Chinese Academy Of Sciences Institute Of Automation Team Develops FAST Laser Target Maintenance Robot

Recently, the National Key Research and Development Program (NKRDP) project "FAST Operation and Maintenance Robot System for Major Science Infrastructure" has passed the acceptance of the Ministry of Science and Technology (MOST). Jing Fengshui group of Institute of Automation, Chinese Academy of Sciences, and the National Astronomical Observatory of the Chinese Academy of Sciences, Guizhou Radio Astronomical Observatory jointly developed the reflecting surface laser target maintenance robot as one of the landmark achievements, can efficiently complete the laser target cleaning, disassembly and replacement tasks, successfully realized the FAST reflecting surface on the fully automated maintenance of the laser target, for the "China Eye" to provide operation and maintenance support. Provide operation and maintenance guarantee for "China Sky Eye".
Five-hundred-meter aperture spherical radio telescope (FAST) is the radio telescope with the largest single aperture and the highest observation precision in the world. There are 2,225 laser targets distributed on the reflecting surface of FAST, which is an important part of its control system, just like the "eyes" of the reflecting surface, and needs to be maintained and replaced on a regular basis. However, the reflective surface is composed of aluminum plate with a thickness of only 1mm, which is difficult to bear the weight of a normal adult. At present, the reflective surface mainly relies on "microgravity spiderman" to carry out manual maintenance, which has the shortcomings of low maintenance efficiency, poor safety, and difficult to maintain the target targets under the environment of large slopes, and so on.
For the complex maintenance environment on the surface of FAST, the project team has broken through the technical problems of omnidirectional movement on the special surface with large gradient, three-dimensional measurement in complex environment, and autonomous spinning and screwing of abnormal bolts in non-structured environment, and completed the development of the target maintenance robot. The robot system as a whole consists of target maintenance execution system, omnidirectional motion platform and navigation system, and is capable of omnidirectional walking on the reflective surface, precise three-dimensional measurement of target position, dismantling and grasping of the old target, assembling and screwing of the new target, etc., and it can autonomously complete the replacement and cleaning tasks of the target and carry out the full-automatic target maintenance work.
In order to ensure the safety of FAST on-site maintenance, members of the project team carried out a long time debugging experiments on the robot under the simulated environment of high slope reflective surface, verifying the robot's mobile performance and target maintenance performance under the 56-degree extreme slope condition. After the adaptive debugging in the actual environment of Guizhou Radio Astronomy Observatory, the robot has been successfully applied to the replacement and maintenance of the laser target on the reflecting surface of FAST, which will strongly solve the problems of high-risk operation, low efficiency of manual maintenance, and constraints on observation under climatic conditions, and will greatly improve the efficiency and safety of FAST's maintenance operation.

(Left) Microgravity spider man on the reflective surface of FAST (Right) Laser target on the reflective surface of FAST.

FAST Laser Target Maintenance Robot

Robot testing on the FAST reflective surface

Group photo of team members, from left: Senior Engineer Jiang Zhiqian and Researcher Zhu Lichun of the National Astronomical Observatory of the Chinese Academy of Sciences (NAO), Researcher Jing Fengshui, PhD student Tao Rui and PhD student Fu Yichen of the Institute of Automation of the Chinese Academy of Sciences (IAAS), and Song Benning of the Guizhou Radio Astronomy Observatory (GRAS).