Testbed Software Installation

Software installation for the testbed

Install the ROS software

These instructions assume you have at least a basic ROS install, C/C++ compilers, etc

Get prerequisities:

apt install -y python3-vcstool

On a system running ROS Noetic, create a ROS workspace and checkout out testbed_hw:

mkdir -p testbed_ws/src
cd testbed_ws/src
git clone https://gitlab.com/rsa-manipulation-testbed/testbed_hw

Then checkout the other dependencies using the .rosinstall file found in that repo, then use rosdep to get any other dependencies

cd ..
vcs import testbed_hw/testbed_hw.rosinstall
rosdep install --ignore-src --from-paths . -y

Then build:

catkin build

Install the Clearpath Device Driver

The Clearpath communication hub requires a special device driver. This must be built and installed manually any time the system kernel is updated. If the driver is not installed, the system hub will show up as a /tty/devACMx device. If installed properly, the hub will show up as a /dev/ttyXRUSBx device.

A short script install_kernel_modules.sh is included in testbed_hw/clearpath_sc_ros which will automate this building process. It can be run from a checkout of tha repo or:

wget -O - https://gitlab.com/rsa-manipulation-testbed/testbed_hw/-/raw/main/clearpath_sc_ros/install_kernel_module.sh | /bin/bash -

Configuration

Most system configuration is centralized in the testbed_sw repository. This repo contains multiple sub-packages:

testbed_config contains testbed hardware and controller configurations.
testbed_description/ contains the URDF and meshes for the testbed.
testbed_moveit_config/ contains configuration for MoveIt! and Gazebo for the testbed.

Most of the configuration should be set to appropriate default values, with the exception of the Clearpath motor mapping, which must be set for each Testbed site.

Motor mapping

The software must be told explicitly which Clearpath motors correspond to which testbed axes. This is done through a config file in testbed_config called {TESTBED_SITE}_config.yaml where {TESTBED_SITE} is a descriptive name for a given testbed installation.

The file contains four config params which give the Clearpath serial number fo the for axis. For example uwapl_config.yaml is:

#
# Clearpath motor serial number for APL Testbed
#
yaw_sn: 70403992
zaxis_sn: 73003302
corexy_a_sn: 65800963
corexy_b_sn: 66102023

The testbed.launch assumes that the argument testbed_site is set, or as a default will look for an environment variable TESTBED_SITE

!!! We strongly suggest that the environment variable TESTBED_SITE be set automatically on the user account/computer which drives the testbed.

Clearpath motor configuration

The clearpath_config.yaml file sets motor paramters within the Clearpath motor itself. This includes velocity, acceleration, current and jerk limits. As these limits are set in the motors they are absolute limits on motor performance.

ROS Controller configuration and tuning

The testbed_controllers.yaml file describes the motor control interfaces exposed by the Testbed to the ROS Control system. Since the testbed uses position control loops which run within ROS this includes PID parameters for those control loops, as well as joint limits to be enforced by the software controllers.