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Original equipment manufacturers and their customers are demanding more efficient, lighter, smaller, safer, and smarter systems across the entire product line. In the realm of automotive, agricultural, construction, and earth-moving equipment industries, an additional highly desired feature that has been steadily trending is the capability to offer remote and autonomous operation. With the previous requirements in mind, the authors have proposed and validated a new electrohydraulic steering technology that offers energy efficiency improvement, increased productivity, enhanced safety, and adaptability to operating conditions. In this paper, the authors investigate the new steering technology's capacity to support remote operation and demonstrate it on a compact wheel loader, which can be remotely controlled without an operator present behind the steering wheel. This result establishes the new steer-by-wire technology's capability to enable full autonomous operation as well.

This research provides a capacitance based method for monitoring the integrity of tires and other polymeric products during manufacturing and throughout the useful product life. Tire and wheel failures and tire degradation were the reported cause for approximately 19320 vehicle crashes over a two and a half year period according to the U.S. Department of Transportation National Highway Traffic Safety Administration's 2008 survey. Tires are complex composite structures composed of layers of formulated cross-linked rubber, textiles, and steel reinforcement layers. Tire production requires precise manufacturing through chemical and mechanical methods to achieve secure attachment of all layers. Tires are subjected to a variety of harsh environments, experience heavy loads, intense wear, heat, and in many cases lack of maintenance. These conditions make tires extremely susceptible to damage.

The lack of effective and efficient communication between pilots and maintenance technicians has been recognized as a problem in general aviation by both members of the industry and academia. The goal of this paper is to provide an accounting of the impact that communication between maintenance technicians and pilots, or the lack thereof, can have upon both the bottom line and the experience of those who operate within the general aviation arena. The researchers interviewed and observed maintenance technicians and pilots in general aviation operations to identify what members on both sides of the communication process identified as being problematic and troubling. Several of the major barriers to communication, as well as several strategies to overcome those barriers, are discussed.

The energy finite element method (EFEM) was developed to utilize available finite element geometric models for high frequency structural-acoustic analysis. Statistical Energy Analysis (SEA) is a lumped parameter approach currently in widespread use for high frequency analysis. In this investigation, EFEM and SEA models were developed for components of a heavy equipment cab. A generalized joint process (GJP) was developed and used for processing the various joints between structural subsystems. The structural predictions were compared to each other as well as to measurements.

Most airline maintenance human factors training programs miss the mark when it comes to producing optimal behavioral and procedural changes among participating maintenance professionals. While there are many causes for training outcomes which are less than desired and anticipated, principal among these are the failure of most programs to address the pragmatic learning needs of those technicians as adult learners. Attention to andragogical principles such as clear learning goals, readily apparent relevance and direct applicability of material, immediate feedback, learner directed inquiry and self assessment can contribute greatly to achieving optimal results. A program currently under development at Purdue University utilizes a combination of classroom instruction, group discussion, and learner participation in aviation maintenance scenarios as a method for improving human factors education.

A new laboratory method has been developed to evaluate the acoustical properties of expandable and other automotive sealants. These materials are used to reduce wind, road, and powertrain noise transmission into passenger compartments. In the new method, ASTM E 1050 absorption measurement equipment is used along with a new sample holder, a downstream microphone holder (providing two additional microphone locations) and an anechoic termination. These additions permit measurement of normal incidence transmission loss as well as absorption. It is intended to encourage adoption of this method as a standard way of quantifying the acoustical performance of sealants and sealing composites in automotive noise control applications.

Structural sound transmission through primary bulb (PB) sealing systems was investigated. A two-degrees-of-freedom analytical model was developed to predict the sound transmission characteristics of a PB seal assembly. Detailed sound transmission measurements were made for two different random excitations: acoustic and aerodynamic. A reverberation room method was first used, whereby a seal sample installed within a test fixture was excited by a diffuse sound field. A quiet flow facility was then used to create aerodynamic pressure fluctuations which acted as the excitation. The space-averaged input pressure within the pseudo door gap cavity and the sound pressure transmitted on the quiescent side of the seal were obtained in each case for different cavity dimensions, seal compression, and seal designs. The sound transmission predictions obtained from the lumped element model were found to be in reasonable agreement with measured values.

The flow-induced pressure fluctuations in a door gap cavity model were investigated experimentally using a quiet wind tunnel facility. The cavity cross-section dimensions were typical of road vehicle door cavities, but the span was only 25 cm. One cavity wall included a primary bulb rubber seal. A microphone array was used to measure the cavity pressure field over a range of flow velocities and cavity configurations. It was found that the primary excitation mechanism was an “edge tone” phenomenon. Cavity resonance caused amplification around discrete frequencies, but did not cause the flow disturbances to lock-on. Possible fluid-elastic coupling related to the presence of a compliant wall was not significant. A linear spectral decomposition method was then used to characterize the cavity pressure in the frequency domain, as the product of a source spectral distribution function and an acoustic frequency response function.

Acoustic array techniques are presented as alternatives to intensity measurements for source identification in automotive and industrial environments. With an understanding of the advantages and limitations described here for each of the available methods, a technique which is best suited to the application at hand may be selected. The basic theory of array procedures for Nearfield Acoustical Holography, temporal array techniques, and an Inverse Frequency Response Function technique is given. Implementation for various applications is discussed. Experimental evaluation is provided for tire noise identification.