I used to work on error proofing software at an automotive assembly plant, and it turns out that error proofing steering wheel torque is hard. Error proofing m

I used to work on error proofing software at an automotive assembly plant, and it turns out that error proofing steering wheel torque is hard. Error proofing means at least two things in this context: 1. Making the operation hard to fail at, aka poka yoke (mistake proofing), sometimes called idiot proofing. 2. Work specification validation. Both of these are difficult because the steering column has to be immobilized and then it has to be re-mobilized. This is not hard, per se, but it is just slightly more complicated than other assembly steps. How does this happen? The validation mechanism and operator both have a type 2 error (false negative, failure to detect a fault) - they are not aware that some part of the tooling is not working or sensing correctly. Other things that can cause this: manual intervention to release a vehicle from the work cell due to excessive type 1 errors (false positive errors); repair work after the vehicle leaves the assembly line; off by one errors in vehicle tracking.