bosch_locator_bridge

ROS interface to Rexroth ROKIT Locator

README

General information about this repository, including legal information and build instructions are given in README.md in the repository root.

bosch_locator_bridge

Overview

This package provides a ROS 2 interface to the Rexroth ROKIT Locator. It translates ROS 2 messages to the ROKIT Locator API (as described in the ROKIT Locator API documentation) and vice versa. It also allows to control the ROKIT Locator via ROS 2 service calls.

The package has been tested under ROS 2 Humble and Ubuntu 22.04. The bridge is compatible with ROKIT Locator version 1.10. If you have an earlier version, see Support of earlier versions of ROKIT Locator.

Quick Start

This section describes how to record your environment, create a map out of the record and localize yourself within it.

Ensure the ROKIT Locator is reachable from your computer

Make sure the ROKIT Locator is installed and running on a computer in your network. You can test this by running the following command in a terminal (replace <LOCATOR_IP> by the IP address of the computer running the ROKIT Locator):

curl --header "Content-Type: application/json" --request POST --data '{"jsonrpc":"2.0","method":"aboutModulesList","params":{"query":{}},"id":1}' http://<LOCATOR_IP>:8080

Start Bridge Node

Start the bridge node with

ros2 launch bosch_locator_bridge bridge.launch.xml bridge_ip:=<HOST_IP> locator_ip:=<LOCATOR_IP> locator_user:=<USER> locator_password:=<PASSWORD> scan_topic:=<SCAN_TOPIC> enable_odometry:=<ENABLE_ODOM> odom_topic:=<ODOM_TOPIC>

where

  • <HOST_IP> is the IP address of the computer the bridge is to be started

  • <LOCATOR_IP> is the IP address of the computer where the ROKIT Locator is running

  • <USER> and <PASSWORD> are the credentials to log into the ROKIT Locator

  • <SCAN_TOPIC> is the topic name of the laser scans

  • <ENABLE_ODOM> is a boolean that describes whether you want to forward odometry ROS messages to the ROKIT Locator

  • <ODOM_TOPIC> is the topic name of the odometry

Since the Laser Localization Software is running in docker, the <HOST_IP> has to be set to docker0 ip address (172.17.0.1) instead of localhost ip address (127.0.0.1) when the user program providing the laser data runs on the same machine.

For additional parameters please refer to the launch file bridge.launch.xml.

Start Visual Recording

Then, make sure there are laser scans published on <SCAN_TOPIC>, and start the visual recording with e.g.

ros2 run rviz2 rviz2 -d $(ros2 pkg prefix bosch_locator_bridge)/share/bosch_locator_bridge/config/locator_bridge_visual_recording.rviz
ros2 service call /bridge_node/start_visual_recording bosch_locator_bridge/srv/StartRecording "name: 'ROS-Quickstart-$(date -Isecond)'"

You should see the laser scans, the robot position and its previous path, and the recording built up over time.

Stop Visual Recording

When you are done, you can stop recording with

ros2 service call /bridge_node/stop_visual_recording std_srvs/srv/Empty

Create Map From Recording

Now, create a map from your recording with

ros2 run rviz2 rviz2 -d $(ros2 pkg prefix bosch_locator_bridge)/share/bosch_locator_bridge/config/locator_bridge_map_creation.rviz
ros2 service call /bridge_node/start_map bosch_locator_bridge/srv/ClientMapStart

When the map has been created, it must be sent to the map server and set as the active map.

ros2 service call /bridge_node/send_map bosch_locator_bridge/srv/ClientMapSend
ros2 service call /bridge_node/set_map bosch_locator_bridge/srv/ClientMapSet

Start Localization

Finally, you can start the localization with

ros2 run rviz2 rviz2 -d $(ros2 pkg prefix bosch_locator_bridge)/share/bosch_locator_bridge/config/locator_bridge_localization.rviz
ros2 service call /bridge_node/start_localization std_srvs/srv/Empty

You can set the initial pose of the robot by clicking the “2D Pose Estimate” button in RViz, and then set the pose in the map.

