Information

This information is part of the Modelica Standard Library maintained by the Modelica Association.

This example demonstrates the functionality of constraint representing universal joint. Each of two bodies is at one of its end connected by spring to the world. The other end is also connected to the world either by universal joint or by appropriate constraint. Therefore, the body can only perform rotation about two revolute axes depending on working forces.

Simulation results

After simulating the model, see the animation of the multibody system and compare movement of body connected by joint (blue colored) with movement of that one connected by constraint (of green color). Additionally, the outputs from sensorConstraintRelative depict position deviations in the constraining element.

animation	Value: true Type: Boolean Description: = true, if animation shall be enabled

Components (13)

	joint	Type: Universal Description: Universal joint (2 degrees-of-freedom, 4 potential states)
	constraint	Type: Universal Description: Universal cut-joint and translational directions may be constrained or released
	sensorConstraintRelative	Type: RelativeSensor Description: Measure relative kinematic quantities between two frame connectors
	bodyOfJoint	Type: BodyShape Description: Rigid body with mass, inertia tensor, different shapes for animation, and two frame connectors (12 potential states)
	bodyOfConstraint	Type: BodyShape Description: Rigid body with mass, inertia tensor, different shapes for animation, and two frame connectors (12 potential states)
	springOfJoint	Type: Spring Description: Linear translational spring with optional mass
	springOfConstraint	Type: Spring Description: Linear translational spring with optional mass
	world	Type: World Description: World coordinate system + gravity field + default animation definition
	fixedRotation	Type: FixedRotation Description: Fixed translation followed by a fixed rotation of frame_b with respect to frame_a
	fixedTranslation	Type: FixedTranslation Description: Fixed translation of frame_b with respect to frame_a
	fixedTranslationOfJoint	Type: FixedTranslation Description: Fixed translation of frame_b with respect to frame_a
	fixedTranslationOfConstraint	Type: FixedTranslation Description: Fixed translation of frame_b with respect to frame_a
	freeMotionScalarInit	Type: FreeMotionScalarInit Description: Free motion joint with scalar initialization and state selection (6 degrees-of-freedom, 12 potential states)

UniversalConstraint

Diagram

Wolfram Language

Information

Parameters (1)

Components (13)