Laser scanning services at GKS Inspection Services Inc. recently saved a major producer of trucking accessories a minimum of $8,000 in the design of light-emitting diode (LED) marker lights for over-the-road trucks by quickly identifying a problem that would have taken more than a week to solve using conventional engineering methods. A research group in Tucson, Arizona was given the challenge of developing the complicated optics needed to meet regulatory requirements for a marker light with a single LED. The initial prototype did not meet the requirements even though optical simulation showed the design should work. Also, touching the delicate plastic part with the probe of a coordinate measuring machine would have damaged it, so the part was sent to GKS Inspection Services’ laser scanning service bureau in Minneapolis where any physical object within a wide-size range can be converted into a 3D model in a day or two.

One research group representative explained.  “The Federal Motor Vehicle Safety Standards specify very strict regulations for marker lights to ensure that the trailer is visible from any angle, and even though design analysis had predicted that the component would work, test results showed that it was not putting out light in all the right places,” he said.  As soon as they saw an as-built model of the prototype, he said the problem was obvious.  “There were tiny ripples on one of the optical surfaces that, even though they were within specs, produced a 7-degree slope error.”  The problem was solved by using a newly modeled, rippled surface and altering other locations of the optical part.  In addition, the specifications of the plastic part were changed to include a tolerance for the angle of the critical surface.

 “The laser scanning service saved us a large amount of time that we would have otherwise had to spend on laborious troubleshooting, which ended up saving money for our client,” he said.  He estimated that it would have taken at least a week with conventional methods to find the problem. At a typical engineering hourly rate of $200 per hour, costs would have mounted very rapidly.

 “To the best of my knowledge, there is no technology outside of laser scanning that could have solved this problem so quickly,” he concluded. “Contact measurement methods have a tendency to damage sensitive components and they often can’t collect enough points to positively determine what is causing the problem. On the other hand, laser scanning provides the complete geometry of the part, in a fraction of the time, without the need for touching it.

“GKS Inspection Services’ service bureau approach fits our needs perfectly. Whenever we need it, we can have our parts scanned by some of the top people in the business. Yet, we don’t have to buy and maintain equipment and train our staff to use it.  We plan on using it in the future whenever we need to troubleshoot a project, or just to learn more about the fabrication process.”