Adams Assignments – Problem 4 – Steering geometry 2

The default hrdpoints can be seen in the image below.

The caster angle, caster moment arm, kingpin inclination angle, steer axis offset(resultant), steer axis(longitudinal offset) and scrub radius for the above hardpoints can be seen below.

Caster angle = 5.369 degree

Caster moment arm = 9.7967mm

kingpin inclination = 10.0855 degree

steer axis offset(resultant) = 85.7745

steering axis offset(longitudinal) = 17.61mm

scrub radius = 33.8081mm

For this problem, we can divide the sub questions based on the front view geometry and side view geometry. We can then optimize the front view geometry (Y and Z axis) to achieve the required targets of kingpin inclination, scrub radius and steering axis offset(resultant). Tuning hardpoints(ball joints) in Y axis can yield us the front view geometry targets. Next we move on to side view geometry(X and Z axis) which has influence on caster angle, caster moment arm and steer axis offset(longitudinal).

The modified hardpoints can be seen below.

After Modification

Front view of optimized Hardpoints

Side view of optimized Hardpoints

Targets

caster angle = 3.96 degree

caster moment arm = 20.1725mm

kingpin inclination angle = 13.0981 degree

steer axis offset(resultant) = 82.2871mm

steer axis offset(longitudinal) = 0mm

scrub radius = 19.0961mm

No all the parameter cannot be controlled independtly. For Example- if we change the parameter of UCA ball joint in front view, it will definitely have an influence on scrub radius and Kingpin inclination angle.