3D Inspection of Radially Symmetrical Parts:

Accurate Inspection on Randomly Oriented Cylindrical Surfaces

Cylindrical surfaces of three-dimensional products such as bottles, vials and cosmetic containers are difficult to inspect. Cameras often cannot be placed in the ideal locations, the part may have unknown orientation, or the surface to inspect may span multiple camera views. Virtual Imaging Inspection solves these problems.

Virtual Imaging Inspection uses images acquired from one or more cameras to generate a seamless and undistorted image of an object surface. As long as an interesting feature appears in one or more of the physical camera images, it can be inspected.

Advantages

Handles random part rotation, tilt and position

Camera placement is flexible

Entire curved surface can be inspected at once

Simple part handling (gapping)

Non-contact 100% inspection upto 1200 PPM at standard resolution

More robust than traditional multiple cameras approach

Faster and less expensive than line scan camera solution

Simplified inspection setup

Example Applications

Bottle label inspection

The label on a bottle often wraps entirely around a bottle. Inspection using one camera is not possible without expensive and slow part handling. With Virtual Image Inspection, multiple cameras are used to simultaneously image the entire circumference, and the images are combined.

Compensation is made for

Bottle label inspection. Top images) Four images of the exterior of the bottle. Middle image) The rendered virtual image. Bottom image) Sample inspections.

Part handling is simplified

Vial inspection

Multiple images are combined to render a virtual image of the circumference of a vial. Compensation is also made for the transparent nature of the vial.

 

Vial label inspection. Left images) Two images of a transparent vial. Middle image) The rendered virtual image. Right image) Sample inspections.

Cosmetics inspection

Multiple images are combined to render a virtual image of the circumference of a cosmetic container. Compensation is made for mirroring.

Cosmetics inspection. Left image) Direct frontal view and back reflections from two mirrors. Right image) The rendered virtual image.

Example Inspections

Label placement & verification

Day-lot code (OCV & OCR)

1D & 2D ID reading

Print quality inspection

Out-of-roundness

Gauging (without a telecentric lens)

 

Three virtual images of a golf ball. Part of the ball is omitted for illustrative purposes