The fatal robot accident that brought work to a halt at a Volkswagen factory last week isn’t likely to repeat itself with future models of the industrial assembly arms from Japan’s FANUC Corporation if one of its most recent patent filings is anything to go by. Disclosed inside is a new design that could remove the risk posed to human operators in automated production lines once and for all.
The key detail to notice in the sketch is the dashed outline surrounding the robot’s base and jointed links, which represents a composite protective layer consisting of three parts. The protective designation is owed mainly to the outer cover, a soft elastic material that the filing says could be foam or rubber designed to cushion the hit for any workers caught in the way of the arm.
But the more important purpose of the coating is to transmit the force from the impact to the displacement sensor below, which is connected to a controller that automatically shuts off the robot if the magnitude of impact is exceeds certain thresholds. Were you to pull the arm apart and examine one of the links from above, here’s what the setup would look like:
The sensors themselves are not pictured, but the illustration does show the bottommost third portion of the protective layer, which is a rigid cover designed to provide resistance for the force absorbing coating and thus help increase detection sensitivity. The two layers are joined together by bolts as demonstrated above, or, in other implementations, industrial glue.