Automotive Testing Technology International 1998 – 2008

Cover 1-04 2/24/04 3:49 PM Page 1 Cover 2-04 5/10/04 8:19 AM Page 1 Cover 2-04 9/15/04 4:32 PM Page 1 Cover 2-04 5/10/04 8:19 AM Page 1 Cover 2-04 9/15/04 4:32 PM Page 1 Cover 3-04 js 11/15/04 4:16 PM Page 1 AUTOMOTIVE TESTING TECHNOLOGY INTERNATIONAL INTERNATIONAL TECHNOLOGY TESTING AUTOMOTIVE THE MAGAZINE DEDICATED TO AUTOMOTIVE TESTING AND DEVELOPMENT THE MAGAZINE DEDICATED TO AUTOMOTIVE TESTING AND DEVELOPMENT THE MAGAZINE DEDICATED TO AUTOMOTIVE TESTING AND DEVELOPMENT NEW LOOK! GREAT FEATURES, FRESH STYLE, MORE TECHNOLOGY NEW LOOK! GREAT FEATURES, FRESH STYLE, MORE TECHNOLOGY “THE AMBITION IS TO TAKE SOMEWHERE IN THE REGION OF SIX MONTHS OUT OF THE DEVELOPMENT TIME” P.86 testing technology international testing technology international testing technology international testing technology international February 2004 testing technology international May 2004 September 2004 May 2004 September 2004 November 2004 MAY 2008 MAY September 2004 May 2004 September 2004 November 2004 May 2004

Four years of track- inspired development C6 Tata

“We weren’t overrun with Americans, but “We weren’t overrun with Americans, but those that have come in brought a great those that have come in brought a great Nano EXCLUSIVE: Developing the world’s deal of experience. They know how to make deal of experience. They know how to make volume cars at a profit and they have very volume cars at a profit and they have very cheapest car SLK“CAE in SLK’s development cut the number SLK“CAE in SLK’s development cut the number good processes so that when you sign a car good processes so that when you sign a car of mules and prototypes by nearly a third; off, it will actually work as it is supposed to” of mules and prototypes by nearly a third; off, it will actually work as it is supposed to” Ford Focus just 60 test vehicles were used during the Land Rover’3 just 60 test vehicles were used during the Land Rover’3 “The Philippines created some problems for us. four-year program” four-year program” The team struggled to make the allotted mileage in time due to the high traffic density there” IN THIS ISSUE… Rob Oldaker ALSO IN THIS ISSUE ALSO IN THIS ISSUE Ferrari development

