Overview
Industrial Raspberry Pi RevolutionPi is a small industrial control mounted on a DIN rail. RevolutionPi (RevPi for short) has a complete set of IO and bus modules, which can communicate with all common analog and digital sensors, actuators and bus systems as well as TCP-IP-based networks.
In addition, RevPi runs the Linux operating system, which makes it a versatile and versatile solution. 
In this case, RevPi connects the Kawasaki FS03N robot and the PLH3D-6W-XF laser engraving head through the DIO expansion module. Through the pre-installed open source Node-RED software, logical control, communication channels and powerful dashboards are established, and the robot running status can be remotely accessed and controlled through the web interface.
Hardware connection
The picture below is the physical picture of the hardware connection in this case. On the far left is the 24V power supply, which is used to power the device. Next to the power supply is the RevPi Core module and connected to the DIO expansion module.
The Core module is connected to the network through a network cable and can be accessed and communicated remotely. The DIO module connects the robot and the laser engraving head for logic control. To the right are two AllDAQ adapters, which are used to connect the 14 digital inputs and 14 digital outputs of the RevPi DIO expansion module to the I/O board of the robot.
The small blue device next to it is a coupling relay, which is used to turn on or turn off the power of the laser engraving head. On the far right is the digital-to-analog converter, which can convert the digital signal from the robot to the 0-10V analog signal of the laser engraving head.
Node-RED dashboard
In this case, the Dashboard component of Node-RED is used to establish an operation dashboard to monitor the working status of the robot and perform switch control. Because the Core module has been connected to the Ethernet, in addition to the IO interface, it can also be controlled by TCP or UDP communication.
In this example, by switching the switch on the robot controller, the state of the robot can be changed from TEACH mode to REPEAT mode and displayed on the dashboard.
Click the Motor Power button on the dashboard to turn on the motor power and switch to the ON state.
You can also control the robot to move in a certain direction through the dashboard (in millimeters). 
Click the Homing symbol in the middle to return the robot to its original position. If the robot is in the home position, the "house" symbol will light up.
Node-RED program flow
The logic control and communication of RevPi to the robot are realized by establishing Node-RED flow.
The UI interface introduced above is also established through this process. In the Node-RED flow, the string exists in the form of msg, and the effective information is in the payload, and can be sent to the robot via TCP or UDP.
Remote monitoring
Node-RED supports access to the dashboard through a web-based browser in the local area network. Therefore, you can use a tablet or smart phone to monitor the robot status and control it.
In this case, you can send the start "Laser-Auftrag gestartet" (Laser-Auftrag gestartet) message via the mobile phone to make the robot start working. And after the job is over, you can receive the prompt message "Laser-Auftrag beendet" (laser job has been completed) on the mobile phone.
appendix
About RevPi
Revolution Pi (RevPi for short) is an industrial PC based on the expansion of Raspberry Pi. The three basic modules of this series are all installed in a slender DIN rail housing, which can be seamlessly expanded through various suitable I/O modules and fieldbus gateways, and can be easily configured through a preset graphical configuration tool.
In order to achieve industrial applicability in compliance with EN 61131-2 or IEC 61131-2 standards, we use Raspberry Pi computing modules as the basis. The module looks like a memory stick, but it does not have any external interface.
We equip the Raspberry Pi computing module with external interfaces that comply with all important industry standards. In terms of software, Revolution Pi has a specially modified Raspbian operating system that is equipped with real-time patches and is compatible with most applications developed for Raspberry Pi.
About
Node-RED Node-RED is a powerful tool for building IoT applications. It uses a visual programming method that allows developers to connect predefined code blocks (called "nodes", Node) to perform tasks. The connected nodes are usually a combination of input nodes, processing nodes and output nodes. When they are connected together, they form a "flow" (Flows).
Node-RED was originally an open source project developed by IBM at the end of 2013 to meet their needs for quickly connecting hardware and devices to Web services and other software. As a glue for the Internet of Things, it quickly developed into a universal programming tool for the Internet of Things.
Importantly, Node-RED has accumulated a large number of users and quickly formed an active developer community, who can develop new nodes, while allowing programmers to reuse Node-RED code to complete various tasks.
RevPi and the Node-RED programming environment are pre-installed, and users can use it directly. And we provide nodes specially designed for RevPi. Node-RED will become a powerful tool for you to quickly develop IoT applications!