耦合作用及迟滞行为对结构力学响应特性的综合影响机制，最终给出热-力-电耦合场下具有迟滞补偿能力的结构形状控制方法。本项目的实施可推动压电驱动形状控制技术的在轨应用，为我国发展未来大尺寸高精度空间结构提供重要的理论和技术支撑。

面向空间大型天线和镜片的形状控制与高精度指向调节应用需求，开展了压电材料的热-力-电多场耦合条件下迟滞行为、补偿控制方法与压电作动器件设计三方面研究。针对空间结构形状控制需求，提出了基于压电材料形状记忆的形状控制方法，研究了压电形状记忆的迟滞行为及应变调节特性，并设计了相应断电位移可保持压电作动器，其断电可保持位移行程大于18 μm，断电可保持位移分辨率优于4 nm；针对空间天线高精度指向需求，设计了压电二维指向平台，基于支持向量机提出了压电平台动力学模型的高效建模方法，并提出了迟滞补偿的自适应控制方法，压电平台二维指向范围±0.6 mrad，二维指向分辨率优于15 μrad；针对空间结构的大载荷大范围和高精度调节需求，设计了融合尺蠖驱动与惯性驱动的混合式压电作动器，该作动器驱动行程大于±3 mm，负载能力大于500 N，断电可保持位移分辨率由于80 nm。本项目所研制的压电作动器已初步在天线指向、结构形状控制方面获得实验验证，为发展未来机械式在轨可重构天线及各类高精度光学天线提供了理论与关键驱动器件支撑。