Watt’s mechanism is a crossed four bar chain mechanism and was used by Watt for his early steam engines to guide the piston rod in a cylinder to have an approximate straight line motion.

Maximum velocity is determined at 00 ,1800 and 3600.

None.

It can be used in all positions.

Ackermann steering gear fulfils the condition of correct steering at only three positions.

Though the gear is theoretically correct, but due to the presence of more sliding members, the wear will be increased which produces slackness between the sliding surfaces, thus eliminating the original accuracy. Hence Davis steering gear is not in common use.

Maximum speed of the driven shaft,

Hart’s mechanism requires only six links as compared with the eight links required by the Peaucellier mechanism.

Hooke’s joint is used to connect two shafts, which are intersecting at a small angle.

In a pantograph, all the pairs are turning pairs. It has 4 links.