Controlling the Suspension
Getting the vehicles to rest properly on the ground is hard.
Recommended settings:
Length should be whatever distance from wheel center to maximum shock compression.
Stiffness: ~500
Damping Relaxation: ~500
Damping Compression: 1.0
Max Travel: ~30
Max Force: ~100
Wheel Axes
Rotation Axis is the axis around which the wheel spins.
All wheels should be aligned the same as the Front Left wheel.
If X+ is pointing OUT of the Front Left wheel, then the Rotation Axis is X+
Suspension Axis is the direction the vehicle travels (e.g. forward relative to the vehicle body).
So if the Y+ axis points out the front of the vehicle, then the Suspension Axis is Y+
Vehicle Hierarchy
Remember when creating vehicles for BT Vehicle that the wheels must be linked to the body in a SPECIFIC ORDER!
Front Left
Front Right
Rear Left
Rear Right
These notes are rather old...
1. To create the car, create the body geo and link some wheels to it.
wheel order matters: front left, front right, back left, back right
2. Create a particle group called car (or whatever, this is to hold the top-level entity of the vehicle), and create sub-groups for body and wheels
3. Create an SC collision operator
4. Born the body particles with any basic generator method (PosBorn, MW, Draw, etc)
be careful if trying Obj2Particle that it might upset the orientation
5. Create the first Vehicle operator and use the body as the Particle input
of course be sure to set the "Collision" parameter at the top of the operator to the Collision operator in your tree
setup the initial Vehicle properties (dampening, axes, etc)
6. Create the second Vehicle operator
tell it to use the same Collision operator
create a body particle input
assign the same G Body and G Wheel settings as the first Vehicle operator
control the Speed and Steering and other inputs with this second Vehicle operator
Note: the original mesh transform may affect the alignment of the top-level "car" group -- use Set Alignment to handle any corrections (on birth only).
Note: Spin may screw up the wheels and cause them to spin around the body
Note: Dampers (or shocks) are straight
Damper Height is the height between the body and the wheel center
Damper Spring: is the spring constant (hardness)
Spring Damper: is the dampening progressiveness or friction so it stops springing
Spring Damper=0 means it swings forever