Virtual Caster and Kingpin Inclination
Branch ID: 330 Request Number: 50000330
The kingpin axis on an SLA or Macpherson strut suspension is defined by two points (the upper ball joint and the lower ball joint in the SLA suspension, the upper strut mount location and the lower ball joint in the case of the Macpherson strut suspension) When the kingpin axis is not defined by two distinct points, it must be calculated virtually, using the motion of the spindle to calculate the instant axis of rotation of the knuckle. The virtual requests (numbers 50000310-50000350) use this method to calculate the kingpin location, and parameters that rely on the kingpin location. These requests should be used on suspensions that do not have a clearly defined kingpin axis, such as a 4 link or 5 link front independent suspension.
| Component | Unit | Comment |
|---|---|---|
| 1 (X): Left Virtual Caster Angle | deg | The magnitude is the global side view angle between the left virtual kingpin axis and global vertical. The sign is positive when the kingpin axis goes towards the front of the vehicle at the bottom and towards the rear of the vehicle at the top. |
| 2 (Y): Right Virtual Caster Angle | deg | The magnitude is the global side view angle between the right virtual kingpin axis and global vertical. The sign is positive when the kingpin axis goes towards the front of the vehicle at the bottom and towards the rear of the vehicle at the top. |
| 3 (Z): Average Virtual Caster Angle | deg | The mean of components 1 and 2. |
| 4 (RX): Left Virtual Kingpin Inclination Angle | deg | The magnitude is the global front view angle between the left virtual kingpin axis and global vertical. The sign is positive when the kingpin axis goes outboard at the bottom and inboard at the top. |
| 5 (RY): Right Virtual Kingpin Inclination Angle | deg | The magnitude is the global front view angle between the right virtual kingpin axis and global vertical. The sign is positive when the kingpin axis goes outboard at the bottom and inboard at the top. |
| 6 (RZ): Average Virtual Kingpin Inclination Angle | deg | The mean of components 4 and 5 |