Based on optical imaging and photoelectric detection, optical measurement systems in range, which include optical, mechanical, and electronic components, can be used as integrated equipment to measure and record the flight trajectory, attitude, infrared radiation characteristics, and visible light features of targets. Photoelectric measurement equipment, mainly represented by photoelectric theodolites, is the earliest and one of the most basic facilities applied in range for measurement. With the gradual expansion of the spatial area and the increase in the frequency of space activities in recent years, the contradiction between increasingly frequent missions and limited manpower is becoming more and more prominent. There are urgent requirements for measurement capability improvement of photoelectric measurement equipment in range. Under the premise of ensuring high-precision measurement and high-resolution imaging capability, the new generation of single-station measurement equipment prefers to possess the capabilities to acquire more information on target characteristics, adapt to compatible multiple platforms, and have stronger mobility.
As one of the most important teams with a long history and strong capabilities in the development of photoelectric measurement equipment in range in China, the team of Precision Instrument and Equipment R&D Center, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences has been committed to improving the comprehensive ability and efficiency of photoelectric equipment. Recently, its main research focuses on a number of key technologies, such as infrared radiation characteristics measurement, lightweight structure design, and integrated optical and radar measurement. The overall ability of photoelectric theodolites has been improved in terms of the expansion of the measurement band, measurement information acquisition, and multi-platform adaptability. This paper summarizes the current status and research progress of technologies related to photoelectric measurement equipment in range.
This paper summarizes the research progress of a number of key technologies related to photoelectric measurement equipment, such as infrared radiation characteristics measurement, lightweight structure design, and integrated optical and radar measurement, based on the relevant work of Precision Instrument and Equipment R&D Center, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences. Firstly, an infrared radiation characteristics measurement technique is introduced that is different from the traditional image feature recognition. It includes five infrared radiometric calibration techniques (Fig. 2), atmospheric transmission correction, self-developed atmospheric parameter calculation software, and a new process to measure target infrared characteristics (Fig. 3). The current status of related research and the challenges faced by future development are summarized. Secondly, the lightweight structure design technology of photoelectric measurement equipment in range is described. Three lightweight structure design methods are introduced which are suitable for photoelectric measurement equipment in range, including the main reflector, namely the main component of the optical imaging system (Figs. 5 and 6), and mechanical structures such as support components (Figs. 7-13). In addition to considering the conventional mechanical properties of the equipment, it is also necessary to ensure minimal surface aberration from the optical design point of view. The dynamic properties of the equipment should be considered for the purpose of transportation. Finally, integrated optical and radar measurement techniques are discussed. Two optical and radar integration schemes of building block architecture (Fig. 15) and common aperture (Fig. 16) are summarized. The optical-radar integrated detection mechanism can obtain new data outputs, enhance the observation capability of ground-based photoelectric equipment, and achieve multiple sources of target information via fusion detection.
The photoelectric measurement equipment in range uses optical imaging information to obtain flight information of the target. The target parameters can be further analyzed after error correction, space-time alignment, intersection calculation, and corresponding data processing. These are important procedures for the measurement and control systems of spacecraft launch and recovery and the detection of multiple types of military targets. The main development trends of current photoelectric measurement equipment include simplifying usage, enhancing flexibility, lowering the price-quality ratio of single-station equipment, and improving the techniques of infrared radiation characteristic measurement, lightweight structure design, and integrated optical and radar measurement.
To meet the challenges of the complexity of measurement conditions and the diversity of measured targets, photoelectric measurement equipment needs to be able to achieve the diversification of information acquisition, the expansion of the measurement band, and multi-platform mobile station deployment while ensuring high-precision measurement and high-resolution imaging capability. Based on the existing demand for range measurement, boosting the development of the aforementioned technologies can promote the integrity, convenient operation, and reliable use of photoelectric measurement equipment in range. These factors are of great significance for enhancing the capability of photoelectric measurement equipment in range.
