Each implant is placed in the cell of a blister pack and each batch of parts identified by a code. Packaged implants are inspected in their individual cells as they pass under a desktop machine-vision system.

Low-volume production often goes hand-in-hand with high costs, particularly when it involves small devices. Take Swiss-based DePuy Spine, for instance. It makes small implants such as screws for spinal surgery that call for 100% inspection and identification.

Quality control was previously a manual operation, but with regulations becoming stricter, some level of automation was needed. So engineers at Swiss-based Compar, combined a two-axis desktop robot with Cognex vision and developed a system more suitable and less expensive than a fully automated one.

The Cognex camera mounts on the desktop robot's Y-axis, while blister packs being inspected move under the camera in the X-direction. Several inspections can be done on each cell or pocket in the pack while a barcode scanner simplifies data recording. Inspected data are compared against set values and permissible tolerances, and an alarm sounds when the system detects a faulty part. Quality assurance personnel then remove the part for manual inspection. The inspection machine ensures compliance to 21 CFR Part 11 by tracking and documenting results for each batch.

Compar engineers add that the proposed equipment should easily adapt to other inspection and identification tasks, such as inspecting surfaces, part layouts, and solder points.