Features

Since it is in plugin style, you can use it without rebuilding MuJoCo from the source.
Plane and cylinder surfaces are supported as sensor mounting surfaces.
Square and hexagonal grids are supported as sensor arrays.
It supports both building with cmake as a standalone project and building with catkin as a ROS package.
If built as a ROS package, sensor information and visualization markers are published as ROS topics.

Install

Requirements

Compiler supporting C++17
Tested on Ubuntu 20.04 / ROS Noetic

Dependencies

MuJoCo (>= 2.3.5)

Installation procedure as a standalone project

$ mkdir ${HOME}/src && cd ${HOME}/src
$ git clone git@github.com:isri-aist/MujocoTactileSensorPlugin.git --recursive
$ cd MujocoTactileSensorPlugin
$ mkdir build && cd build
$ cmake .. -DCMAKE_BUILD_TYPE=RelWithDebInfo -DMUJOCO_ROOT_DIR=<absolute path to MuJoCo>
$ make
$ make install

<absolute path to MuJoCo> is the path to the root directory of MuJoCo. For example, ${HOME}/.mujoco/mujoco-2.3.5 if you installed MuJoCo from release, or ${HOME}/src/mujoco if you installed it from source.

Installation procedure as a ROS package

# Setup catkin workspace.
$ mkdir -p ${HOME}/ros/ws_mujoco/src
$ cd ${HOME}/ros/ws_mujoco
$ wstool init src
$ wstool set -t src isri-aist/MujocoTactileSensorPlugin git@github.com:isri-aist/MujocoTactileSensorPlugin.git --git -y
$ wstool update -t src
# Install dependent packages.
$ source /opt/ros/${ROS_DISTRO}/setup.bash
$ rosdep install -y -r --from-paths src --ignore-src
# Build a package.
$ catkin init
$ catkin config --extend /opt/ros/${ROS_DISTRO}
$ catkin build mujoco_tactile_sensor_plugin -DCMAKE_BUILD_TYPE=RelWithDebInfo -DMUJOCO_ROOT_DIR=<absolute path to MuJoCo>

Add source ${HOME}/ros/ws_mujoco/devel/setup.bash to ${HOME}/.bashrc.

Examples

Example as a standalone project

Assume that MuJoCo is installed in ${HOME}/.mujoco/mujoco-2.3.5 from release, and MuJocoTactileSensorPlugin is cloned under ${HOME}/src/.

$ cp ${HOME}/src/MujocoTactileSensorPlugin/build/src/libTactileSensorPlugin.so ${HOME}/.mujoco/mujoco-2.3.5/bin/mujoco_plugin
$ cd ${HOME}/.mujoco/mujoco-2.3.5/bin
$ ./simulate ${HOME}/src/MujocoTactileSensorPlugin/xml/sample_tactile_sensor.xml

Example as a ROS package

Assume that MuJoCo is installed in ${HOME}/.mujoco/mujoco-2.3.5 from release, and the path to the catkin workspace is ${HOME}/ros/ws_mujoco.

# Terminal 1
$ cp ${HOME}/ros/ws_mujoco/devel/lib/libTactileSensorPlugin.so ${HOME}/.mujoco/mujoco-2.3.5/bin/mujoco_plugin
$ cd ${HOME}/.mujoco/mujoco-2.3.5/bin
$ ./simulate `rospack find mujoco_tactile_sensor_plugin`/xml/sample_tactile_sensor_ros.xml
# Terminal 2
$ roslaunch mujoco_tactile_sensor_plugin display.launch

Plugins

MujocoTactileSensorPlugin

This is a ROS-independent plugin to simulate tactile sensors.

The following attributes are required.

sensor_nums: Number of sensors in each of the X and Y directions in a 2D array
sensor_interval: Interval between adjacent sensors [m]
surface_radius: Radius of the sensor mounting surface (zero for plane, positive for cylinder)
is_hex_grid: Whether the sensor grid is square or hexagonal (true for hexagonal, false for square)

An example of tags to be added to the MJCF file:

<extension>
  <plugin plugin="MujocoTactileSensorPlugin"/>
</extension>
<sensor>
  <plugin name="tactile_sensor" plugin="MujocoTactileSensorPlugin" objtype="site" objname="[site name]">
    <config key="sensor_nums" value="20 20"/>
    <config key="sensor_interval" value="0.02"/>
    <config key="surface_radius" value="0.5"/>
    <config key="is_hex_grid" value="true"/>
  </plugin>
</sensor>

MujocoTactileSensorRosPlugin

This is a plugin with ROS interface to simulate tactile sensors. This is only available when built as a ROS package.

In addition to the attributes of MujocoTactileSensorPlugin, the following attributes are required.

frame_id: Frame ID of ROS topic (Site name is used if omitted)
topic_name: ROS topic name of sensor data
publish_rate: Period to publish the topic of sensor data [Hz]

An example of tags to be added to the MJCF file:

<extension>
  <plugin plugin="MujocoTactileSensorRosPlugin"/>
</extension>
<sensor>
  <plugin name="tactile_sensor" plugin="MujocoTactileSensorRosPlugin" objtype="site" objname="[site name]">
    <config key="sensor_nums" value="20 20"/>
    <config key="sensor_interval" value="0.02"/>
    <config key="surface_radius" value="0.5"/>
    <config key="is_hex_grid" value="true"/>
    <config key="topic_name" value="/mujoco/tactile_sensor"/>
    <config key="publish_rate" value="10"/>
  </plugin>
</sensor>