Body Constraints

You can simulate a body sliding on a plane without modeling the plane itself or explicitly defining the contact forces between the moving body and the plane.

The contact constraint can be used to model resting or sliding contact between one or more bodies and a half-plane. Both static and dynamic friction are accounted for. Contact can be broken, but colliding contact is not supported.

For more details, refer to [contact constraint] Properties.

You can use the driver to prescribe the velocity of one point on one 6-DOF body relative to a second point on another 6-DOF body in a given, user-specified direction. You can also prescribe the velocity of a point on a single body relative to a fixed point in the environment, for example, the origin of the Laboratory coordinate system.

Typical examples are ship propulsion and tube launch applications. For ship propulsion, a typical situation would be to prescribe a fixed velocity in the ship forward direction, while a rudder with changing positions/angles provides the yawing motions.

For more details, see [velocity driver] Properties.

A typical application is an excavator. In the example below, you define the arms of the excavator as mechanical bodies, since their interaction with fluid flow can be neglected. The ladle of the excavator is defined as a continuum body, which can interact with fluid flow or DEM. To control the motion of the excavator, you constrain these bodies using distance drivers. In the following image, the distance drivers are represented by orange bars.

For more details, see [distance driver] Properties.