Axis

OptimumK uses three axes to define the coordinates of the suspension points

·         Longitudinal Axis – Points to the forward or backward directions of the car.

·         Lateral Axis – Points to the left or right hand side of the car.

·         Vertical Axis – Points vertically up or down.

The user can define which of the three axes is labeled X, Y and Z. This feature enables easy integration into a CAD package. OptimumK is also able to design a suspension using one reference axis system and then output the results of a simulation using a different reference axis system

Input Reference Axis

Change the input reference axis;

1.     From within the design section select the Options menu button from the Input Toolbar.

2.     Select Referential.

3.     Select the direction of the X, Y and Z axes.

Each design item in a project can have its own individual input reference axis. The input reference axis is exported with a design. When a design is imported back into OptimumK the reference axis will update automatically based on the reference axis that was used when the design was originally exported. 

Upright Reference

All points that are on the upright can be referenced from either the chassis origin (origin used for all other points) or a user defined Upright Origin.

To reference upright points from the Upright Origin;

1.     From within the design section select the Options menu button from the Input Toolbar.

2.     Select Referential.

3.     Un-check the Use Chassis Origin check box.

4.     Enter the Coordinates of the left and right Upright Origins

5.     Enter the Upright Origin Name (e.g. Wheel mounting flange)

All points that are on the upright are now referenced from the Upright Origin. The points that are referenced from the Upright Origin are displayed with red text in the Input Window.

Wheel Reference

The Options in the Referential Window allow the location of the contact patch to be referenced from either the Chassis or Upright Origin. The half track can also be measured from either the contact patch or wheel center.

Simulation Output Reference Axis

Change the output reference axis;

1.     Click the Simulator Preferences button in the Program Toolbar.

2.     Select the Output Tab.

3.     Select the direction of the X, Y and Z axes from within the Referential Axis section.

The selected output reference axis is used for all Simulations in the Analysis section.

Angular Displacement

Positive Roll – Clockwise rotation about the Roll Axis. (When viewed from behind vehicle)

Positive Pitch – Anti-clockwise rotation about the Pitch Axis. (When viewed from left of vehicle)

Positive Yaw – Anti-clockwise rotation around the Center of Gravity. (When viewed from above vehicle)

Motion Sign Convention

Positive Roll – Clockwise rotation about the Roll Axis. (When viewed from behind vehicle)

Positive Pitch – Anti-Clockwise rotation about the Pitch Axis. (When viewed from left of vehicle)

Positive Heave – Vertically up.

Positive Steering – Wheels turn to the Left. (When viewed from above vehicle)