More pain sensors

It is difficult to mount A.s.a. H.'s pain sensors on moving parts. In the case of Lego beams connected by a pin or axle it may be possible to mount 2 thin metal washers between the 2 beams, one glued to each beam. As the beams rotate (through small angles) on the pin the washers maintain electrical contact and the lead wires flex slightly with the motion. Should the rotary joint fail the damage will be signaled.