Motors control the motion of robot models. You can attach motors to the joints in a robot model. To attach motors to a joint, right-click the joint, and select Set Motors»New from the shortcut menu. When you attach a motor to a joint, the motor ID and motor rate display in the Properties table of the Robot Simulation Model Builder.
You can configure the rate of the motor in the Properties table to control the linear or angular velocity of a joint. The motor rate is the ratio of the motor velocity to the joint velocity as defined by the following equation.
where vj is the joint velocity, rm is the motor rate, and vm is the velocity of the motor that attaches to the joint.
If the joint type is hinge or revolute, the joint velocity is angular velocity. If the joint type is slider or prismatic, the joint velocity is linear velocity. The value of the motor rate can be negative or positive.
The Robot Simulation Model Builder automatically deletes motors that are not attached to any joints. To detach a motor from a joint, select the joint in the Parts Hierarchy list, right-click the joint, and select Set Motors from the shortcut menu. Click the motor that you want to detach.