Gazebo ros_control Interfaces

This is a ROS package for integrating the ros_control controller architecture with the Gazebo simulator.

This package provides a Gazebo plugin which instantiates a ros_control controller manager and connects it to a Gazebo model.

It extends the default plugin available in gazebo_ros_control.
This plugin has originally been discussed and proposed here.

Besides the features provided by the default

``` plugin, this plugin here adds the following additional features:
 - Support for HardwareInterface-Switching
 - Enable joint filtering

__NOTE__: The control\_methods 
```POSITION_PID
``` and 
```VELOCITY_PID
``` are not supported anymore, i.e. PID parameters loaded to the parameter server under namespace 
```/gazebo_ros_control/pid_gains/
``` are ignored. In case you want to command e.g. positions but want to write efforts to Gazebo, use the 
```effort_controllers/JointPositionController
``` (or similar) and set your PID values thers. 

--- 
 
## Usage

[Documentation](http://gazebosim.org/tutorials?tut=ros_control&cat=connect_ros) related to the default plugin is provided on Gazebo's website.

To use the plugin, add the following to your robot's URDF:

The 
```robotNamespace
``` is used as a prefix for the 
```controller_manager
``` instantiated by the plugin.  
The tag is optional and will default to global namespace '/' if not set.  
In the example above the services will be advertised under 
```/NAMESPACE/controller_manager
```.  
__NOTE__: Do not use a trailing '/' before NAMESPACE!

You can also use the tags 
```robotParam
``` and 
```controlPeriod
``` as for the default plugin.

The tag 
```robotSimType
``` is ignored and defaults to 
```cob_gazebo_ros_control/HWISwitchRobotHWSim
``` which is a specialized HardwareInterface which is also provided in this package. 
```HWISwitchRobotHWSim
``` derives from 
```DefaultRobotHWSim
``` of the default plugin.  

#### Support for HardwareInterface-Switching

With this plugin, you can now specify multiple HardwareInterfaces for the transmissions of your joints, like this:  

<transmission name="arm_1_trans">
  <type>transmission_interface/SimpleTransmission</type>
  <joint name="arm_1_joint">
    <hardwareInterface>hardware_interface/PositionJointInterface</hardwareInterface>
    <hardwareInterface>hardware_interface/VelocityJointInterface</hardwareInterface>
  </joint>
  <actuator name="arm_1_motor">
    <mechanicalReduction>1</mechanicalReduction>
  </actuator>
</transmission>

You can specify any HardwareInterface out of [
```PositionJointInterface
```, 
```VelocityJointInterface
```, 
```EffortJointInterface
```]. The order of does not matter.  

#### Enable joint filtering

The default 
```gazebo_ros_control
``` plugin creates JointHandles for all the joints present in your URDF. In order to only assign a specific set of joints to one plugin - and then use several plugins under different 
```robotNamespaces
``` - you can use the new tag 
```filterJointsParam
```.

The plugin will only create JointHandles given in the list loaded to the parameter server under 
```/NAMESPACE/joint_names
```. In case the parameter cannot be found, the plugin fails to load.

The 
```joint_names
``` parameter might look like this:  

```joint_names: [arm_1_joint, arm_2_joint, arm_3_joint, arm_4_joint, arm_5_joint, arm_6_joint, arm_7_joint]

Benefit

This plugin allows to use ros_controllers requiring different HardwareInterfaces within the same gazebo session.
(No need to change the URDF for a different control_mode).

For example:

#position controller
arm_1_joint_position_controller:
  type: position_controllers/JointPositionController
  joint: arm_1_joint

#velocity controller
arm_1_joint_velocity_controller:
  type: velocity_controllers/JointVelocityController
  joint: arm_1_joint

can be loaded to the parameter server (under the NAMESPACE of the controller_manager) and then those two controllers can be switched using the ControllerManagers switch_controller -Service “on-the-fly”.

