Control engineering

Everyday German has a phrase for the whole subject of this list: übers Ziel hinausschießen, literally to shoot past the target. It is said of a ministry whose new rule goes further than the problem, or of a parent whose punishment outweighs the offence, and it describes precisely what a controller does when it is tuned too hard. It sees an error, answers with more force than the error needs, lands on the far side of the setpoint and has to correct back — and a loop that keeps correcting its own corrections has turned into an oscillator. Engineers keep the picture and only swap the verb, from shooting to swinging: das Überschwingen. The cure is the same in both registers, which is to look ahead before correcting, and in a controller that look-ahead has a name of its own: der Vorhalt.