Houdini 20.5 Nodes Dynamics nodes

RBD Car Follow Path dynamics node

Constrain a RBD Car Rig along a path.

Since 20.5

This DOP constrains and aligns an RBD Car Rig along a path while adjusting the constraint geometry’s attributes to match its intended steering and speed and applying a target velocity to the various RBD pieces.

Parameters

Curve

The path to a SOP curve.

Start/End/Inc

When building the path, each point along the path is sampled at every interval defined by Inc between the Start and End frames.

Curve Position

When Path Type is set to Curve, the position along the curve’s U. When the input curve is closed, values of 1 and over will loop. When there are more than 1 input curves, the integer value corresponds to the curve primitive index.

Drift

The amount of drift (back sliding) in corners. This is dependent on the vehicle’s speed and the maximum turning speed along the path.

Overshoot

When drifting, add some overshoot to allow the vehicle to move away from the path.

Respect Vehicle and Turning Maximum Speed

This parameter is available in the DOPs Context. Turn on this option to enforce speed limits on the vehicle, which should result in a more physically plausible simulation while allowing the vehicle to deviate from the animation.

Response Time (ms)

Increasing this value will result in longer braking and acceleration zones, lower maximum turn speeds, while looking further ahead along the path for steering and a lower steering change of rate.

Air Resist

The base air resistance applied to the RBDs to specify how important it is to match the animated position and orientation along the path. Higher values will result in the vehicle matching its target velocity faster. When Respect Vehicle and Turning Maximum Speed is turned on, this will vary depending on whether the vehicle is in an acceleration or braking zone and how far the vehicle is to its target position along the path. Setting this value too high can cause the resulting dynamics to feel unnatural and forced.

Drag

The base drag coefficient applied to the RBDs.

Ground Type

Choose which type of ground collision you want to use.

Position

The center of the ground plane.

Rotation

The orientation of the ground plane.

Height Field

Specify the path to a height field to collide with.

See also

Dynamics nodes