Standard joints properties

Enter joint properties for an existing standard joint.

Access:

In the Dynamic Simulation browser, right-click a standard joint and select Properties.

General tab

These parameters define joint vectors in the graphics window. The vectors are expressed in the joint coordinate system . If you insert the joint manually, the joint coordinate system is the joint coordinate system of the first components selected for joint insertion.

Suppress joint	Suppresses the joint so that it is not considered in subsequent simulations . By default, the joint is active.
Lock DOFs	Locks all degrees of freedom in the joint. Locked degrees of freedom do not move during simulation.
Type	Displays the joint type. You cannot change this value.
Display	Displays force and torque vectors in the graphics window. When you select the joint in the browser, the joint coordinate system appears in blue in the graphics window. Force shows the force vector. Torque shows the torque vector. Scale adjusts the size of the vector in the graphics window. Use this option to make all of the vector visible. The default is 0.01. Color opens the Microsoft Color dialog box so that you can select a color for the vector.

DOF tabs

These tabs contain parameters for specific degrees of freedom. The title of each tab is "DOF," a number identifying the degree of freedom, and either R for rotational or T for translational. Icons show parameters for initial positions, forces or moments, and imposed motions.

DOF (T) and DOF (R) positions

	Displays the initial conditions for this translational or rotational degree of freedom.
Position	Sets the initial position for this degree of freedom.
Locked	Locks this degree of freedom in this position.
Velocity	Sets the initial velocity of this degree of freedom.
Computed	Indicates that the software automatically computes the initial velocity, taking into account the physical environment. We recommend selecting this option. To impose a velocity, use Impose motion. Clicking this box disables the automatic computation of the initial velocity by the software.
Bounds	Sets the minimum or maximum values for this degree of freedom. Because these bounds are elastic, define the stiffness and damping of the bounds. If the position of this degree of freedom becomes lower than the minimum boundary or higher than the maximum boundary, the software automatically applies a reaction force proportional to the distance the position is beyond the bound.
The text boxes in the following group give you the option of entering a constant value or a value that varies during simulation. Clicking opens a menu that gives you the choice of Constant value or Input grapher. Constant value is the default. If you select Constant value, you can enter the value in the text box. If you select Input grapher, appears in the text box. Clicking this icon opens the Input Grapher, which you use to define values that vary during simulation.
Min.	Enables the Value, Stiffness, and Damping boxes so that you can enter the minimum values. Value sets the minimum boundary for this force or torque. Stiffness sets the stiffness of the minimum boundary. Damping sets the damping of the minimum boundary.
Max.	Enables the Value, Stiffness, and Damping boxes so that you can enter the maximum values. Value sets the maximum boundary for this force or torque. Stiffness sets the stiffness of the maximum boundary. Damping sets the damping of the maximum boundary.

DOF (T) forces and DOF (R) torques

	Displays parameters that define the action/reaction force for this translational degree of freedom (DOF).
	Displays parameters that define the action/reaction torque for this rotational degree of freedom.
Enable joint force or Enable joint torque	Activates the joint force or torque and enables the parameters in this dialog box.
These text boxes all give you the option of entering a constant value or a value that varies over time. Clicking opens a menu that gives you the choice of Constant value or Input grapher. Constant value is the default. If Constant value is the selection, you can enter the value in the text box. If Input grapher is the selection, appears in the text box. Clicking this icon opens the Input grapher, which you use to define values that vary during simulation.
Value	Sets the value of the force or torque.
Damping	Sets viscous damping. The action/reaction force or torque applied is proportional to the velocity of the degree of freedom.
Spring	Sets parameters for springs. Free position indicates the position of the spring (if either linear or spiral) when force is zero. This position corresponds to the free length of a spring joint. Elastic stiffness sets the elastic stiffness (either translational or rotational) of the spring.
Dry friction	Sets parameters for friction . Coefficient is the value of the dry friction coefficient. This coefficient can vary between 0 and 2. Radius is available only for Edit joint torque Radius sets the radius of the rotational axis. To calculate the equivalent action/reaction torque due to friction, the software multiplies this value by the friction force.

DOF (T) and DOF (R) Motions

	Displays Edit imposed motion parameters for this translational or rotational degree of freedom.
Enable imposed motion	Activates the joint imposed motion and enables the parameters in this dialog box.
Driving	Defines the driving motion. Position indicates that you are imposing a position as a function of time. Velocity indicates that you are imposing a velocity as a function of time. Acceleration indicates that you are imposing an acceleration as a function of time.
The next text box gives you the option of entering a constant value or a value that varies over time. Clicking opens a menu that gives you the choice of Constant value or Input grapher. Input grapher is the default. If you choose Constant value, you can enter the value in the text box. If you choose Input grapher, appears in the text box. Clicking this icon opens the Input grapher, which you use to define values that vary over time.
Value	Sets the value for the driving motion.