Shenzhen Beilai Technology Co.,Ltd

OpenPLC Application Case | ARMxy Empowering Automotive Welding Line Automation

2025 07/31

In the era of smart manufacturing, automotive production lines are embracing more intelligent, flexible, and efficient control systems. This case study showcases how the ARMxy embedded controller combined with modular I/O boards and OpenPLC is used to coordinate robot welding stations in a car body assembly line.

? Application Scenario

In a car manufacturing plant’s body-in-white (BIW) workshop, six welding robots must operate in tight synchronization. The system needs to coordinate signals from fixtures, adjust welding current dynamically, and manage post-weld cooling — all with high flexibility and easy configuration for different car models.

The client required:

Precise welding sequence control

Remote debugging and PLC program updates

Flexible parameter adjustment for new vehicle models

Modular expansion to adapt to equipment changes

? System Configuration

✅ Main Controller: ARMxy Embedded Edge Gateway

Runs OpenPLC, Node-RED, Docker, with remote management capability

✅ X-DI Digital Input Module

Detects fixture clamping and safety signals

✅ X-DO Digital Output Module

Controls welding gun on/off and cooling water valves

✅ Y-AO Analog Output Module

Outputs 4–20mA signal to regulate welding current (0–500A)

? How It Works

Using OpenPLC logic:

Fixture Detection (DI):

Once all clamps are in position, the welding sequence is triggered.

Dynamic Current Control (AO):

The AO module outputs a 4–20mA signal to adjust the welding power source based on plate thickness.