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Moir� method is useful to measure the shape and the whole-field distributions of displacement and strain of structures. There are many kinds of moir� methods such as geometric moir� method, sampling moir� method, Fourier transform moir� method, moir� interferometry, shadow moir� method and moir� topography. Grating method analyzing directly deformation of a grating without any moir� fringe pattern is considered as an extended technique of moire method. Phase analysis of the moire fringe patterns and the grating patterns provides accurate measurements of shapes or displacement and strain distributions. Some applications of these moir� methods and grating methods to dynamic shape and strain distribution measurements of a rotating tire, sub-millimeter displacement measurements from long distance for landslide prediction, real-time shape measurements with micro-meter order accuracy, etc. are shown. Presenter Yoshiharu Morimoto, Moire Institute Inc.

Virtual testing is a method that simulates lab testing using multi-body dynamic analysis software. The main advantages of this approach include that the design can be evaluated before a prototype is available and virtual testing results can be easily validated by subsequent physical testing. The disadvantage is that accurate specimen models are sometimes hard to obtain since nonlinear components such as tires, bushings, dampers, and engine mounts are hard to model. Therefore, virtual testing accuracy varies significantly. The typical virtual rigs include tire and spindle coupled test rigs for full vehicle tests and multi-axis shaker tables for component tests. Hybrid simulation combines physical and virtual components, inputs and constraints to create a composite simulation system. Hybrid simulation enables the hard to model components to be tested in the lab.

In the automotive industry, there is a continued need to improve the development process and handle the increasing complexity of the overall vehicle system. One major step in this process is a comprehensive and complementary approach to both simulation and testing. Knowledge of the overall dynamic vehicle behavior is becoming increasingly important for the development of new control concepts such as integrated vehicle dynamics control aiming to improve handling quality and ride comfort. However, with current well-established test systems, only separated and isolated aspects of vehicle dynamics can be evaluated. To address these challenges and further merge the link between simulation and testing, the Institute of Internal Combustion Engines and Automotive Engineering (IVK), University of Stuttgart is introducing a new Handling Roadway (HRW) Test System in cooperation with The Research Institute of Automotive Engineering and Vehicle Engines Stuttgart (FKFS) and MTS Systems Corporation.

A test engineer faces a series of considerations (decisions) when designing a test program to conduct service history simulation testing of full scale vehicles (structures) in the laboratory. This paper proposes a logical decision path, with pertinent discussion of tradeoffs, which is intended to serve as a design guide in this process. A good deal of the authors’ subjective opinion is included. The paper begins by presenting a model of how a test facility should interface to the total engineering process. This is important in establishing a proper division of responsibility for the validity and usefulness of test results. This is followed by a specific discussion of service history simulation testing for durability evaluation.

ADAMS, SIMULINK, and ADAMS-SIMULINK co-simulation models of component test systems, Multi-Axis-Simulation-Table (MAST) systems, and spindle-coupled vehicle testing system (MTS 329) were created. In the ADAMS models, the mechanical parts, joints, and bushings were modeled. Hydraulic and control elements were absent. The SIMULINK models modeled control and hydraulic elements including actuator dynamics, servo valve dynamics, closed loop control, three-variable control, matrix control, and coordinate transformation. However, the specimen had to be simplified due to the limitation of SIMULINK software. The ADAMS-SIMULINK co-simulation models considered hydraulic and control components in the SIMULINK portion and mechanical components in ADAMS portion. The interaction between the ADAMS and SIMULINK portions was achieved using ADAMS/Control.

Hybrid vehicle simulation methods combine physical test articles (vehicles, suspensions, etc.) with complementary virtual vehicle components and virtual road and driver inputs to simulate the actual vehicle operating environment. Using appropriate components, hybrid simulation offers the possibility to develop more accurate physical tests earlier, and at lower cost, than possible with conventional test methods. MTS Systems has developed Hybrid System Response Convergence (HSRC), a hybrid simulation method that can utilize existing durability test systems and detailed non-real-time virtual component models to create an accurate full-vehicle simulation test without requiring road load data acquisition. MTS Systems and Audi AG have recently completed a joint evaluation project for the HSRC hybrid simulation method using an MTS 329 road simulator at the Audi facility in Ingolstadt, Germany.