A side-benefit of this is that no “PID-Parameter-Tuning” would be required for simulation anymore, as gazebo supports all the (Standard-)HardwareInterfaces.

Changelog for package cob_gazebo_ros_control

0.7.8 (2024-02-19)

0.7.7 (2022-07-29)

0.7.6 (2021-12-23)

0.7.5 (2020-09-26)

• Merge pull request #47 from fmessmer/test_noetic test noetic
• Bump CMake version to avoid CMP0048 warning
• Merge pull request #44 from MatthiasNieuwenhuisen/fix_joint_filtering_segfault Fix wrong array index occuring if using joint filtering
• Fix wrong array index occuring if using joint filtering
• Contributors: Felix Messmer, Matthias Nieuwenhuisen, fmessmer

0.7.4 (2020-03-18)

• Merge pull request #41 from fmessmer/ci_updates [travis] ci updates
• catkin_lint fixes
• Merge pull request #40 from fmessmer/fix_warnings fix catkin_package DEPENDS warning
• fix catkin_package DEPENDS warning
• Contributors: Felix Messmer, fmessmer

0.7.3 (2019-08-06)

• Merge pull request #38 from benmaidel/melodic-devel [Melodic]
• backwards compatibility wrt hardware interface prefix
• query physics engine type
• remove obsolete member variable
• adjust plugin readme
• fix get simulation time for older gazebo version
• fix interface_type inference
• joint_interface should have prefix 'hardware_interface'
• fix compilation error
• Contributors: Benjamin Maidel, Felix Messmer, Shohei Fujii, fmessmer

0.7.2 (2018-01-07)

• Merge pull request #34 from ipa320/kinetic_release_candidate Kinetic release candidate
• Merge pull request #32 from ipa-fxm/kinetic_dev [kinetic] updates from indigo_dev
• Merge branch 'indigo_dev' of github.com:ipa320/cob_gazebo_plugins into kinetic_dev Conflicts: .travis.yml
• Merge pull request #31 from ipa-fxm/update_maintainer update maintainer
• update maintainer
• Merge pull request #28 from ipa-fxm/APACHE_license use license apache 2.0
• use license apache 2.0
• Contributors: Felix Messmer, ipa-fxm, ipa-uhr-mk

0.7.1 (2017-07-17)

• fix dependencies
• Contributors: Richard Bormann

0.7.0 (2017-07-17)

• Merge branch 'indigo_dev' of github.com:ipa320/cob_gazebo_plugins into multi_distro_travis_kinetic Conflicts: .travis.yml README.md
• compile with c++11
• Kinetic and Gazebo > 2, fixed hardware_interface::ControllerInfo API change
• Contributors: Benjamin Maidel, Dinesh Thakur, ipa-fxm

0.6.6 (2017-07-17)

• add state_valid behavior
• add estop behavior
• manually fix changelog
• Contributors: ipa-fxm

0.6.5 (2016-10-10)

0.6.4 (2016-04-01)

0.6.3 (2015-08-25)

• boost revision
• remove trailing whitespaces
• migration to package format 2
• fix missing dependency
• review dependencies
• Contributors: ipa-fxm

0.6.2 (2015-06-17)

• using strict_hwi_switch api
• more suitable name for plugin
• beautify CMakeLists
• use hwi_switch api
• proper reset of joint limit interface
• cleanup output
• Contributors: ipa-fxm

0.6.1 (2014-12-12)

• Update README.md
• Update README.md
• Update README.md
• Update README.md
• Update README.md
• enable joint filtering for multi_hwi_gazebo plugin
• remove support for X_PID control_methods for simplicity (obsolete anyway)
• unify ROS STREAM output
• ignore 'robotSimType'
• Update README.md
• Update README.md
• add README for new plugin
• correctly reset all interfaces in doSwitchHWInterface
• new gazebo_ros_control_plugin supporting multiple hardwareinterfaces and switch on controller_switching
• Contributors: Felix Messmer, ipa-fxm