MG Rover’s director, product development SPECIAL FOCUSES INTERVIEWS NORTH AMERICA 2004 SHOW ISSUE Don Goodwin We talk Detroit development Engine test 2010 How to... Assess SPECIAL FOCUSES INTERVIEWS NORTH AMERICA 2004 SHOW ISSUE Don Goodwin We talk Detroit development Engine test 2010 How to... Assess THE LAB ISSUE A rare insight into the race-proven SHOW ISSUE SHOW ISSUE Durability NVH Crash Ride & handling to the VP of Chrysler’s The future of vehicle The experts specify vehicle dynamics to the VP of Chrysler’s The future of vehicle The experts specify vehicle dynamics technologies ready for the road and engineering, on developing to survive Environmental assessment Dave Pickett, director, test operations, Ricardo AUTOMOTIVE Environmental assessment Dave Pickett, director, test operations, Ricardo AUTOMOTIVE SHOW REVIEW The latest viable We look at how to Numerous new crash Get it sideways scientific labs and testing in the world’s a test chamber for Our look at best scientific labs and testing in the world’s a test chamber for Our look at best LTD EVENTS & MEDIA UKIP BY PUBLISHED NVH testing Jost Capito, director, Team RS, Ford Motor Co NVH testing Jost Capito, director, Team RS, Ford Motor Co AUTOMOTIVE TESTING alternatives to specify your new test rigs are coming and ride potholes AUTOMOTIVE proving grounds original Motor City the next decade test practices AUTOMOTIVE proving grounds original Motor City the next decade test practices Ultimate force Data acquisition technologies Hans Folkesson, senior VP, R&D, Volvo Car Corp TESTING EXPO Data acquisition technologies Hans Folkesson, senior VP, R&D, Volvo Car Corp TESTING EXPO EXPO NORTH AMERICA proving grounds sound suite onto the market in the laboratory Expo preview Tomorrow’s world TESTING EXPO TESTING EXPO 2004 PAGES 76 TO 82 From road to the lab – the changing NORTH AMERICA NORTH AMERICA face of automotive durability work PAGE 64 Automotive Testing Expo Europe 2004 We asked Byron McCormick, executive director EUROPE 2004 October 27, 28, 29 2004 EUROPE 2004 October 27, 28, 29 2004 Over 300 exhibitors of fuel cell commercialization activities, GM, SHOW ISSUE: PREVIEW SHOW ISSUE: PREVIEW SHOW ISSUE: PREVIEW SHOW ISSUE: PREVIEW Industrial revolution? 25, 26, 27 May 2004, Messe Stuttgart, Germany AND PROGRAM INSIDE AND PROGRAM INSIDE AND PROGRAM INSIDE AND PROGRAM INSIDE Catering to the evaluation needs of www.testing-expo.com to predict the future of vehicle testing PAGES 70-82 PAGES 62 TO 69 PAGES 70-82 PAGES 62 TO 69 Cover 1-04 2/24/04 3:49 PM Page 1 off-highway vehicle manufacturers Cover 2-05 js 4/29/05 9:54 AM Page 1 SHOW PREVIEW AUTOMOTIVE TESTING TECHNOLOGY INTERNATIONAL INTERNATIONAL TECHNOLOGY TESTING AUTOMOTIVE THE OFFICIAL MAGAZINE OF AUTOMOTIVE TESTING EXPO NORTH AMERICA – NOVI, MI. 26, 27, 28 OCTOBER 2005 The official magazine of auTomoTive TesTing expo euRope – sTuTTgaRT, geRmanY, 9, 10, 11 maY 2006 The official magazine of auTomoTive TesTing expo euRope – sTuTTgaRT, geRmanY, 9, 10, 11 maY 2006 THE OFFICIAL MAGAZINE OF AUTOMOTIVE TESTING EXPO EUROPE – STUTTGART, GERMANY, 9, 10, 11 MAY 2006 THE OFFICIAL MAGAZINE OF AUTOMOTIVE TESTING EXPO EUROPE 2005 – STUTTGART, GERMANY, 31 MAY, 1 & 2 JUNE THE OFFICIAL MAGAZINE OF AUTOMOTIVE TESTING EXPO EUROPE – STUTTGART, GERMANY, 8, 9, 10 MAY 2007 automotive testing technology international automotive testing technology international automotive testing technology international automotive testing technology international February 2004 automotive testing technology international May 2005 September 2005 November 2005 November 2005 May 2006 March 2007 MARCH 2007 MARCH

Four years of track- September 2005 November 2005 November 2005 May 2006 May 2005 inspired development Let’s get physical Advances in proving grounds to meet increasing demands of C6 vehicle manufacturers

599“You could work with 1,000GTB prototypes and the car may still not work properly. For this Flying Spur Jaguar XK car, we had over 30 development vehicles” “The body-in-white was the biggest design “We got our first evaluation car off the production line in and engineering challenge for us, because it September last year. But getting that car was a traumatic Bugatti Veyron Bugatti Veyron is aluminum. Although we have the experience experience for a production line that was already producing from the XJ, and some of the specifi cations “I drove one of the cars and I was shocked a little because “I drove one of the cars and I was shocked a little because the GT. Even though the two cars share 60 per cent are the same, we have evolved the build of the quality and the performance. It was a really bad day” of the quality and the performance. It was a really bad day” common parts, it was still disruptive and a challenge” process, and the design is unique to this car” Wolfgang Schreiber, head of development, Bugatti Rob Oldaker Wolfgang Schreiber, head of development, Bugatti

MG Rover’s director, product development AUTOMOTIVE TESTING EXPO EUROPE 2006 PREVIEW SHOW PREVIEW Wind talkers Come fly with us Ground breaking? New columnist SHOW PREVIEW Ulrich Eichhorn Working in the air Videophone home Two tribes ShOw reVIew Mike Donoughe On track Quiet streets Inside line ShOw reVIew Mike Donoughe On track Quiet streets Inside line SHOW PREVIEW Bob Lutz Make a gain Water fable Toyota tour

