Organization Name: Wuhan Digital Design and Manufacturing Innovation Centre Co., Ltd.

Project introduction:
Aviation manufacturing is one of the most important parts of BRICS cooperation, among which the polishing and activation of aircraft skins are the key processes to ensure aircraft performance and safety. At present, domestic aircraft skins polishing mainly depends on manual work. For example, it takes 30 people to work 3 days to polish the aircraft C919. As a result, manual grinding is labor-intensive and difficult to guarantee consistency, which becomes the pain currently troubling aircraft manufacturing. To tackle the problem and meet the national demands, our team developed an adsorption mobile processing robot, which can realize the robotization of skin polishing with high efficiency and high quality.

Climbing robot’s adsorbing movement on the surface with variable curvature, multi-sensor fusion algorithm and high consistency polishing are the key technologies of this project. 1) Adsorbing movement: The aircraft skins are made of non-magnetic materials such as aluminum alloy, which are not suitable for magnetic adsorption. Besides, with the wide range variable curvature of the aircraft skins, thetraditional negative pressure adsorption chamber is unable to keep sealing and fitting the adsorbed skins, leading to the desorption when the robot moves. Aiming at this challenge, our team designed a flexible adsorption cavity and invented a dynamic adjustment mechanism for the adsorption cavity attitude, which help the robot realize compliant adsorption with a wide curvature range. 2) Positioning: The existing multi-station external positioning systems represented by IGPS are expensive and encounter the problem of measurement dead spots. Our team proposed a multi-sensor fusion technology to achieve centimeter-level positioning at a40m scale. 3) Polishing: The area of aircraft skins is very huge (e.g. the superficial area of C919 is almost 600m2), which brings a higher requirement for the consistency of polishing quality. We invented a polishing unit that integrates various pose sensing sensors and uses a pneumatic constant force structure to achieve constant force polishing of the full profile with little duplicated and omissive area.

Our project is expected to replace manual operations, realize the innovation of efficient and high-quality polishing for aircraft skins by robots, and advance themanufacturing model. We have applied for 16 patents and conducted field verification in COMAC.