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Leak detection of vehicle cabin interiors is an important quality inspection phase that typically has been handled with various time consuming, or potentially product damaging techniques. Leak detection in tank or pressure vessel applications is almost always a concern for gas or fluid containment in vehicles and in many other industries. Numerous techniques exist for the detection of leaks in these and other types of structures. When testing is required in a production environment, often the speed of leak detection is very important if all samples must be tested. The use of several ultrasound based methods for leak detection in vehicle cabins and pressure vessel applications is presented here. Ultrasound waves are typically classified as having spectral content greater than 20 kHz. In the case of leak detection in a production environment, frequently the ultrasonic spectrum is largely free from background noise content that dominates the audible spectrum.

With the amount of adjustability present in today's automotive seat, it is a given that some form of looseness and free-play will exist in the structure. The automotive seat community is commonly faced with free-play issues; this is a significant issue where modal analysis is concerned. Free-play creates a non-linear situation, causing a violation of the linear mathematics that modal analysis is based on. Obviously, this situation is not the ideal circumstances under which to perform modal testing and analysis, but 99.9% of the time, the receipt of better samples (reduced free-play) is not a likely option, and the test must still go on. Ideally, you would want to test this structure using random excitation with a shaker to minimize the nonlinearities and provide a repeatable input force.

Measuring and modeling parasitic losses in driveline components continues to be an important topic in product development. There are existing standards (SAE J2985 [1], J3039[2], and J3218[3]) for measuring and reporting spin loss parasitic losses. All these tests are conducted at fixed temperatures of 28°C and 65°C with a variety of controls and measurement positions to ensure these conditions. The limitation of these methods is that they do not represent the actual vehicle range of operating temperatures. In 2020, Guarino et al presented the paper SAE 2020-01-1413 [4] on development of a test method for beam axles (which was developed into SAE J3218). In the paper, a floating temperature sweep test method was developed for testing efficiency over a range of temperature at a fixed operating condition. This paper will highlight adapting the efficiency floating temperature sweep test method and applying it to spin loss measurement (a transfer case was used in this development).