NORTH AMERICA 2005 SHOW ISSUE and engineering, on developing to survive All the news from We take a look at Imagining the many Take a tour around Automotive Testing Are aero-acoustic How to create cars Special focus on test Alex Geisler, auto Automotive Testing Bentley’s director Development of the The communication We explore how Ford All the news from Chrysler’s body-on- We take a look at Imagining the many Take a tour around Chrysler’s body-on- LTD EVENTS & MEDIA UKIP BY PUBLISHED Ford Getting ready for “We have enormous News of the latest Why developing a car An exclusive look T

THE REAL-WORLD ISSUE Expo Europe 2005, wind tunnels an that can fly – and the tracks: what’s new lawyer for Duane Automotive Testing frame technology VP testing technologies consequences of a the Pratt & Miller site, Expo North America of engineering talks world’s largest plane technologies that will has enabled design T Automotive Testing testing technologies consequences of a the Pratt & Miller site, frame technology VP he Automotive Testing human capital at GM, technologies in the that ‘drives’ on water around the Japanese he MOTO 31 May to 2 June, indulgence or good implications on the and how to create Morris, explains October 26, 27, 28 2005 about the creation – and you thought help change the lives and engineering teams MOTO Expo North America on the rise and rise designed for the world without the home to Corvette Expo North America on the rise and rise designed for the world without the home to Corvette Interviews Expo Europe: 9, 10, enough to do whatever auto industry to help is not dissimilar to the company’s expanded Stuttgart. See p.92 development sense? auto test industry the ultimate facility the law is an elk Novi, Michigan of luxury vehicles you had it tough! of auto engineers to work together 2005, held in Novi, MI of the Dodge brand motorsports market humble automobile Racing and the C6.R Expo preview 2005, held in Novi, MI of the Dodge brand motorsports market humble automobile Racing and the C6.R 11 May 2006 we want to do” data acquisition work road-based version European R&D center r

r Tomorrow’s world SPO SPO Automotive Testing Expo Europe 2004 Maurizio Reggiani r r

We asked Byron McCormick, executive director T ISSU T ISSU Over 300 exhibitors Head of R&D, Lamborghini

of fuel cell commercialization activities, GM, e e 25, 26, 27 May 2004, Messe Stuttgart, Germany Ralf Effenberger www.testing-expo.com to predict the future of vehicle testing MD, European Test Services Mondeo Blue Oval cuts one-third cut from its development costs

Cover 2-05 js 4/29/05 9:54 AM Page 1 AUTOMOTIVE TESTING TECHNOLOGY INTERNATIONAL INTERNATIONAL TECHNOLOGY TESTING AUTOMOTIVE

Cover.indd 1 9/9/05 11:35:27 INTERNATIONAL TECHNOLOGY TESTING AUTOMOTIVE Cover107.indd 1 26/2/07 11:29:14Cover206.indd 1 4/10/06 10:20:07 AM THE OFFICIAL MAGAZINE OF AUTOMOTIVE TESTING EXPO EUROPE – STUTTGART, GERMANY, 8, 9, 10 MAY 2007 THE OFFICIAL MAGAZINE OF AUTOMOTIVE TESTING EXPO EUROPE – STUTTGART, GERMANY, 8, 9, 10 MAY 2007 THE OFFICIAL MAGAZINE OF AUTOMOTIVE TESTING EXPO EUROPE 2005 – STUTTGART, GERMANY, 31 MAY, 1 & 2 JUNE The official magazine of auTomoTive TesTing expo euRope – sTuTTgaRT, geRmanY, 9, 10, 11 maY 2006 THE OFFICIAL MAGAZINE OF AUTOMOTIVE TESTING EXPO NORTH AMERICA – NOVI, MICHIGAN OCTOBER 24, 25, 26 2007 automotive testing technology international automotive testing technology international automotive testing technology international March 2007 November 2006 May 2005 March 2006 September 2007 MARCH 2007 MARCH SEPTEMBER 2007 SEPTEMBER November 2006 March 2006 May 2005 Let’s get physical Advances in proving grounds to Commodore meet increasing demands of GM’s new global RWD architecture VE developed by the Australians vehicle manufacturers

