Joint dynamics properties
The joint dynamics properties are part of the joint properties. Its dialog displays the dynamics settings and parameters of the last selected joint. If no object is selected, the dialog is inactive. If more than one joint is selected, then some parameters can be copied from the last selected joint to the other selected joints (Apply to selection-buttons. Be aware that this however only has an effect between joints of same type or mode):
[Joint dynamics dialog]
Motor enabled: enables or disables the motor of the joint. If disabled, the joint is free. Available only if the joint is in torque/force mode.
Target velocity: the target velocity for the joint motor. The target velocity will be instantaneously reached if the maximum torque/force is high enough; otherwise the target velocity is gradually approached. Available only if the joint is in torque/force mode.
Engine specific properties: allows adjusting engine-specific parameters. Refer to the dynamics engines properties dialog related to joints.
Max. torque/force: the torque or force at which the joint motor operates. Available only if the joint is in torque/force mode, or in hybrid operation mode.
Control loop enabled: enables or disables the joint control loop. By default, a built-in PID controller is used (see further down). This item is available only if the joint is in torque/force mode.
Custom control: if enabled, then the joint will be controlled via a joint control callback script. This allows the user to write very specific joint controllers, that will be executed at each physics engine simulation step (i.e. by default 10 times more often than the simulation time step).
Edit custom control loop: allows editing the joint control callback script for a custom joint control.
Position control (PID): enables or disables the default PID joint control loop.
Regulate velocity: the PID controller will adjust the joint velocity (refer to the section on joint types and operation for details). Upper limit allows limiting the regulation velocity to a maximum value.
Regulate torque/force: the PID controller will modulate the joint torque/force (refer to the section on joint types and operation for details)
Proportional / Integral / Derivative parameter: the P / I / D parameter of the PID position control.
Joint types and operation
Dynamics engines properties related to joints