How to Use the VDA-5050-Connector

Aim of the Repository

The idea of the repository is to ensure an easy connection of the VDA 5050 with ROS. It is intended to ensure an immediate integration into ROS. For ease of use, you can customize all interfaces by adapting the configuration files in the /config folder to match your requirements.

The VDA5050 connector only covers ROS communication, which means that all messages coming from the main control must be published to ROS topics. Since MQTT is widely used to communicate from the main control to AGVs, an example implementation to achieve compatibility between ROS and MQTT is shown below.

Prerequisites

• This project was tested under Ubuntu 18.04 LTS + ROS Melodic (Python 2.7) and Ubuntu 20.04 LTS + ROS Noetic (Python 3.7).
• ROS must be installed and a workspace (e.g., catkin_ws) must be initialized.

Since the VDA5050 connector solely relies on ROS communication, any other communication protocol must be translated accordingly. VDA5050 specifies the use of MQTT as it is widely used for communication between the main control and AGVs. In the following we will describe a method for translating MQTT messages to ROS messages. For this, we use the ROS MQTT bridge to connect to a server via TLS. Of course, any other solution can be used as well. Names of outgoing and incoming topics can be adapted accordingly.

Installation of the ROS MQTT bridge

Clone the mqtt_bridge repository and install the additional requirements to run the bridge (see https://github.com/groove-x/mqtt_bridge#prerequisites).

git clone https://github.com/groove-x/mqtt_bridge.git

NOTE
Be careful to choose the correct branch. If you plan to use ROS melodic, checkout the branch called “python2.7”.
The master branch will only work with ROS noetic.

Installation of the VDA5050 connector

Go to your catkin workspace and cd into the src folder:

cd ./src

Clone the VDA-5050-Connector repository:

git clone https://github.com/idealworks/VDA-5050-Connector.git

Clone the vda5050_msgs repository:

git clone https://github.com/ipa320/vda5050_msgs.git

NOTE
Although the vda5050_msgs repository provides most of the required message types, some additional message types must be defined in order to provide the full functionality of VDA5050.
Since we have not send a merge request to the vda5050_msgs repository yet, do the following after cloning the vda5050_msgs repository:

• copy all .msg files in /msg of the VDA-5050-Connector repository into the /msg folder of the vda5050_msgs repository

• replace the CmakeLists.txt in the vda5050_msgs repository with the one within the /msg/CmakeLists of the VDA-5050-Connector repository

After cloning all required repositories, build your catkin workspace.

Customization of the configuration

There are three distinct parts of the configuration that must be customized to fulfill your connection requirements.

1. ROS MQTT bridge server connection (“mqtt_bridge_tls.yaml”)
2. ROS MQTT bridge topic configuration (“mqtt_bridge_topics.yaml”)
3. VDA5050 connector topic configuration (“vda5050_connector_topics.yaml”)

Each of them is represented by a single configuration file in the /config folder. In the following sections we will go through them step by step.

NOTE
Since we wanted to use the ROS MQTT bridge out of the box with no further customization,
all required parameters configuration files can be found in the /config folder in the VDA-5050-Connector repository (and not in the mqtt_bridge repository).

ROS MQTT bridge server connection

To make the ROS MQTT bridge work with TLS, complete the “mqtt_bridge_tls.yaml” configuration file in the /config folder.