Stop Localization

When you are done, you can stop the localization with

ros2 service call /bridge_node/stop_localization std_srvs/srv/Empty

Map Expansion

  1. Record and build the prior map (map name: priormap) as usual.

  2. Start localization on this prior map and move until the system is localized.

  3. Make a note of the pose and do not move

  4. Enable map expansion

    rosservice  call /bridge_node/enable_map_expansion "prior_map_name: priormap"

  5. Start visual recording and use the following to visualize the prior map

    rosrun rviz rviz -d `rospack find bosch_locator_bridge`/config/locator_bridge_visual_recording_with_prior_map.rviz

  6. Use the pose in step 3 to set the current pose in the recording

    rosservice call /bridge_node/recording_set_current_pose "pose:
    x: -0.357
    y: 32.3
    theta: -0.23"

  7. Drive around to record the new area as an extension

  8. Stop visual recording

  9. Start mapping with the recording including the initial pose (map expansion is still enabled)

    rosrun rviz rviz -d `rospack find bosch_locator_bridge`/config/locator_bridge_map_creation_with_prior_map.rviz

  10. Disable the map expansion

    rosservice  call /bridge_node/disable_map_expansion

Nodes

bridge_node

This node provides an interface to the localization client.

ROKIT Locator Configuration

To correctly forward the laser scan data, it is important that ClientSensor.laser.type is set to simple, and that ClientSensor.laser.address is set to the IP address (with port) of the computer the bridge is running.

Subscribed Topics

  • /scan (sensor_msgs/msg/LaserScan)

    The laserscan topic of the first laser to translate and forward to the ROKIT Locator.

  • /scan2 (sensor_msgs/msg/LaserScan)

    The laserscan topic of the second laser to translate and forward to the ROKIT Locator.

  • /odom (nav_msgs/msg/Odometry)

    The odometry topic to translate and forward to the ROKIT Locator. Only used when enable_odometry is set to true.

  • /initialpose (geometry_msgs/msg/PoseWithCovarianceStamped)

    Set a seed pose to help localization. RViz by default sends a message of this type and topic when the user clicks on the “2D Pose Estimate” button in the toolbar.

Published Topics
Map Creation
Map Recording
Localization
Map Expansion
Services

server_bridge_node

This node provides an interface to the map server.

Start Server Bridge Node

Start the server bridge node with

ros2 launch bosch_locator_bridge server_bridge.launch.xml bridge_ip:=<HOST_IP> locator_ip:=<LOCATOR_IP> locator_user:=<USER> locator_password:=<PASSWORD>

where

  • <HOST_IP> is the IP address of the computer the bridge is to be started

  • <LOCATOR_IP> is the IP address of the computer where the ROKIT Locator is running

  • <USER> and <PASSWORD> are the credentials to log into the ROKIT Locator

Services

Caveats

ROKIT Locator closes connection

The ROKIT Locator performs a strict input validation checks and closes the connection, if it receives data that is outside of its specified range. If you see error messages of this kind in the output of the ROS bridge:

Connection reset by peer

Double check the data sent and compare it with the acceptable values in the ROKIT Locator API documentation.

Also peek in the LocalizationClient’s syslog file (see the ROKIT Locator documentation) for hints (usually validation of ... failed).

Error message: SENSOR_NOT_AVAILABLE

This can happen if you switch the ROKIT Locator into a mode where it requires e.g. laser data, but none is available (e.g. no laser data is sent with a few hundred miliseconds after the mode switch).

To avoid this, make sure LaserScan messages are sent to the bridge before switching the ROKIT Locator mode.

Support of earlier versions of ROKIT Locator

Note that version 1.6 and earlier of ROKIT Locator were developed for ROS Galactic, and bosch_locator_bridge_utils does not built with ROS Humble. But if you want to build bosch_locator_bridge only, you can ignore bosch_locator_bridge_utils by putting a file named COLCON_IGNORE in the package folder:

touch locator_ros_bridge/bosch_locator_bridge_utils/COLCON_IGNORE

But if you need the bosch_locator_bridge_utils package, see issue #50.

If you have version 1.9, checkout the corresponding tag:

git checkout 2.1.12 -b humble-v1.9

If you have version 1.8, checkout the corresponding tag:

git checkout 2.1.10 -b humble-v1.8

If you have version 1.6, checkout the corresponding tag:

git checkout 2.1.9 -b galactic-v1.6

And if you have version 1.5:

git checkout 2.1.8 -b galactic-v1.5

And if you have version 1.4:

git checkout 2.1.6 -b galactic-v1.4

And if you have version 1.3:

git checkout 2.1.4 -b galactic-v1.3

And if you have version 1.2:

git checkout 2.1.2 -b galactic-v1.2