Themechanism used in the assembly is rack andpinion mechanism. It convertsreciprocating motion into rotary motion. Here, therack is the elementproducing reciprocating motion and pinion rotates due tothis reciprocatingmotion. The rack is displaced vertically due to the weight ofthe vehiclepassing on the speed breaker and thus it reciprocates (M. Ramadan,et al,2015). As the rack reciprocates, it turns the pinion to rotate. The rackis theflat part which has teeth, while the pinion is a gear. 

Advantagesof rack and pinion mechanism

a.    This assembly gives good mounting convenience.

b.   Gearlosses are maximum up to 5%.

c.    Approximate efficiency of rack and pinion mechanism is about95%.