In order to accurately measure the displacement of the head and neck of the dummy under high speed and high acceleration impact conditions

a draw-wire displacement sensor applied to the field of automobile crash test was designed

and experiments on its key performance indexes were carried out.The structure scheme of spiral groove hub and auxiliary convex plate was put forward to reduce the errors of wire rope winding.Thus

the linearity of the draw-wire displacement sensor is less than 0.1 %

and the precision of repeatability is less than 0.02 %.The optimization and performance test of potentiometer and plane coil spring were implemented.Moreover

based on the optimal design of the whole structure

the maximum allowable working speed o

f the draw-wire displacement sensor is greater than 20 m/s

the acceleration is greater than 60 g

n

and the tolerable impact is more than 100 g

n

which generally meet the technical requirements of automobile crash test.