Flying Spur “We got our first evaluation car off the production line in Dodge Caliber September last year. But getting that car was a traumatic experience for a production line that was already producing “We developed a new durability cycle because of the type the GT. Even though the two cars share 60 per cent of car Caliber is, compared to Neon. It meets the demand of Caparo T1 DETROIT FOCUS what both compact cars and crossover vehicles need to be” common parts, it was still disruptive and a challenge” “It has been a peculiar concept. It Ford Taurus was a lot more than just developing Blue Oval re-christens PLUS SHOW PREVIEW Wind talkers Come fly with us Ground breaking? New columnist AUTOMOTI ShOw PrevIew Josef haberl On your bike Law and order Into the wind the car; we had no experience of the Five Hundred sedan PUBLISHED BY UKIP MEDIA & EVENTS LTD EVENTS & MEDIA UKIP BY PUBLISHED PUBLISHED BY UKIP MEDIA & EVENTS LTD EVENTS & MEDIA UKIP BY PUBLISHED Ford Automotive Testing Are aero-acoustic How to create cars Special focus on test Alex Geisler, auto Getting ready for The director of safety Why two fewer wheels How to help prevent We provide a tour

ve Automotive Testing at BMW reveals his doesn’t mean half recalls and warranty around Visteon’s running a business” Cerberus THE REAL-WORLD ISSUE Expo Europe 2005, wind tunnels an that can fly – and the tracks: what’s new lawyer for Duane THE AWARDS ISSUE Jeff Zyburt T

Interviews 31 May to 2 June, indulgence or good implications on the and how to create Morris, explains e Expo Europe: 9, 10, company’s future the headaches for issues thanks to new climatic tunnel The future for Chrysler is on both STING Life for Chrysler after sides of the Atlantic, according Stuttgart. See p.92 development sense? auto test industry the ultimate facility the law is an elk 11 May 2006 plans for crash testing motorbike engineers more durability work in Kerpen, Germany separation from Daimler e

to the vehicle development boss Maurizio Reggiani XPO e

Head of R&D, Lamborghini U Motor city Track changes AWARDS SPECIAL r OP

REVEALED: The winners of the inaugural Automotive e Auto test community remains Come trackside as we look at vehicle Ralf Effenberger P development in the motorsports world Testing Technology International Awards 2006 MD, European Test Services Mondeo rev strong despite OEM troubles Blue Oval cuts one-third cut from its development costs I ew Cover 3-04 js 2/28/05 5:48 PM Page 1 AUTOMOTIVE TESTING TECHNOLOGY INTERNATIONAL INTERNATIONAL TECHNOLOGY TESTING AUTOMOTIVE AUTOMOTIVE TESTING TECHNOLOGY INTERNATIONAL INTERNATIONAL TECHNOLOGY TESTING AUTOMOTIVE Cover406.indd 1 22/11/06 17:04:00 INTERNATIONAL TECHNOLOGY TESTING AUTOMOTIVE Cover107.indd 1 26/2/07 11:29:14 Cover307.indd 1 20/9/07 16:07:00 AUTOMOTIVE TESTING TECHNOLOGY INTERNATIONAL INTERNATIONAL TECHNOLOGY TESTING AUTOMOTIVE THE OFFICIAL MAGAZINE OF AUTOMOTIVE TESTING EXPO EUROPE – STUTTGART, GERMANY 6, 7, 8 MAY 2008 THE OFFICIAL MAGAZINE OF AUTOMOTIVE TESTING EXPO EUROPE – STUTTGART, GERMANY 6, 7, 8 MAY 2008 “THE AMBITION IS TO TAKE SOMEWHERE IN THE REGION OF SIX MONTHS OUT OF THE DEVELOPMENT TIME” P.86 BIGGEST EVER ISSUE • AUTOMOTIVE TESTING EXPO NORTH AMERICA 2006 PRE VIEW THE OFFICIAL MAGAZINE OF AUTOMOTIVE TESTING EXPO EUROPE 2005 – STUTTGART, GERMANY, 31 MAY, 1 & 2 JUNE AUTOMOTIVE TESTING TECHNOLOGY INTERNATIONAL AWARDS 2007 SPECIAL ISSUE – TURN TO PAGE 60 FOR WINNERS automotive testing technology international PREVIEW automotive testing technology international March 2008 March 2008 September 2006 March 2005 Nov/Dec 2007 MARCH 2008 MARCH MAY 2008 MAY MARCH 2008 MARCH NOVEMBER/DECEMBER 2007 NOVEMBER/DECEMBER March 2005 September 2006

