摘要
“高分五号”卫星搭载的可见短波红外高光谱相机AHSI是我国高分专项的核心载荷之一。现有离轴三反相机结构设计多应用于可见光相机及多光谱相机,而高光谱相机则由望远镜、光谱仪及探测器组成特殊架构,AHSI光路长达3 m,包含3套离轴系统及22个离轴光学元件,导致系统在有限空间内复杂度及敏感性高,结构设计需解决复杂光路布局与空间环境稳定性挑战。研究基于新材料的相机一体化结构构型,是AHSI结构设计亟待解决的主要问题。首次系统性揭示了AHSI材料选型、结构设计、仿真分析与试验验证全流程。高光谱相机采用55%高体分SiCp/Al复合材料作为光机系统主支撑结构材料,结构设计采用将离轴三反望远镜、奥夫纳光谱仪及探测器等一体集成于复合材料光机框架上,实现了复杂紧凑系统布局、高刚性、高稳定性与轻量化的协同优化,采用超声波辅助梯度钎焊工艺完成光机框架组合焊接,通过有限元分析和力学试验验证了相机结构设计强度和刚度特性。高光谱相机在轨成像质量及辐射特性测试结果与地面保持一致,充分证明了高光谱相机结构设计有效性和稳定性。AHSI是国际上首台同时兼顾宽覆盖和宽谱段的高光谱相机,为我国国土资源调查等国家重大战略需求提供了有力支撑。
The Visible and Shortwave Infrared Hyperspectral Imager onboard the Gaofen-5 satellite is one of the core payloads of China′s high-resolution Earth observation program.Existing structural designs for off-axis three-mirror cameras are primarily applied to visible or multispectral imagers,while hyperspectral imagers feature a specialized architecture composed of a telescope,a spectrometer,and detectors.The AHSI optical path spans 3 meters,incorporating three off-axis systems and 22 off-axis optical elements,resulting in high complexity and sensitivity of the system in a limited space.The structural design faces challenges in balancing intricate optical path integration with stability under space environmental conditions.A critical task lies in developing a novel integrated structural configuration based on advanced materials.This study systematically reveals the full process of material selection,structural design,simulation analysis,and experimental validation for AHSI.The hyperspectral imager employs 55%high-volume fraction SiCp/Al composite material as the primary support structure for the opto-mechanical system.The structural design integrates the off-axis three-mirror telescope,Offner spectrometer,and detectors into a unified composite opto-mechanical framework,achieving synergistic optimization of compact layout,high rigidity,stability,and lightweight performance.The framework assembly was welded using an ultrasonic-assisted gradient brazing process,and the structural strength and stiffness were validated through finite element analysis and mechanical testing.On-orbit imaging quality and radiation characteristics of the hyperspectral imager remain consistent with ground-based results,fully demonstrating the effectiveness and stability of the structural design.As the first hyperspectral imager globally to simultaneously achieve wide coverage and broad spectral range,AHSI provides robust technical support for national strategic demands such as land resource surveys.The visible and shortwave infrared hyperspectral imager(AHSI)onboard the Gaofen-5 satellite represents a core payload within China′s high-resolution Earth observation program.Unlike conventional off-axis three-mirror cameras primarily used for visible or multispectral imaging,hyperspectral imagers require a specialized architecture comprising a telescope,spectrometer,and detector array.The AHSI features an extended 3-meter optical path integrating three off-axis systems and 22 off-axis optical components,presenting significant challenges in terms of structural complexity,alignment precision,and environmental robustness within constrained space.To address these challenges,this study presents the design and implementation of a novel integrated structural configuration using advanced composite materials.A systematic methodology encompassing material selection,structural design,simulation analysis,and experimental validation is established.The opto-mechanical framework utilizes a high-volume fraction(55%)SiCp/Al composite as the primary structural material,offering superior stiffness-to-weight performance.The design unifies the off-axis three-mirror telescope,Offner spectrometer,and detector assemblies into a compact and rigid composite structure,optimizing mechanical stability and mass efficiency.The framework is fabricated using an ultrasonic-assisted gradient brazing process to ensure precise bonding and structural integrity.Structural strength and stiffness are confirmed through finite element modeling and mechanical testing.On-orbit imaging results show strong agreement with ground-based calibration data,verifying the design′s environmental adaptability and long-term stability.As the first hyperspectral imaging instrument worldwide to achieve simultaneous wide swath coverage and broad spectral range,AHSI demonstrates the viability of advanced composite-based structural solutions for complex spaceborne optical systems.It delivers critical technical support for strategic national applications,including land resource management and environmental monitoring.
作者
刘书锋
刘银年
曹开钦
柯有龙
贾晓伟
Liu Shufeng;Liu Yinnian;Cao Kaiqin;Ke Youlong;Jia Xiaowei(Shanghai Institute of Technical Physics of the Chinese Academy of Sciences,Shanghai 200083,China;State Key Laboratory of Infrared Physics,Shanghai 200083,China)
出处
《仪器仪表学报》
北大核心
2025年第5期70-80,共11页
Chinese Journal of Scientific Instrument
基金
国家高分辨率对地观测系统重大专项(A0106/1112)项目资助。
