Today’s new 3D metrology technology is making an impact on the design of championship Indy racecars. In this webcast, engineer Brent Knutson of Andretti Autosport® discusses the state of 3D metrology and laser scanning technology and its applications in design, reverse engineering and quality assurance practices. Advancement in, and simplification of, technologies such as articulating arms are gradually pushing these functions out of the metrology lab and onto shop floors. At Andretti, this movement has led to better and faster measurements that reduce work time and costs. Best practices in tactile and non-contact measurement are highlighted, in addition to 3D laser scanning to reverse engineer body molding, and ensuring the concentricity of wheels and flatness of surfaces.
Andretti Autosport and the IZOD IndyCar Series
Headquartered in Indianapolis, Indiana, Andretti Autosport is the only INDYCAR team competing in all four steps of the Mazda Road to Indy driver development system, fielding multiple entries in the IZOD IndyCar Series, Firestone Indy Lights, Pro Mazda Championship and USF2000 National Championship. Andretti has achieved a 27 percent win rate in 10 seasons of operation, with 45 IndyCar victories in 162 races and a historic 1, 2, 3, 4 finish at the 2005 Grand Prix of St. Petersburg.
Key achievements include:
• Four IZOD IndyCar Series championships (2004, 2005, 2007, 2012)
• Two Firestone Indy Lights titles (2008, 2009)
• One USF2000 championship (2010)
• Two Indianapolis 500 wins (2005, 2007)
The IndyCar Series, the nation's premier openwheel racing series, offers one of the most diverse and challenging schedules in motorsports, with the renowned Indianapolis 500 as its flagship annual event. Races are held across the United States and other locations worldwide on ovals, permanent road courses and temporary street courses.
IndyCar and 3D Metrology Equipment and Processes
The IndyCar Series features aerodynamically configured open-wheel, single-seat, open-cockpit cars with front and rear wings. The 1,580 pound Twin Turbo V6 2.2L Chevy engines run on 100 percent fuel-grade ethanol and achieve 3.5 mpg. IndyCar Series cars produce approximately 650 horsepower and reach top speeds of about 230 mph. A modern day Indy car accelerates from 0 to 100 mph in less than three seconds and generates 5,000 pounds of downforce at 220 mph.
The IndyCar series is unique in that course types vary from race to race; requiring significant adjustments to the cars on a weekly basis to best accommodate oval, street or road courses. The same chassis is used between tracks, but the configurations and builds of the cars must continually change. With extremely short turn-around times (about one day) to tear down, rebuild and then break down cars to pack and ship them, Andretti Autosport relies on 3D metrology technology to identify reliable, consistent methods of achieving and maintaining performance advantages throughout the racing season within a continually shifting system.
Andretti daily utilizes three types of 3D metrology equipment, manufactured by FARO, for a variety of applications:
• Vantage Laser Tracker - a highly accurate, portable coordinate measuring machine
• 12’ Edge ScanArm - a contact/non-contact measurement system featuring a hand-held laser scanner
• Gage Measuring Arm - a 3D gauge for smaller parts, made specifically for shop floor personnel
These tools provide improved measurement consistency, reduced inspection time, rapid protopyping, an enhanced ability to reverse engineer complex parts and surfaces, and detailed 3D modeling, critical to Andretti for meeting stringent league-mandated technical specifications.
A flat plate in the Andretti shop holds an entire car. A one-foot grid is drilled across the plate, with holes in it, each stamped with an alphanumeric code. The Vantage Laser Tracker scanned each of the holes to record a computerized grid of the plate. With a car on the plate, the ScanArm touches the plate to record those points, recognizing where the arm is in relation to the plate. Each chassis has also been recorded with dimensions and key points that allow easy reference to datum features, so once the chassis points and the plate points are loaded, and the plate and the car have been touched by the ScanArm, the arm can be moved anywhere around the plate. By navigating easily throughout the plate grid, rather than investing extra time in accomplishing best fit moves through the car, improvements have been made in both efficiency and reliability.
Two different software programs are employed to post-process the data: Siemens NX for Design, an integrated product design solution that streamlines and accelerates the product development process by importing ScanArm point measurements; and Geomagic scanning and 3D image software to process 3D scans into polygon and surface models. FARO software is used for simple measurements and point gathering.
Design, Reverse Engineering and Quality Assurance Applications
Parts are broken down and re-set often, even for the same race, because some parts have different specifications for qualifying than for racing. Using the ScanArm and Gage ensures that the parts being used are within specifications for both safety and performance, and will pass both qualification and racing tests. The ScanArm is also used to check wheels for trueness, face angles, wobbling and balance issues, among other specifications, as wheels are changed out often.
Andretti engineers scanned, for recordkeeping, a front wing assembly that demonstrated a consistent performance advantage. The front wing assembly incorporates many adjustable aspects and is a temporary item often damaged during races. With data from this scan, the benchmark front wing assembly can be rebuilt to exact specifications. In addition, a rear crash box was scanned to a 50 percent scale model piece. Rather than completely re-designing the crash box to a smaller scale by hand drawing, the same goal was accomplished in considerably less time with this digital scan.
Seats are custom designed for every driver, typically requiring a significant investment of the driver’s time. With 3D metrology, individual seat molds are scanned and then machined from a light foam material, saving three pounds compared to the original process while providing the opportunity to re-create the identical seat whenever it needs to be replaced. Different brands and models of helmets are also scanned to analyze their unique characteristics and to determine varying levels of efficiency and aerodynamics that may impact performance.
Laser scanning is also being used by Andretti Autosport to address aerodynamic inconsistencies among its 10 cars, which have been built identically, in theory, by using the same base mold. In scanning the undertrays of each car and comparing them through computer-aided design to the perceived best car, many variables can be detected and adjusted.
Future 3D processing goals for Andretti include rapid full car inspection and easier movement of the ScanArm. To shorten the time cars spend on the flat plate to just 5-10 minutes, the company is designing a system using four ScanArms and one Vantage Laser Tracker to allow four people to simultaneously measure key points on the car. Combining these two tools will allow the arm to move freely around the car, affording unique measurements at a faster pace by eliminating the need to determine common points between locations and any stacking errors from multiple fit moves. These new processes will better utilize the available workforce and save valuable time while compiling a more comprehensive record of the car’s performance.
Positioning for the Next Win
Since Andretti Autosport began utilizing 3D metrology in 2007, these processes have advanced to improve reverse engineering, and the design and construction of small parts, in addition to speeding up normal processes. More common usage by a variety of shop floor personnel has helped to improve reliability and reduce the man hours required, with better results. The tools are highly accurate, further reducing the margin of error, with the precision of the scanner edge at plus or minus .0014.
The 2012 Indianapolis 500 Pole came down to 9.168 inches over 10 miles.(Unfortunately, the Andretti car was just inches from the prize.) In such a highly competitive series, Andretti Autosport is looking to most effectively utilize 3D metrology in the shop, and plans to soon bring some of this cutting-edge, portable technology on location. Exploiting the smallest details can optimize the performance of every car, with the end goal of gaining those valuable inches on the track.
Data Acquisition Engineer Andretti Autosport
Brent Knutson, a Data Acquisition Engineer for the Andretti Autosport team, is responsible for radio communications, electronics and wiring harnesses for the cars and at the track. He travels with the team to all races and currently spends most of his time working on James Hinchcliffe’s #27 GoDaddy Chevrolet. Knutson is a graduate of Purdue University in West Lafayette, Indiana.