“By using parts that perform as well as they do on XK, such as the suspension, we had a great platform to build on. This gave us reliability and confi dence in Tata XF the prototype phases” Nano EXCLUSIVE: Developing the world’s cheapest car Freelander “Putting this car through a typical Land Rover test program was a level of commitment to the product Hummer H3 and a measure of how tough the “To save time, we took data from the off-road test targets were. It will do things that trips to the Rubicon and put it into a multi-axis IN THIS ISSUE… simulator. A complete durability life cycle normally IN THIS ISSUE... we don’t specify it of being capable IN THIS ISSUE... IN THIS ISSUE... Ferrari development of doing, such as boulder crawl” takes six months, but it took us four weeks in the lab” Green future A rare insight into the race-proven Crash 2028 Green future Discover what safety labs What are manufacturers doing technologies ready for the road AUTOMOTIVE TESTING EXPO NORTH AMERICA 2006 What are manufacturers doing SHOW PREVIEW Derrick Kuzak Long arm of the law EMC prepared Bench stressed Raymond Freymann Breaking the law Ring master Data managed Chamber made will look like in 20 years to clean up auto development? LTD EVENTS & MEDIA UKIP BY PUBLISHED to clean up auto development?

Automotive Testing Ford’s VP, product We follow the folk Renault opens the Is simulation and We spoke to BMW’s Legal experts on how A guide to the ultimate How to make the Anechoic test LTD EVENTS & MEDIA UKIP BY PUBLISHED PUBLISHED BY UKIP MEDIA & EVENTS LTD EVENTS & MEDIA UKIP BY PUBLISHED

PUBLISHED BY UKIP MEDIA & EVENTS LTD EVENTS & MEDIA UKIP BY PUBLISHED Ultimate force Expo North America, development, The given the task of doors to its new virtual prototyping set THE DATA ISSUE head of research to cope with lawsuits lap of the Nürburgring, numbers count, chamber know- Motorsports Simulation update From road to the lab – the changing Novi, MI: October 25, Americas, talks getting police cars state-of-the-art EMC to take over the world and innovation about or better still, avoid and why you must test plus new acquisition how is improving Simulation update GT- GT- Porsche Motorsport and Andretti “We did not have benchmark “We did not have benchmark Full details on the multi-million face of automotive durability work PAGE 64 26 and 27 2006 platform sharing ready for duty facility in Paris, France of engine evaluation hydrogen possibilities them in the first place at the legendary track technology profiled at a rapid rate Full details on the multi-million vehicles because we have aimed Green Racing teams talk testing vehicles because we have aimed hi-tech investment by Toyota Industrial revolution? hi-tech investment by Toyota at the top level for every aspect” Catering to the evaluation needs of Expo review at the top level for every aspect” SRT interview Automotive Testing Expo SRT interview off-highway vehicle manufacturers Kipp Owen, director of Chrysler’s Kipp Owen, director of Chrysler’s SHOW PREVIEW North America 2007 in Novi performance brand speaks out R performance brand speaks out R

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UKIP Media & Events Ltd. 1998 - 2008 10 years of Automotive Testing Technology International and looking towards 2018... Simulation Chassis control simulation processes CarSim from Mechanical Simulation enables GM engineers to simulate vehicle maneuvers in a lab long before a vehicle is available for testing Ric mousseau, general motors proving grounds

