Autonomous Guided Vehicles (AGVs) are being deployed in -30°C freezers to replace human lift truck operators. However, the physics of thermal dynamics is blinding the robots. The navigation of an AGV relies heavily on 2D LiDAR (laser scanners) that map the environment.
In a freezer, the humidity is usually low, but when doors open to load a truck, warm, humid air rushes in. When this air hits the freezing cold LiDAR sensor window, condensation-or even a thin layer of frost-forms instantly. To the laser, this frost looks like a solid wall.
The AGV's safety logic kicks in: it detects an obstacle directly in its path and performs an emergency stop. It refuses to move. Because the AGV cannot wipe its own eyes like a human operator, it sits stranded until a technician enters the freezer with a cloth to wipe the lenses. Facilities are now installing heated sensor housings and small air-knife nozzles that blast the lenses with dry nitrogen to keep them clear, adding significant maintenance overhead to the "labor-free" robots.
