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During the initial vehicle design phase and as the first prototypes are built, extensive on-board instrumentation and data acquisition is required at the proving grounds (PG). The data is used for various types of testing and analysis. During this phase of development very few parts and assembly components are available for physical test. The objective is to develop a component test for the truck box. This test can be run without suspension parts during the early stages of the vehicle development. A further objective is to correlate the test to FEA models and actual Proving Ground full vehicle test results.

Based on the results of “An Evaluation of the Mechanical Properties of Wheel Force Sensors and their Impact on to the Data Collected During Different Driving Manoeuvres” Herrmann et al. (SAE Paper 05M-254) a second, detailed investigation has been started to acquire additional information. In this previous investigation, it has been found out, that a difference in mass can be clearly identified in the signals. The current paper summarizes the results of a detailed investigation, which has been performed at DaimlerChrysler Stress Lab in Auburn Hills, with a fully equipped vehicle - a set of 2/4 Wheel Force Sensors plus several acceleration sensors as well. Through careful research and testing it is expected that the differences in the dynamic behavior can be specified with better accuracy than in the previous study.

In this paper, responses from a vehicle's suspension, chassis and body, are used to demonstrate a methodology to optimize physical test results. It is well known that there is a variability effect due to an increase of wheel unsprung mass (due to loads measurement fixturing), tire pressure, speed, etc. This paper quantifies loading variability due to Wheel Force Transducer (WFT) unsprung mass by using a rainflow cycle counting domain. Also, presents a proving ground-to-test correlation study and the data reduction techniques that are used in road simulation test development to identify the most nominal road load measurement. Fundamental technical information and analytical methodology useful in overall vehicle durability testing are discussed. Durability testing in a laboratory is designed to correlate fatigue damage rig to road. A Proving Ground (PG) loading history is often acquired by running an instrumented vehicle over one or more PG events with various drivers.