Marking and Vision System Tracks NASCAR Spec Engine Components
The North American Stock Car Racing (NASCAR) has adopted a new spec engine for its Camping World East and West series that uses many off-the-shelf parts to provide performance and durability at only about one-half the cost of custom-built engines. Each of the major parts in the new motor has a 2D barcode that can be read in seconds by a handheld scanner, greatly reducing the inspection time at the track. The marks need to be positioned in very specific, often difficult-to-mark locations on the parts so they can be inspected easily before and after the race (to prevent the use of illegal parts that would increase the power of the engine).
Wegner Motorsports, which provides spec kits and assembled engines, overcame this application challenge with the Columbia Marking Tools 3 in 1 Marking System, which produces two-dimensional (2D) barcodes using dot peen, scribe and laser marking methods so it can mark virtually any surface. A key to the success of the marking system is its integration of a Cognex In-Sight 5100 vision camera. The camera instantly grades the mark to verify that it can be read during the track-side inspection process—which happens to use Cognex DataMan ID readers.
Spec engine development
NASCAR’s new engine is based on General Motor’s Gen-three small-block V-8, commonly referred to as the LS2. The engine costs only a fraction of a custom-built motor because it uses stock components, including block and cylinder heads with the original bore and stroke dimensions. Race-specific components include JE-forged aluminum pistons, a Comp Cams cam and pushrods, a Holley 830-cfm four-barrel carburetor, Lunati crankshaft and rods, Edelbrock intake, a custom Stewart Components water pump, and Del West titanium valves.
The engine produces 520 ft-lbs of torque and 625 hp at a maximum of 8,000 rpm. Wegner adopted a unique tagging system that provides positive identification for each component on the engine to prevent cheating. The 2D barcode has a series of dots arranged in a square that is very difficult to reproduce or counterfeit. Its information includes the type of component, manufacturer, date of sale, and serial number.
Wegner faced a difficult challenge in producing the 2D barcodes on certain engine components. Parts such as the crankshafts, connecting rods, pistons, blocks, cylinder heads, intake and exhaust manifolds and fuel pumps are made from a range of different materials, including cast iron and hardened 4140 steel, with a wide range of surface treatments such as nitriding and anodizing. What makes these parts particularly difficult to mark is that the location of the mark is often determined by the need to make it accessible for these inspections. NASCAR inspectors use a Cognex wireless handheld DataMan 7000 series scanner to inspect the engines both before and after the race to ensure that only legal parts are used.
While at a racing show, Wegner managers saw Columbia’s Marking Tools 3 in 1 Marking System, which can perform all three of the major marking methods: dot peen, scribe, and laser marking. The peen/scribe marking unit uses an impact stylus for peen marking or a diamond tip for the quiet scribe marking of text or graphics into hard or soft surfaces. The marking force can be actuated either electrically or by air. Switching from dot peen to scribe marking is performed by flipping a switch and changing the stylus. The system also has available a multi-faceted diamond tool for extended tool life.
The laser-marking unit of the system uses a compact, low-cost adjustable diode laser with variable power, from 0 to 50 watts. The laser module takes less than five minutes to retrofit to the main unit. The various marking units are mounted to an x-y slide that is driven by precision linear ballscrews.
When scribing or laser marking the parts, Columbia’s machine displaces material in a way that leaves specifically recessed areas formed of grooves and surrounded by ridges of displaced material that look like round indentations. These grooves and ridges form a very reflective multifaceted data cell, with very high contrast between the grooves and the unscribed or laser marked surface. A vision system can easily distinguish the grooves, evening the presence of extraneous marks or deposits.
Columbia calls the marks produced by this method Square Dots. They can be produced at very high speeds with grade A readability, which is equivalent to 1,200 reads per second with no variations. The Columbia model DPS-LR-150 machine used by Wegner has a 4-in. x 6-in. marking window. A rotator attachment provides the ability to mark the periphery of round parts.
A readable 2D barcode is critical to the integrity of these engines. If the barcode cannot be read during the pre-race inspection, there is a chance that the car will not be allowed to race. If it cannot be read in the post-race inspection, the results of the race will be in doubt.
To verify the readability of each part, every 2D barcode is scanned while being generated. To meet this requirement Columbia integrated a Cognex In-Sight 5100 vision sensor into its marking machine. Andy Ruzzin, vice president of sales for Columbia Marking Tools, said, “There are a number of vision companies, but we recommend Cognex vision sensors because of their 2D barcode reading technology. NASCAR made the same decision by selecting Cognex handheld scanners for reading spec engine barcodes. Cognex’s In-Sight Explorer software also provides more options for reading a 2D barcode, and makes it easier to develop a vision application.”
The In-Sight 5100 vision sensor acquires up to 60 full frames per second with 8 bit images. Its die-cast aluminum housing and sealed industrial M12 connectors eliminate the need for additional enclosure hardware, and it is rated for shock and vibration to IEC specifications. When used with the included lens cover, the sensor achieves an IP67 (NEMA 6) rating for dust and washdown protection on the factory floor.
Columbia Marking Tools used the In-Sight Software Development Kit to develop a user interface with a point-and-click setup. The kit let developers integrate In-Sight images, graphics, and data into custom programs, exposing only the functionality required for end users to configure In-Sight and monitor its operation, while preserving Columbia’s custom interface.
Ease of configuration helped Wegner Motorsports get the new marking system up quickly. Wegner general manager Dan Timm said, “We got the marking machine up and running within four hours of unloading it off the truck.”
Having three marking options makes it possible to produce a readable mark on the most difficult applications, said Timm. “We find that we use the scribe method on the majority of our parts, the dot peen method on very hard parts, and laser marking on a few specialized applications such as marking valves.”
The integrated Cognex In-Sight vision sensors reliably grade the 2D barcode mark, added Timm.
“I was amazed that the vision system could read the mark with only simple LED lighting and without special shrouding,” said Timm. “Later, when we are putting the parts together into kits, we scan the parts again using the Cognex DataMan wireless handheld scanner, which is the same model used by the NASCAR inspectors. This tells us exactly which part has gone into which kit, making it possible later to trace its history, if necessary.”