[Collada Physics] Motors

Other Standards COLLADA
1

After reading Collada Physics specifications, I’ve understood that force_fields can be used to represent motors, since motor apply a force in some way. (Correct me if I’m wrong)

Specification also states that currently there is not predefined way to describe a technique.

So, my question is (if above is all true): “Has anyone defined their custom force fields? And if so, could you share your xml approach?”

I’m particularly interested in such motors as:
[ul]
Attractor motors (provide gravitational attraction between two objects)
Geared motors (simplified automobile engines)
Servo motors (achieve a desired angle or velocity)
Spring motors
Thruster motors (provide a constant force on an object)
Velocity motors (use force to achieve desired velocity)
[/ul]

I’d imagine that this has already been addressed by various exporters and importers for 3dsmax, ageia, etc., as I have seen videos running various physical simulations that would require some form of force_fields. For example, some videos were showing car simulation, which would require creating some motor to drive and steer the car.

Thanks in advance.

2

Force fields are meant to mimic the functionality of the same name in Maya and in Softimage. I don’t know if 3DSMax has the same concept. It basically exerts a force on a rigid body, e.g. a gravity, or an attraction/repulsion field, etc. For an example, see this movie:

http://www.feelingsoftware.com/Files/Ni … nField.avi

Regarding motors… I’m only familiar with the PhysX joint motors. In PhysX, the rigid constraints (called joints) have parameters that can be used to drive a position (linear or angular) or velocity (linear or angular). Therefore this could be stored in a rigid constraint-specific <extra> or <technique>. We haven’t attempted to standardize these features in COLLADA yet.

I hope this helps a bit.