A screenshot of a CarSim GUI and simulation animation

n To ensure that every vehicle’s chassis maneuver to measure ESC performance, and world, GM engineers use a product from control system performs in a safe, reliable, the NHTSA fishhook test to quantify tire lift- Mechanical Simulation called CarSim in and unobtrusive manner, extensive vehicle off during extreme emergency lane change a wide range of vehicle design and testing testing is performed at General Motors’ maneuvers. GM has made a tremendous tasks. Simulation presents an opportunity to Milford Proving Ground (MPG), and various investment in facilities, equipment, reduce costs, improve quality, and shorten remote winter test sites. This includes manpower, and training to support this high time to market. Vehicle maneuvers can be vehicle testing to measure the performance level of vehicle performance testing. executed by the computer in a controlled of ABS, traction control, and electronic At GM, every opportunity needs to be laboratory environment which lets engineers stability control (ESC) systems during explored to maximize vehicle safety and evaluate system performance months before various braking, acceleration and turning performance while simultaneously reducing a physical vehicle is available for testing. maneuvers, and combinations thereof. the cost of testing vehicles. The capability Simulation is less costly than physical These vehicle tests are performed on dry of vehicle dynamics simulation has reached testing since vehicles do not need to be pavements, wet pavements, snow surfaces, a level of sophistication where it can be equipped with expensive data acquisition and ice surfaces. Other tests include relied upon to replace some physical vehicle hardware every time a test needs to be the FMVSS-126 sine with dwell (SWD) testing. In several regions throughout the run. Finally, the test reports generated by

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dynamic simulation can be made to a combination of performance constants This common database also lets any GM appear the same as the physical vehicle and multidimensional lookup tables. engineer in other global regions import test reports that are generated at the proving Typically, the data is obtained from the data into CarSim and start running ground. This test report format, familiar vehicle design data and from physically simulations. After the vehicle dynamics to GM vehicle development engineers, measuring complete vehicles and/or their model is verified with standard handling helps facilitate the validation of the subcomponents. Vehicle data includes, for tests, it is ready to be integrated into simulation models. example, sprung mass, CG position, roll, a HIL simulator. Hardware-in-the-loop (HIL) simulation pitch, and yaw inertia, shock absorber force- The brake buck contains all the brake is extensively used by GM MPG engineers components, including vacuum assist, to support the integration of chassis control master cylinder, rotors, calipers, and the systems. The fundamental idea behind “CarSim is ideally suited proper line lengths. A hydraulic actuator HIL is to use simulation for the vehicle for simulating vehicle applies a force to the master cylinder input systems that can be modeled with high rod to simulate application of pedal force. confidence and actual vehicle hardware performance, because The rotors, of course, do not spin, but are for the systems that are difficult to model an important source of brake compliance. in real-time software. For example, the its data requirements Pressure transducers measure the brake hardware part of an ABS HIL simulation are compatible with GM’s caliper pressure at each corner. The signals may include the brake controller/modulator are fed back to the brake model in the from an actual base brake system with the development process” CarSim simulation and are scaled by tables vacuum assist and a master cylinder. This to estimate applied braking torques. The system is difficult to model in software due velocity data, and suspension kinematic buck also includes the brake ECU, which to the complex non-linear temperature- and compliance data. Another important controls the brake pressure modulator. dependent performance of the hydraulic set of parameters includes the tire force and The brake fluid system is bled, as in an system. However, the rest of the vehicle can moment data, which is typically measured actual car, to remove air bubbles that can be modeled with higher confidence and is over the expected load, slip, and camber potentially degrade system performance. well suited for simulation. This example is operating range. All of this data is available The real-time simulator computer often referred to as a wet bench, because from GM internal databases, which, coupled executes the CarSim model in real time and it includes the hydraulic system. Another with the CarSim data structure, makes provides the interface to the brake buck. approach is to model only the base brake the vehicle modeling process very efficient. It digitizes the analog brake line pressure system and brake modulator in software – so the only hardware is the ABS brake Hardware In The Loop Brake Buck controller. This is often referred to as Host Computer (Running CarSim Real Time Simulator a dry bench. and Matlab/Simulink) At the GM MPG, the wet bench approach Electrical is most commonly used because it has Signals proved to yield results close to real-world testing. The HIL system consists of the CarSim-RT vehicle dynamics simulation program, brake buck, and real-time simulation computer. The CarSim GUI, CAN Bus Controller Signals Line Pressures Pedal which controls data input and program Force Pedal Travel execution, resides on the host computer. The CarSim solver, which performs the vehicle dynamics simulation, resides on the real-time simulator. The figure shows Above: HIL simulation and signal flow how line pressure measurements, CANbus messages, and other signals pass to and from the brake buck to the simulator. CarSim is ideally suited for simulating vehicle performance, because its data requirements are compatible with the GM vehicle development process. The vehicle dynamics model has 10 degrees of freedom (DOF): six define position and attitude of the vehicle sprung body, and the other four define the jounce positions for the unsprung bodies. Additional DOF model tire spin, steering system rotation, and brake system dynamics. Other unsprung body motions, such as suspension toe and camber, are defined through constraint equations. The CarSim models are defined with Histogram of 1.0 second yaw rate ratio

