Mobile Data Acquisition and Field Testing

Vehicles and their components undergo numerous test runs – from the concept, from prototype towards production; from simulation conducted on a computer to tests in test stands, and mobile tests in the field. Measurement equipment and DAQ systems are needed for:

• Road Load Data Acquisition (RLDA) mainly on test tracks in proving grounds but also in the field, measuring vehicle response to typical load cases
• Vehicle Dynamics, Brakes (ABS, ESP), Tyres, Advanced Driver Assistance (ADAS)
• Powertrain and overall drivetrain performance testing
• Endurance testing and winter and summer (cold and hot) country testing with extreme ambient and temperature conditions and grounds

Under test, vehicles and components are subjected to real conditions of use. They are sometimes exposed to extreme conditions, dealing with arctic or desert temperature, humidity, water, dust, dirt, shock, vibration or even crash.
Whether you are testing passenger cars, commercial vehicles, military vehicles, or trains, each vehicle places special demands on field testing and requires testing in line with the target application, validating the attributes of the products.

RLDA as a testing method is executed mainly on test tracks in proving grounds and measures vehicle response to typical load cases. It includes essential vehicle and driving parameters, such as mass, inertia, rolling resistance, road characteristics, and vehicle speed. Typical tracks to measure the load are Belgian pavé, axle bumps, sine waves, rough tracks, ramps, gravel pits, and many more variants. RLDA is part of the overall structural integrity process of a program.

Powertrain, transmission, and overall drivetrain performance testing is still part of mobile testing campaigns. In scope are tests of acceleration 0 – 100 km/h running on straight tracks, high-speed ovals, or hill tracks. To analyse the overall efficiency of vehicles, everyday driving conditions are tested in true field trials meeting the Worldwide Harmonised Light Vehicle Test Procedure (WLTP). These trials include all measurements along the propulsion from energy source to road, plus other supporting data sources.

After completing vehicle development, the vehicle is subjected to a so-called endurance test, one of the final vehicle development steps before a vehicle is approved for mass production, ensuring high-quality standards, legal demands, and customer satisfaction. During the endurance testing phase, a fleet of vehicles is driven in a multitude of different driving profiles in different testing locations all around the world, on both public roads and proving grounds.

Vehicle test programs often include durability and performance tests in extreme weather conditions, from cold land winter tests to hot land summer tests in deserts. Even under such conditions, all vehicles must operate safely and smoothly.

Winter: Durability and drivability tests on icy roads, through snow, and in temperatures down to –40°C. Programs include cold start testing of powertrains, heat ventilation and automatic climate control system (HVAC) validation. Tyres get a special focus according to FMVSS, ASTM, SAE, and ISO standards.
The installed DAQ equipment often stays outside in the completely frozen vehicle and shortly after start-up it runs through the dew point without any major effect in measurement results.

Summer: The durability and performance of the complete vehicle, its powertrain, HVAC and many other parts is tested under extreme hot temperatures up to 50°C, including off-road and sand driving capability.
The DAQ equipment is often installed next to the propulsion and needs to deal with high ambient heat going up to 80°C apart from device self-heating stressing the overall measurement job.