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Gazebo Apply Command

Send command to Gazebo simulator

Since R2019b

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  • Gazebo Apply Command block

Libraries:
Robotics System Toolbox / Gazebo Co-Simulation

Description

The Apply Command block sends commands to a Gazebo simulation. The block accepts a command message, input as a bus signal, and sends the command to the Gazebo server.

To send command messages, connect to a Gazebo simulation. Open the block mask and click Configure Gazebo network and simulation settings. For more information see Configure Gazebo Simulation.

This block is part of a co-simulation interface between MATLAB® and Gazebo for exchanging data and sending commands. To see a basic example, check Perform Co-Simulation Between Simulink and Gazebo.

Examples

Perform Co-Simulation Between Simulink and Gazebo

Perform Co-Simulation Between Simulink and Gazebo

Set up a synchronized simulation between Simulink™ and Gazebo to send commands and receive data from Gazebo.

Open Live Script
Control Differential Drive Robot in Gazebo with Simulink

Control Differential Drive Robot in Gazebo with Simulink

Control a differential drive robot in Gazebo co-simulation using Simulink®. The robot follows a set of waypoints by reading the pose and wheel encoder positions and generates torque-control commands to drive it.

Open Live Script

Limitations

  • Models that use this block do not support Code Generation or Rapid Accelerator mode.

Ports

Input

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Gazebo command message, specified as a bus. The command is an instruction for a specified model link or joint. Specify the model name as part of the bus signal using the Gazebo Select Entity block.

There are seven different command types with specific fields:

  • ApplyLinkWrench:

    • model_name –– Variable-size uint8 array representing the name of the model in the Gazebo simulator. You can specify this field using the Gazebo Select Entity block.

    • link_name –– Variable-size uint8 array representing the name of the link in the model in the Gazebo simulator. You can specify this field using the Gazebo Select Entity block.

    • force_type –– Variable-size uint8 array specified as 'SET' or 'ADD'. 'SET' overwrites any existing force command for the specified duration. 'ADD' adds the value with existing commands.

    • Fx, fy, fz –– double values specifying the amount of force applied to the Gazebo model link in world coordinates and Newtons.

    • torque_type –– Variable-size uint8 array specified as 'SET' or 'ADD'. 'SET' overwrites any existing torque command for the specified duration. 'ADD' adds the value with existing commands.

    • Tx, ty, tz –– double values specifying the amount of torque applied to the Gazebo model link in world coordinates and Newton-meters.

    • duration –– Bus containing seconds and nanoseconds as double integers, which specify how long to apply the torque in simulation time.

  • ApplyJointTorque:

    • model_name –– Variable-size uint8 array representing the name of the model in the Gazebo simulator. You can specify this field using the Gazebo Select Entity block.

    • joint_name –– Variable-size uint8 array representing the name of the joint in the model in the Gazebo simulator. You can specify this field using the Gazebo Select Entity block.

    • index –– uint32 integer that identifies which joint axis the torque should be applied to.

    • effort –– double scalar value specifying the amount of torque or force to apply to the joint.

    • duration –– Bus containing seconds and nanoseconds as double integers, which specify how long to apply the torque in simulation time.

  • SetLinkWorldPose:

    • model_name –– Variable-size uint8 array representing the name of the model in the Gazebo simulator.

    • link_name –– Variable-size uint8 array representing the name of the link in the model in the Gazebo simulator.

    • world_pose –– Bus containing position and orientation as [x y z] and [x y z w] double vectors, respectively.

    • duration –– Bus containing seconds and nanoseconds as double integers, which specify how long to apply the torque in simulation time.

  • SetLinkLinearVelocity:

    • model_name –– Variable-size uint8 array representing the name of the model in the Gazebo simulator.

    • link_name –– Variable-size uint8 array representing the name of the link in the model in the Gazebo simulator.

    • velocity –– Bus containing linear velocity as [x y z] double vector.

    • duration –– Bus containing seconds and nanoseconds as double integers, which specify how long to apply the torque in simulation time.

  • SetLinkAngularVelocity:

    • model_name –– Variable-size uint8 array representing the name of the model in the Gazebo simulator.

    • link_name –– Variable-size uint8 array representing the name of the link in the model in the Gazebo simulator.

    • velocity –– Bus containing angular velocity as [x y z] double vector.

    • duration –– Bus containing seconds and nanoseconds as double integers, which specify how long to apply the torque in simulation time.

  • SetJointPosition:

    • model_name –– Variable-size uint8 array representing the name of the model in the Gazebo simulator.

    • joint_name –– Variable-size uint8 array representing the name of the joint in the model in the Gazebo simulator.

    • index –– uint32 integer that identifies which joint axis the torque should be applied to.

    • position –– double scalar value representing the joint position.

    • duration –– Bus containing seconds and nanoseconds as double integers, which specify how long to apply the torque in simulation time.

  • SetJointVelocity:

    • model_name –– Variable-size uint8 array representing the name of the model in the Gazebo simulator.

    • joint_name –– Variable-size uint8 array representing the name of the joint in the model in the Gazebo simulator.

    • index –– uint32 integer that identifies which joint axis the torque should be applied to.

    • velocity –– double scalar value representing the joint velocity.

    • duration –– Bus containing seconds and nanoseconds as double integers, which specify how long to apply the torque in simulation time.

    Note

    SetJointVelocity uses the Set Instantaneous Velocity method to set the joint velocity. For more information see, Setting Velocity on Links And Joints.

Note

  • If a duration is 1.005 seconds, it would be 1 second and 5000000 nanoseconds as a bus.

Data Types: bus

Parameters

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Click Select to get a list of command types available in Gazebo. The input Cmd must contain the correct command message structure that matches this type.

Sample time indicates the interval which commands are sent to the Gazebo simulator.

More About

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Version History

Introduced in R2019b

See Also

Blocks

Functions

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