Automotive Testing Technology International Report 2008 173 Simulation

signals, which are used to estimate brake The SWD steering profile required by torques in the vehicle dynamics model. the FMVSS 126 regulation consists of three The real-time simulator also provides the quarters of a 0.7Hz sine wave, followed by CANbus signal interface for the brake 0.5 second dwell at 1.07 second as shown ECU and digital IO for the relevant in the figure. The last quarter of the sine vehicle sensors. It also provides diagnostic wave completes the profile. The asymmetry messages to allow the ESC to function. in the steering profile promotes vehicle Most of the simulated vehicle maneuvers spin at large steer angles. Steering wheel angle primarily involve braking, with little or no The SWD test procedure involves throttle application. For these maneuvers, steering the vehicle with this profile the CarSim powertrain model works well. scaled by multiples of a reference steer However, the maneuvers that activate the angle measured on the vehicle at 0.3g lateral traction control system require an internally acceleration in a ramp steer test. The test developed, more detailed powertrain model starts with a steering multiplication factor developed in Simulink, which executes of 1.5 and ends when the steer amplitude Yaw rate Yaw in parallel with the CarSim simulation is larger than either a multiple of 6.5 on a separate processor. times the reference steer angle or 270 A common application of HIL vehicle degrees of steer. Metrics calculated from dynamics simulation at GM MPG is the the test data include the 1.0 second and FMVSS-126 Sine with Dwell (SWD) test 1.75 second yaw rate ratios (measures of maneuver. This maneuver is severe enough vehicle spin), and the lateral displacement to induce oversteer intervention for all at three-quarter steer cycle (measure of

vehicles equipped with ESC systems. When vehicle maneuverability). The FMVSS-126 Lateral disp the regulation comes in full effect in 2011, regulation requires the vehicle to achieve all vehicles less than 4,545kg (10,000 lb) a lateral displacement of at least 1.83m SWD steering profile and test evaluation metrics GVWR sold within the USA must pass this during the maneuver, while the 1.0 second test. With a few exceptions, this test will yaw rate must to be less than 35% of the which can be completed in 24 hours. cause vehicles without the benefit of ESC peak value during the maneuver, and The histogram plots illustrate how the to spin out of control. the 1.75 second yaw rate less than 20% variables can affect the test metrics of the of the peak. 1.0 second yaw rate ratio and the lateral Understanding how the test metrics displacement requirement. Despite the can be influenced by vehicle build and variability, the yaw rate ratio is always test-surface variability is an important part much lower than the 35% limit and the of the certification process. Model lateral displacement is always well in excess parameters that influence the vehicle of the 1.83m requirement. Tests such as handling test metric include tire cornering these help show that the control system force properties, weight distribution, is sufficiently robust to ensure compliance suspension stiffness and damping, and with the regulations. test entry speed. Studies using Monte Being able to perform these tests Carlo analysis to randomly vary the within the simulation environment vehicle parameters within the CarSim illustrates the value of vehicle dynamic HIL simulation have proved useful for software like CarSim as the foundation for A screenshot of Simulink understanding vehicle control system the vehicle development process. CarSim robustness. Typically these studies may fits well into the vehicle development involve over 1,000 HIL simulation runs, process and complements test resources. HIL simulation has proved to be a very effective tool for extensive robustness studies that require a very large number of vehicle tests. CarSim is also used to isolate problems that are difficult to reproduce in actual vehicle testing environments, and to identify problematic vehicle configurations for testing. In summary, HIL simulation is a powerful tool for optimizing vehicle performance testing, which has been shown to reduce cost and improve quality. n

lll Contact Ric Mousseau or Tom Klingler, GM Proving Ground Email: [email protected] Email: [email protected] Histogram of lateral displacement metrics Web: www.carsim.com

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