Cobots in Washdown: Hard Lessons on Packaging Lines

I keep getting asked to drop a cobot next to a carton sealer to save a headcount. In a food plant with nightly washdown, mixed SKUs, and short changeovers, that has bitten us more than it has helped. Cobots are slow, they struggle in spray and foam, and tooling drifts faster than anyone admits.

For 60+ ppm pick and place or case packing, a standard robot with real guarding, IP-rated components, and solid fixturing has been the reliable choice. Keep the interface simple: start, stop, estop, clear fault, counts. Let the robot controller own motion and recoveries. The PLC should run conveyors, sensors, and interlocks. EOAT needs pinned quick change, keyed air and vac, and a spare set on the shelf.

The real downtime killer is recovery. Build a clear-fault routine that retracts to a safe position, prompts the operator with photos, and verifies all sensors before restart. Use mechanical hard stops and datum brackets so you are not chasing pick points with vision every Monday. Simple photoeyes beat clever code when belts wander.

Where have cobots actually earned their keep on food lines for you, and where did you go back to a traditional robot after the honeymoon phase?