Landexplorer 01 has its own unique tricks for its debut combination and space skating

2022-05-12 0 By

This article is from:China News Service, Beijing, February 27 (Ma Shaxa Chen Bajuan1) Land Exploration 1 01 group B star on The 27th on the long March 4C carrier rocket successfully entered the preset orbit, will be launched in January A formation operation.It will provide strong space technology support for geological disasters, land survey, earthquake assessment, disaster prevention and mitigation, basic mapping and forestry survey, so as to achieve multi-use of one satellite and maximize the overall application efficiency of the satellite.Double star 1+1& GT;As a formation satellite, the biggest difficulty of landprobe 01 is the control of the orbiting mode of the double star.”It’s like pairs figure skating in the Winter Olympics, where two athletes jump hand in hand, spin, and perform difficult dance moves as they glide at high speed and in sync on the ice.”Wang Wenyan, deputy chief designer of the satellite at the Control Institute of the Eighth Academy of China Aerospace Science and Technology Corporation, explained, “A and B stars in orbit also have A pair of invisible hands holding together, which we call the ‘baseline’.”In order to accurately see the height changes of mountains and vegetation in a period of time, it is necessary for the two satellites to return to the same target point and maintain the same relative position relationship for observation after each regression cycle.This invisible “baseline” is also a measuring stick that defines the relative position of the binary stars at their intended viewing point each time they arrive.”When orbiting, the two satellites are close to each other and observe at the same time, just like two human eyes. One eye can only see the plane, but the two eyes can see the height and depth, which can be used for mapping steep heights and forest vegetation,” Wang said.The formation of binary stars A and B will also change according to the latitude of the region they are mapping, so as to switch between leading and supporting stars.”For example, in low-latitude mapping, star B moves at A certain distance and Angle relative to Star A.When the satellite reaches mid-latitude, it will change into A satellite and operate in A different state relative to B satellite, which will maximize the working capacity of the two satellites and enable the country to observe land using the optimal observation baseline.In order to make the two stars dance well in the “space waltz”, the eight-courtyard attitude orbit control subsystem team proposed and applied the long baseline formation and strict return to orbit cooperative control technology, so that the two stars can not only safely “dance”, but also accurately “appear”.Du Yaoke, chief designer of the attitude and orbit control subsystem of the LANDprobe 01, said that the “long baseline” is a feature that distinguishes the landprobe 01 from the previous binary formation.Compared with other synthetic aperture radar satellites, the radar carried by this group is in The L-band, with longer wavelengths. The mapping requires that the distance between the two stars orbiting is between 2 and 6 kilometers, and the satellite itself is also relatively large, resulting in the double star configuration several times larger, but the control accuracy is more stringent.To do this, the team applied a combination of high-precision accelerometers and connected closed-loop control.”Similar to the radar system in a car driving on autopilot, it feeds back the satellite’s speed increments in real time, allowing the satellite to calculate whether to ‘accelerate’, ‘slow down’ or ‘turn’ next.”Du said.At the same time, in order to achieve high precision spacetime revisit of the observed target point, the satellite must operate in a strict regression orbit designed by precise calculation.In the orbit mode, the two satellites should not only maintain the “absolute lane”, but also ensure the relative safety distance, which is the strict regression orbit cooperative control technology.Research team made the main pipe to keep, auxiliary astrology to form orbit star formation strategy, two stars through the communication between radio frequency link establishment between star star, in real time to confirm each other state, synchronous execution control instruction, and through the total factor independent grade of diagnosis, failure diagnosis and measures such as safe escape, provide multiple security protection.In addition, in order to let the two “big” can “stride fast run” and do “small fine tuning”, quickly and accurately execute the control system instructions, the development team for the double star each configuration of 36 thrusters, and adopted the “5N+1N” combination strategy.”The 5N thruster has more power, while the 1N thruster is more accurate, allowing for both control efficiency and control precision.”Du said.(after)