Weld seam tracking system is easy to install

Citation

(2001), "Weld seam tracking system is easy to install", Industrial Robot, Vol. 28 No. 6. https://doi.org/10.1108/ir.2001.04928fad.008

Weld seam tracking system is easy to install

Weld seam tracking system is easy to install

Keywords: Lasers, Welding, Machine vision

Low cost and simplicity of set-up are features of Laser Probe 2000, the latest automatic weld seam tracking product from Meta Vision Systems. Suitable for all welding processes and seam types, the vision-based system is capable of sensing and compensating for any deviation from the programmed weld path (see Plate 6).

Laser Probe 2000 uses technology that is already proven in Meta's previous systems, of which over 200 have been installed. It is suitable for new or retrofit installation on TIG, MIG/MAG, submerged arc, plasma and laser welding applications, and can support welding process speeds up to 8m/min. Typical payback time for such systems is under one year.

Plate 6 Laser Probe 2000, the latest automatic weld seam tracking system from Meta Vision Systems, features low cost and simple set-up

Ease of operation via an operator pendant and simple interfacing with welding machine controllers are complemented by a high degree of versatility. A pre-teach facility is available for multiple seam types and adaptive control of welding parameters allows in-cycle adjustments to be made automatically. This gives Laser Probe 2000 an advantage in minimally manned situations.

The system comprises a sensor head mounted a known distance ahead of the welding torch, a camera cable, a control box, an operator pendant and, if required, a set of motorised slides. The sensor head incorporates one or two laser diodes which project a laser stripe onto the seam surface at an angle. It also incorporates a CCD camera equipped with filters that block out extraneous light including the welding arc so that the system concentrates on the laser stripe.

The stand-off distance (height) from the surface can be set by the angle at which the laser stripe is projected; at the correct distance the stripe will be centred in the camera shot. In addition, the seam is detected by a fall-off or variation in the reflection of the laser stripe. As the sensor is mounted forward of the welding torch it provides a look-ahead facility. Combined with use of image processing software, it allows any off-sets to be accurately calculated and fed into the control system. Adjustments can then be made to the torch path fully automatically, ensuing that it remains positioned over the seam.

A variety of standard seam types are pre-programmed into the system for easy selection via the operator's pendant. However, non-standard seams can be accommodated using Meta's Laser Probe Tools software, which runs under Windows 98. In addition to configuring the system for customised seam tracking, Laser Probe Tools supports a variety of useful functions including system performance evaluation as well as general system configuration and automatic process adjustments including head angle adjustment for different seams.

For further information contact Andrew Pryce, Sales and Marketing Director, Meta Vision Systems Ltd, Oakfield House, Oakfield Industrial Estate, Eynsham, Oxfordshire OX8 1TH, UK. Tel: +44 (0)1865 887900; Fax: +44 (0)1865 887901; E-mail: sales@meta-mvs.com