Challenge
The chip layout differs by product, so fixed coordinates cannot locate the inspection point
Destructive inspection has to be carried out at precisely located points on the product. But this line receives products whose chip layouts differ from one another. With coordinates taught once into the robot, the inspection point drifts every time the product changes, and the same problem appears whenever the product is placed even slightly off.
Solution
Two cameras narrow down step by step, from rough coordinates to precise corner coordinates
AIM Vision recognizes the chip layout with 2D vision, corrects the position from the product corners, and then the inspection is performed. Coordinate acquisition was split into two stages.
- The first camera images the whole product to obtain rough position coordinates.
- The second camera acquires precise coordinates at four corners for each of those positions.
- The IAI Cartesian robot moves to the inspection point using those precise coordinates. The robot is controlled over TCP communication through its XSEL controller.
- A robot program editing screen and an inspection corner editing screen were developed in-house and included.
Robot, 2D vision and the inspection process are controlled together on a single platform.
Results
Nobody re-teaches coordinates — the inspection point follows the product even as it changes
- When a product with a different chip layout comes in, the layout is recognized and the inspection points are recalculated — no fixed coordinates per product.
- Position is corrected from the product corners, so the inspection point follows even when the product is placed off-center.
- Precise coordinates at four corners are acquired step by step with two cameras, so a wide field of view and high precision are not demanded of a single camera.
- A robot program editing screen and an inspection corner editing screen were developed in-house and included — inspection points are edited on this screen.
