This specifications.md file is a description and proof of virtual model validation for the CERBERUS ANYmal B with Sensor Configuration 1. This robot may be launched using a ign launch command with the variable name cerberus_anymal_b_sensor_config_1.
ANYmal is a highly sophisticated four-legged robot, designed to tackle the challenges of harsh search and rescue operations, inspections, and other surveillance duties. In this configuration ANYmal is equipped with the following sensors: LIDAR, downward facing depth camera, forward facing color camera, two color cameras on the sides, and an IMU.
To be able to control this robot model you need a few additional packages. Please clone the repository cerberus_anymal_locomotion and follow the instructions specified in its Readme.
The vehicle can be launched with the following command:
ign launch -v 4 competition.ign robotName1:=anymal_b robotConfig1:=CERBERUS_ANYMAL_B_SENSOR_CONFIG_1
In another terminal you can source the "anymal_locomotion_ws" workspace (see Dependencies) to start the locomotion controller node:
cd ~/anymal_locomotion_ws/
source devel/setup.bash
roslaunch cerberus_anymal_b_control_1 cerberus_anymal_controller.launch
At this point you can control the vehicle model with a twist command, for example:
rostopic pub /anymal_b/cmd_vel geometry_msgs/Twist "linear:
x: 0.5
y: 0.0
z: 0.0
angular:
x: 0.0
y: 0.0
z: 0.0"
Note that the vehicle moves with a constant forward and angular velocity. This is a design choice and cannot be changed. Therefore the input twist is used only to determine in which direction the vehicle should move. See Control for more information.
The software included in this package is released under a BSD 3-Clause license.
ANYmal model is adapted from anymal_b_simple_description repository, released under BSD 3-Clause license.
The CERBERUS ANYmal robot is a research platform and its cost is not publicly available at the moment. It weighs approximately 37 kg.
This ANYmal with sensor configuration 1 includes the following sensors. The specifications for these instruments are provided below in the Validation Links section.
- IMU - Xsens MTi 100, modeled by
imuplugin - LIDAR - Velodyne VLP-16, modeled by
gpu_lidarplugin - LIDAR - Robosense RS-Bpearl, there is not (yet) an Ignition-Gazebo plugin
- Depth Camera - Intel Realsense D435, modeled by
rgbd_cameraplugin - Color Camera - FLIR Blackfly S Model ##BFS-U3-16S2C-CS , modeled by
cameraplugin - Synchronization Board - Autonomous Systems Lab, ETH Zurich - VersaVIS, there is not (yet) an Ignition-Gazebo plugin
- 12 communication breadcrumbs are also available as a payload for this robot in sensor configuration 2.
This ANYmal is controlled by the custom cerberus_anymal_b_control_1 package, available in the repository cerberus_anymal_locomotion.
This controller makes the robot moving at a fixed velocity, in any direction. The input twist is used only to determine the orientation of movement. The bearing angle between X-axis and the orientation specified by the linear part of the twist vector indicates the direction of motion; The positive or negative value of the yaw rate of the twist vector sets the direction of rotation around the Z-axis.
Based on the tests specified in the DARPA SubT Challenge Model Preparation Guide, this vehicle has the following motion constraint characteristics.
- x velocity range from -0.45 m/s to 0.45 m/s
- y velocity range from -0.45 m/s to 0.45 m/s
- z velocity range from 0 m/s to 0 m/s
- x acceleration range from -0.024 m/(ss) to 0.024 m/(ss)
- y acceleration range from -0.024 m/(ss) to 0.024 m/(ss)
- z acceleration range from 0 m/(ss) to 0 m/(ss)
- Turning radius of 0 m (can rotate on the spot)
Based on the tests specified in the DARPA SubT Challenge, this vehicle has the following endurance characteristics.
- Battery life of 4200 seconds
The following points highlight the differences between the submitted virtual model and its hardware counterpart.
-
Robosense RS-Bpearl LIDAR is not present in simulation since its Ignition-Gazebo plugin does not exist yet. A downward Intel Realsense is used as a replacement in simulation.
-
VersaVIS board is used to time synchronize a camera with an IMU for Visual-Inertial Odometry purposes. At the moment there is no plan to develop an Ignition-Gazebo plugin for that and therefore this board is not included in simulation.
-
The physical robot carries 4 communication breadcrumbs. 12 breadcrumbs are included in sensor configuration 2, which is standardized to match other available models.