SimMechanics™

Mechanical Branching Bar

Map multiple sensor or actuator lines to one sensor or actuator port on Joint, Constraint, or Driver, or to one Body coordinate system port on Body

Library

Utilities

Description

The Mechanical Branching Bar bundles multiple actuator and sensor connection lines into one line, allowing you to connect multiple actuators and/or sensors to a single connector port on a Joint, Constraint, or Driver, or to a single Body coordinate system (CS) port on a Body. You can choose any number of sensor/actuator ports on the Mechanical Branching Bar.

In the case of a Body, a single Body CS port represents a single Body CS. If the needed Body CS port does not exist, open the Body dialog and create one. You can connect the selected Body CS to multiple Body Actuators and Sensors through the Mechanical Branching Bar.
In the case of a Joint, you need a single sensor/actuator port on the Joint. If the needed port does not exist, open the Joint's dialog and create one. You can connect this sensor/actuator port to multiple Actuators and Sensors through the Mechanical Branching Bar.
Using the Mechanical Branching Bar, you can connect a Joint block to any combination of Joint Sensors, Joint Actuators, Joint Initial Condition Actuators, and Joint Stiction Actuators. The Actuator and Sensor dialogs display the Joint's primitives as if they were directly connected to the Joint.
The procedure for Constraints and Drivers is the same as it is for Joints, except that you need to choose to measure reaction forces/torques or to actuate motions.

Cascading Mechanical Branching Bars and Avoiding Closed Loops

You can connect multiple Mechanical Branching Bar blocks in series, creating a cascade. Connect the mechanical side of the first Branching Bar to a Joint, Constraint, Driver, or Body. Then connect its sensor/actuator side to the mechanical side of the second Branching Bar, and so on.

The only restriction on cascading Mechanical Branching Bars is that you must avoid connecting them into closed loops.

The following diagram shows a cascade, starting at a Body.

Caution To avoid simulation errors, you should not create a cascade of Mechanical Branching Bars that closes on itself in a loop.

You should not connect the mechanical side of one Mechanical Branching Bar to the mechanical side of another Mechanical Branching Bar. You should also not connect the sensor/actuator side of one Mechanical Branching Bar to the sensor/actuator side of another Mechanical Branching Bar.

Dialog Box and Parameters

The dialog has one active area, Connection parameters.

Connection Parameters

Number of branches: Using this spinner menu, you can set the number of extra connector ports needed for connecting Actuator and Sensor blocks to the Mechanical Branching Bar. The default is 2.

Example

Without the Mechanical Branching Bar, you must connect multiple Sensors and Actuators to a Joint by creating a sensor/actuator port on the Joint for each Sensor and each Actuator:

With the Mechanical Branching Bar block, you can combine all the sensor and actuator ports for a single Joint into one sensor/actuator port: