... methodology is a benchmark for new standardsIRVINE, Calif., Feb. 27 /PRNewswire/ -- Volvo vehicles are known for their ruggedness, durability and, of course, legendary safety. What may not be known is the Swedish marques' use of electronic robotic vehicle testing versus good ole carbon-based life forms (humans). Towing tests are an important part of Volvo's rigorous durability testing, and probably the only manufacturer to have its own range of trailers plus robotic control driving management system.Favorable characteristics for any tow vehicle are: good engine performance with high torque at low rpm, coupled with smooth shifting transmissions, positive steering control, suspension attributes, and, of course, braking systems are all key elements to towing performance and safety. Vehicle attributes The vehicle's suspension must not be too soft, preferably level, when towing as the angle of the car's wheels and therefore its grip on the road can change under heavy rear-end focused loads. "We need to look at many different vehicle attributes while towing different kinds of loads, and the best towing test driver runs on 12 volts," according to Stefan Svensson who is responsible for vehicle dynamics at Volvo Car Corporation, Sweden. "When test towing, you should always try to maintain a steady course and avoid unnecessary movements of the steering wheel. Our robotic control system is accurate 100% of the time." Robotic system Volvo uses robotic controls to avoid inconsistent or subjective behavior when test towing. From human to human test driver, there are so many variations. And when coupled with different towing loads, road conditions, weather conditions, time of day, and differences in vehicle dynamics (i.e. throttle position, steering wheel movement, and braking), accurate measurements are nearly impossible. "What we needed to achieve was consistency in as much of the testing program as possible. By removing our human test drivers, we're much closer to gathering true empirical data than ever before," according to Stefan. "Our robotic control system can run the course the same exact way ... every time. We can even program the system by adding in over-control to create an unstable trailer, which is something we want our test engineers to experience." New ISO standard Volvo helped create a new ISO standard for towing tests which involves measuring the lateral acceleration of the trailer, the angle between the car and the trailer, the angle of the steering wheel, the yaw angle and actual vehicle speed. All measured values must be within certain criteria for the car to be approved by Volvo. "The new ISO test standard is an off-shoot of our own internal testing criteria," according to Stefan. "Seems we're on the right track, considering ISO is using our methodology as a benchmark for new standards." Extreme durability tests Volvo has two extreme testing facilities. From bitter winter cold in Sweden to blistering summer hot in Death Valley, California, they use an armada of about 35 trailers ranging in size from 1,500 pounds to nearly 4,400 pound Volvo is prepared to run the tow testing gauntlet. If that's not extreme enough, Volvo uses the 'hill from hell' in Death Valley which is a 14 mile, 7% grade usually where July temperatures run 115 degrees. "That's 115 degrees air temperature; black pavement is much hotter," comments Stefan. "This is a great test for our engine cooling system." Towing capacities Volvo tow hitches are tested to the same extremes as its vehicles. All Volvos are factory pre-adapted for tow hitches with anchorages engineered into the vehicle platform. For each model there is a match tow hitch with the following capacity(1): S40 2,000 pounds and 165 tongue weight V50 2,000 pounds and 165 tongue weight S60 3,300 pounds and 165 tongue weight V70 3,300 pounds and 165 tongue weight XC70 3,300 pounds and 165 tongue weight S8 3,300 pounds and 165 tongue weight XC90 5,000 pounds and 500 tongue weight (1) Check Volvo Owner's Manual for towing details. Volvo has been building cars with Safety in mind for over 75 years. The current 2006 model line-up of Volvo Cars includes: the award-winning new S40 and its wagon counterpart the all-new V50; the award-winning XC90; the sporty S60 sedan -- including the award-winning performance sedan -- S60 R and the performance wagon version -- V70 R; the S80 luxury sedan; the versatile V70 wagon and rugged XC70 (Cross Country); and the soon-to-be released new Volvo C70, the convertible with the innovative retractable hardtop. Source: Volvo Cars of North America |