Measurement and Inspection of Skull Pins

The LVR Inspection System has been used to measure and inspect skull pins. They are “pointed”, like bone screws, but not threaded. Click images for larger views.

As with bone screws, the robot puts the pin between the camera and a light source and rotates it for multiple views.

Calculate Holding Power During Inspection

The integrated measurement capabilities of the LVR Automated Inspection System, with its ability to store a measurement process and export the results to Excel, make it possible to calculate holding power for each bone screw in an inspection run.  A trend analysis can be performed over one or more runs to monitor the ongoing accuracy of manufacturing process.

Click to download a copy of the LVR-Trend-Analysis spreadsheet.  It uses some randomness functions to simulate variability during the manufacturing process.

analysis-screen-shot

Integrated Measurement

The LVR Inspection System is becoming an easy to use micrometer.  We’ve recently added software functions that allow the operator to accurately dimension an entire part or any part of that part.  In addition the manual measurement process, shown in the video below, can be saved as  “macro” and repeated during the automated inspection process.  Adding measurement to inspection scenario does not significantly increase inspection time.  Finally, the measurement results can be saved to Excel spreadsheets for subsequent review and analysis.

Inspection, Sorting, and Packaging

When parts from mixed runs are to be inspected and sorted or the quality control process calls for verifying and sorting parts, the LVR inspection system will fit the need.  The video below shows the system picking up screws, determining their length, performing a full inspection against the first article of inspection, then putting the screws that pass inspection into the appropriate packaging.

Annotated Image of LVR Inspection System

In an recent post on this website, we released a video showing the LVR system’s ability to adapt to new part configurations. Here, we’ve annotated an image to show all the parts of the inspection system.

annotated

Legend

1. Computer
2. Robot control software
3. Image of plastic part
4. Teach pendant
5. Bone screw
6. Pneumatic gripper
7. R12 robot
8. Rack of screws
9. Plastic part in rack
10. Nexus Android teach console
11. Small pneumatic gripper on interchangeable tool adaptor
12. Electric gripper on interchangeable tool adaptor
13. Rack for unused grippers

 

 

Automating Inspection in Multi-Part Environments

One of the things we’ve learned about orthopaedic implant manufacturing is that parts are produced in runs, so an inspection system needs to be nimble enough to inspect more than one part type or size.

The LVR Inspection System’s robot is capable of changing its own grippers, so changing the type of part under inspection is as simple as a selection on the computer controlling the system. The robot will attach the gripper designed for that part, adjust its inspection parameters, and continue with its inspection.

Reducing the cost of warranties for implants

Comparison of knee against CAD in false color

Comparison of knee against CAD in false color

A recent article in Consumer Reports advocates warranties for hip and knee implants. If device manufactures were to offer such warranties, they could reduce their exposure by inspecting each and every implant part during the manufacturing process.

“While patients may be told by their surgeon how long a device can be expected to last, they rarely get a guarantee in writing since most hip and knee implants do not come with a warranty,” said Lisa McGiffert, director of Consumers Union’s Safe Patient Project.

The LVR inspection system provides this functionality, inspecting parts like bone screws or other small implants. It’s robot arm can segregate defective parts, with no human intervention. In addition, the LVR system inspects each part through an entire rotation on one axis, providing a three dimensional analysis.

The LVR system’s robot can change its own grippers; the system is not limited to a single part or profile. Once programmed, it can switch from one product inspection to another in a matter of moments.

The cost of the LVR system and its automated, reliable, and repeatable procedures provide manufacturers with the confidence to develop warranties like those suggested by Consumer Reports at a reasonable cost.