The overall aim of the Radicle projects is to develop a laser welding adaptive control system which can integrate sensor data from 3 loops in real time by adjusting laser parameters to deliver welded joints with zero defects. The control system will include in process monitoring control, fault prevention / fixing pre and post welding measurement.
Radicle project partners include four large, end user partners which includes Roll Royce, GE, GKN and CRF (Fiat). The successful implementation of Radicle technology through Project Partners and the wider industry, will enable the project to have the following impacts:-
• An increase in Health & Safety benefits
• An increased productivity of up to 30% resulting in reduced emissions, reduced energy usage, reduced rework and a reduction in the need for final NDE testing
• Reduce floor space requirements by removing the need for large welding room enclosures
The Radicle project contributes to the wider European 2020 targets by:-
• Reducing energy usage and greenhouse gas emissions
• Increasing employment for 20-64 year olds
• Increasing R&D spend
• Increasing education, particularly third level education
Laser welding is a high performance joining process which provides significant benefits over more conventional methods, such as arc based welding. The global market for using laser equipment for material processes has grown 50% since 2004 and is valued in excess of €10 billion per annum. The automotive industry has led in the implementation of laser welding for structures such as BIW (Body in White). The aerospace industry are now also using this process for various applications in joining reactive metals such as titanium alloys. Welds in the aerospace undergo 100% post weld inspections using X-ray technologies and welds with greater levels of porosity than relevant standards specify, have to undergo rework which can severely impact the economic benefits of laser welding processes.
Figure 1: Overview of the Radicle Concept
Radicle is a 45 month project and is delivered in three distinct phases. Phase 1 was about the specification and preparation of samples and components for initial characterisation and subsequent testing. Phase 2 , development of sensors and the algorithm whilst phase 3 is the integration, demonstration and validation of the RADICLE system, firstly in the lab and subsequently on MTC’s laser welding cell.
The final RADICLE system developed in the project delivers a new laser welding monitoring and adaptive control architecture integrating multi-sensor data to deliver high–quality weld joints. This will help companies across different industry sectors produce laser welded components – Smarter, Faster and to Higher Quality, Reducing Post Manufacturing Inspections Costs.
The RADICLE project has created:
- A modular system allowing users to configure the system to their specific applications. The system includes:
o Photodiodes (off-axis and co-axial)
o Seam tracking camera
o Permatrack software that provides live weld quality feedback to the operator on welding stability.
o Co-axial process zone imaging camera
o Keyhole depth monitoring sensor
o Microphone for acoustic emission analysis
- Welding process widows for a number of ferrous and non-ferrous materials and joint configurations, supported by welding data from industrial case studies;
- Weld data handling and analysis routines to extract valuable information from the welding process monitoring sensors;
- The development of the architecture for a multi sensor adaptive control system for laser welding including a machine learning algorithm able to:
o Interpret raw sensor data and associated welding quality parameters.
o Generate the process window heatmap from the sensor data.
o Allow in line weld quality limits to be set and monitored live and provide an alarm when weld quality has deviated from the acceptable limits.
Figure 2: Final project leaflet