Phast results

A combination of digital photography and measurement technologies could help form complex car panels more efficiently, according to steel manufacturer

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Working with metrology specialist Geodelta, the company has developed a system known as PHAST (PHotogrammetric Automated STrain measurement system) which uses photogrammetry to measure accurately the strain within a pressed body panel.

Strain is produced when an object is deformed, and being able to measure it accurately is important for processes involving the forming of metals. For car makers, it's an important parameter, as the percentage strain in a panel — how much it has been deformed from its original shape — can determine how it flows when it is pressed.

Traditional strain analysis methods allow only small areas of a pressed component to be measured, usually by examining how far pre-placed markers have moved apart. This makes the process for a large panel extremely time-consuming.

The Corus system, developed at the company's R&D centre in IJmuiden, in the Netherlands, uses digital photography to take images of a pressed panel from up to 20 different positions. 'The number depends on the part geometry,' explained Hans Brouwer, Corus RD&T customer support engineer. 'Each new image enhances the reliability of the determined results, and improves the accuracy of the co-ordinates of the surface points.'