Kinematic Synthesis of a Crossed Four-Bar Mechanism for Automotive Steering

Kinematic synthesis has been carried out for crossed four-bar mechanisms to be used in steering mechanism of four wheel vehicles with several values of track to wheelbase ratios. Two equal spur gears have been included in the mechanism. Initial estimate has been made for the link size and angular orientation for straight ahead motion using iterative techniques. Hooke and Jeeves optimization method has been used to carry out the final estimation of the two design parameters. The objective function comprises of the steering errors only. Five precision points have been found out in the entire range of rotation of the front wheels. A very low steering error has been achieved by the kinematic synthesis. The limitation of this mechanism has been discussed and suitable modification has been suggested.