空间光学系统无扰动平台研究进展

Significance Space optical systems are essential for high-resolution astronomical observation, deep-space laser communication and gravitational-wave detection. Advancements are increasingly driven in space optical systems as space telescopes, laser communication terminals and laser interferometric detectors. These systems impose extremely stringent requirements on line-of-sight (LOS) pointing accuracy and stability. Pointing accuracy is defined as the angular deviation between the actual LOS of an optical system and its intended direction, while pointing stability refers to the angular jitter displacement of the LOS over time. However, these systems are greatly affected by the space environmental disturbances, such as microgravity gradients and solar radiation pressure. Concurrently, the host spacecraft generates internal disturbances from sources like thrusters, reaction wheels and cryocoolers. These microvibrations persistently excite LOS jitter, progressively degrading imaging quality, optical communication efficiency, or metrological accuracy. All these pose significant challenges to mission success. To mitigate micro-vibration-induced degradation of LOS performance, space optical systems widely employ vibration isolation techniques for stabilization, broadly categorized as passive or active isolation. Passive isolation attenuates vibration by absorbing energy through compliant or dissipative elements, offering simplicity, reliability and low cost. However, it inherently struggles to suppress low-frequency disturbances and lacks active LOS adjustment capabilities. Active isolation uses actuators to generate counteracting forces or torques, providing broad isolation bandwidth and enabling active LOS control. Nevertheless, conventional active systems retain a mechanical load path between the spacecraft interface and the optical payload. Residual vibrations transmitted through this path limit full-bandwidth stabilization efficacy. Disturbance-free payload (DFP) is a novel non-contact LOS stabilization platform. It conceptually decouples the optical system from the host spacecraft into two independent rigid bodies, interacting solely via non-contact sensors and actuators. This eliminates all micro-vibration transmission and connection stiffness inherent in traditional systems, achieving far superior pointing accuracy and stability. Owing to its advanced design and unprecedented performance, DFP has become a focal point in space optical stabilization research. Global teams have extensively explored DFP and demonstrated successful space applications. However, existing literature lacks systematic expositions or primarily covers early-stage investigations, neglecting rapid advancements of the past decade. A comprehensive review of current DFP research is thus both important and necessary for advancing space optical stabilization technology. Progress First, the system configuration and control strategy of DFP are explained (Fig.1), highlighting its advantages: high LOS pointing accuracy and stability, low stabilization cost, long lifetime and high reliability. DFP architectures are classified into four categories based on the type of non-contact actuator used, with the corresponding research progress summarized as follows: 1) single-axis linear actuator DFP features a simple architecture and flexible arrangement. Early experiments by the Lockheed Martin Advanced Technology Center (LMATC) validated planar three degrees of freedom (DOF) and spatial six-DOF DFP concepts (Fig. 3). Subsequently, the Shanghai Institute of Satellite Engineering and other groups developed an orthogonal eight-rod DFP (Fig. 7). 2) Two-axis linear actuator DFP is characterized by its compact size and is typically arranged in a Y or X configuration (Fig. 10). 3) Active magnetic bearing (AMB) DFP is rotationally dominant, offering larger angular travel and higher load capacity (Fig. 12). 4) Hybrid DFP augments the baseline architecture with contact mechanical actuators to achieve additional controllable DOF or extended stroke (Fig.14). Then, three key DFP technologies are analyzed: non-contact actuators, architecture design and stabilization control. The merits and drawbacks of each DFP architecture are summarized (Table. 1), and three critical control challenges are discussed in detail: internal collision avoidance, cable connection disturbances and degree-of-freedom coupling. Current applications of DFP in deep space laser communication and astronomical observation are presented, including the deep space optical communications (DSOC) project (Fig.17), NASA's next-generation telescope-the Large Ultraviolet Optical Infrared Surveyor (LUVOIR) (Fig.18) and the Chinese Hα Solar Explorer (CHASE) (Fig. 19). Finally, DFP development trends toward higher efficiency, autonomy and swarming capabilities are explored. Prospects are outlined for applications in space-based gravitational wave detection, distributed space telescopes, optical systems aboard satellites, aircraft, ships and vehicles. Conclusions and Prospects DFP employs a non-contact design that eliminates mechanical linkages inherent in traditional isolation systems, delivering unprecedented LOS stabilization performance. To meet stringent high-accuracy and high-stability requirements for space optical systems, DFP has progressed through theoretical development, proof of principle validation, key technology maturation, prototype fabrication and on-orbit demonstration. Successfully implemented in pioneering missions such as DSOC and CHASE, DFP has emerged as a critical LOS stabilization solution. Based on global research and flight heritage, DFP is projected to advance toward enhanced efficiency, autonomy and swarming capability-driving breakthroughs in core technologies. Future deployments will expand into more diverse mission scenarios, offering cost-effective commercial solutions for optical systems. These applications include satellite remote sensing, further broadening the technology's potential uses.