The value of crash simulation has long been recognized by carmakers as an essential tool for vehicle development and certification programs. Driven by the need to minimize time-to-market for new models, cost reduction, and by consumer demand for safer cars and trucks, the industry is moving to newer technologies in crash simulation. Crash simulation provides an inexpensive means to quickly simulate the effects of a barrier crash by reproducing its basic elements - acceleration, velocity and displacement - in a nondestructive test. Crash event timing and accuracy of reproduction are critical performance factors. This paper describes the unique features and capabilities offered by a new generation of crash simulators.

Wheel force and moment transducers (WFT) are widely used in vehicle testing and analysis [1], [2], [3]. There are many benefits of using these sensors. To install the transducer, vehicle wheel has to be modified. Transducer mounting adaptors are required to interface the sensor with the modified wheel rim. To study the effect of added mass with wheel force transducers, three vehicles, two types of passenger cars, and one SUV, were instrumented with an MTS spindle wheel force transducer (SWIFT 30A) as well as with regular wheels. The instrumented vehicles were driven on multiple proving ground surfaces with three passes for each vehicle. This experimental data was analyzed using RPC Pro software to assess both per pass variation and data trends from 3 passes without WFT (baseline) and 3 passes with WFT added mass. A validated ADAMS model of a production passenger vehicle, with and without added weight of the wheel force transducers, was also used to assess the added weight effect.

The typical approach for body load simulation during 7-Post testing has been to match body motion and forces for a known suspension setup condition, and then to maintain the applied body loads for subsequent tests with different setups. However, in order for the test to remain valid across a wide range of vehicle setups, the applied body loads may need to be varied to match the specific test car. A significant component of the body load comes from aerodynamic downforce, which can be calculated during a 7-Post test based on vehicle body position and previously recorded wind tunnel test data. This paper discusses a method to generalize the 7-Post inputs by updating the aerodynamic force content automatically during each test run. The paper begins by discussing validation of an active aerodynamic force control scheme on a MTS 320 7-Post road simulator with a NASCAR Sprint Cup vehicle.

5 belt wind tunnels are the most common facility to conduct the experimental aerodynamics development for production cars. Among aerodynamic properties, usually drag is the most important development target, but lift force and its front/rear balance is also important for vehicle dynamics. Related to the lift measurement, it is known that the “pad correction”, the correction in the lift measurement values for the undesirable aerodynamic force acting on wheel belt surface around the tire contact patch, must be accounted. Due to the pad correction measurement difficulties, it is common to simply subtract a fixed amount of lift values from measured lift force. However, this method is obviously not perfect as the pad corrections are different for differing vehicle body shapes, aerodynamic configurations, tire sizes and shapes.

Recently, the use of laboratory-based physical prototype testing as well as the design of virtual models and virtual test equipment has accelerated the pace and quality of racing vehicle development. In particular, the combined use of both virtual and physical testing, when correlated to racetrack improvements, yields a powerful development tool(1), (2),(3). In this study, we applied these techniques from the first stages of the design of a unique Grand Prix racing motorcycle. First, a wire-frame CAD model, then a parametric CAD solid model of the motorcycle was created after preliminary calculations specified the approximate design of structural elements. Subsequently, a virtual dynamic model was created and subjected to a variety of inputs, including sine sweeps, shaped white noise and simulated road time-histories. Loads and other dynamic responses were measured on the virtual model, so that it's design could then be optimized to yield acceptable performance and durability.

Two-poster rig plays a very important role in accelerated durability evaluation in a motorcycle industry, similar to what a four-poster rig does in a car industry. The rig simulates the exact road conditions in the vertical direction through tire coupling by applying feedback control on displacement. On account of its ability to simulate to the exact customer usage conditions, it reproduces the failures realistically as it happens on the field. However, as complete vehicle is required for testing on the rig, the testing happens mostly in the advanced stages of product development. Any failures beyond the concept stage have a huge impact on the development time and cost and the same should be avoided. Therefore, in this paper, a virtual testing methodology is proposed, based on which potential failures on the vehicles can be captured at the concept design stage itself. An ADAMS model of a motorcycle was created.