Automated fastening system

A robotic fastening system operative to autonomously fasten a first subassembly to a second subassembly at a plurality of fastening sites, the system comprising:

• a fastening tool arranged to deploy fasteners to secure portions of the first subassembly to the second subassembly at various ones of the fastening sites;
• a set of actuators arranged to move the fastening tool to the various ones of the fastening sites, wherein the fastening tool is movable along a longitudinal direction, a transverse direction, and a height direction;
• a proximity sensor fixed proximate the fastening tool and movable with the fastening tool;
• a controller circuit operative to individually control each of the set of actuators and to read an output of the proximity sensor, wherein the controller circuit is programmed to execute a fastening-tool movement routine to move the fastening tool to a first one of the fastening sites wherein:
• the fastening tool is initially moved toward a nominal expected position of the first one of the fastening sites according to a predefined movement profile;
• on approach of the fastening tool to the first one of the fastening sites, and while the fastening tool is in motion to the first one of the fastening sites an output of the proximity sensor is compared against first detection criteria;
• in response to satisfaction of the first detection criteria, a speed of the motion of the fastening tool is adjusted while the fastening tool is in motion to the first one of the fastening sites, and the output of the proximity sensor is compared against second detection criteria that is different from the first detection criteria;
• and
• in response to satisfaction of the second detection criteria, the fastening tool deploys a fastener to secure the first subassembly to the second subassembly at the first one of the fastening sites.