China develops robotic car to maintain FAST telescope featuring reflective aluminium plates

A group of Chinese engineers have created an autonomous robotic automobile capable of cleaning, repairing, and replacing parts on the country's Five-hundred-meter Aperture Spherical Radio Telescope (FAST), the world's biggest single-dish and most sensitive radio telescope. The telescope's reflecting surface is comprised of one-millimetre-thin aluminium plates. Maintaining 2,225 laser targets on a massive spherical dish with a receiving area of 30 football fields is difficult.

According to the Institute of Automation under the Chinese Academy of Sciences, which constructed the robot, the newly developed robocar can run in all directions and perform replacement jobs autonomously, even on a 56-degree steep slope. FAST features a 500-meter-diameter reflecting surface in a natural sinkhole in the karst rock terrain, concentrating radio waves on a receiving antenna in a "feed cabin" situated 140 metres (460 feet) above it. The reflector comprises perforated aluminium panels held together by a mesh of steel wires suspended from the rim.

The surface of FAST is built of 4450 triangular panels, 11 m (36 ft) on each side, forming a geodesic dome. Underneath, 2225 winches pull on connections between panels, deforming the flexible steel cable support into a parabolic antenna aligned with the required sky direction.

FAST's maintenance services have already employed the technology, considerably enhancing efficiency and decreasing safety hazards. FAST began formal operations in January 2020 in a naturally deep and circular karst depression in Pingtang County, Guizhou Province, southwest China, and formally opened to the public on March 31, 2021.