Janice Tardiff

Magnetorheological elastomers: properties and applications

Magnetorhelogical (MR) elastomers are viscoelastic solids whose mechanical properties are controllable by applied magnetic fields. We have developed a family of MR elastomers, comprising micrometer-sized carbonyl iron particles embedded in natural rubber, that can be processed using conventional rubber-mixing techniques. By crosslinking the elastomer in the presence of an applied magnetic field, field-induced interparticle interactions promote the formation of particle chains and columns aligned along the field direction. The resulting composites possess field- dependent of the mechanical properties of MR elastometers enables the construction of controllable elastomeric components, such as suspension bushings, that may prove advantageous in some automotive applications.

A simplified analysis method for correlating rotary atomizer performance on droplet size and coating appearance

The dominant method of atomizing automotive paint is through the use of rotating bell sprayers. For this class of atomizer, the problem of paint thickness across the bell has been theoretically solved on a representative geometry that includes factors such as fluid flow rate, bell speed, bell cup radius, and fluid properties. It was assumed that the paint film eventually forms uniform ligaments at the bell cup edge that break due to hydrodynamic stability during the paint spray process; thus, creating a characteristic particle size distribution for the spray. These particle size distributions will vary as the spray parameters, specifically fluid flow rate, bell speed, and bell cup radius, vary. The theoretical model that has been developed strongly correlates to the literature data available for paint droplet size from rotary bell atomizers. Expansion of the correlation of the theoretical model to paint appearance wavelength measurements, Wc and Wd, in place of droplet size provides further understanding of the effect of paint spray parameters on paint appearance. Use of these correlations can help to optimize paint appearance and improve paint spray simulation results.

Fuzzy modeling within the statistical process control framework

This paper links the well-known technique of statistical process control (SPC) monitoring to the concept of rule-based fuzzy modeling. A family of if ... then rules with fuzzy predicates describes the set of steady state input-output relationships when the process variations are due to process noise (common causes). The ability of the SPC method to on-line diagnose a change in the distribution of the process variables is used to identify a new operating point of the systems, and consequently the initiation of a new potential rule. The model is applied as a decision support tool to help identify the optimal changes of the inputs associated with the special causes and to minimize the time for their elimination. A case study on automotive paint process optimization that is based on this concept is presented.

Development of an Improved Cosmetic Corrosion Test for Finished Aluminum Autobody Panels

A co-operative program initiated by the Automotive Aluminum Alliance and supported by USAMP continues to pursue the goal of establishing an in-laboratory cosmetic corrosion test for finished aluminum auto body panels that provides a good correlation with in-service performance. The program is organized as a task group within the SAE Automotive Corrosion and Protection (ACAP) Committee. Initially a large reservoir of test materials was established to provide a well-defined and consistent specimen supply for comparing test results. A series of laboratory procedures have been conducted on triplicate samples at separate labs in order to evaluate the reproducibility of the various lab tests. Exposures at OEM test tracks have also been conducted and results of the proving ground tests have been compared to the results in the laboratory tests. Outdoor tests and on-vehicle tests are also in progress. An optical imaging technique is being utilized for evaluation of the corrosion. This paper summarizes the analyses of the results from the laboratory tests and the OEM test track exposures.

Using smart materials to solve new challenges in the automotive industry

Ford has an extensive history of developing and utilizing smart and innovative materials in its vehicles. In this paper, we present new challenges the automotive industry is facing and explore how intelligent uses of smart materials can help provide solutions. We explore which vehicle attributes may provide most advantageous for the use smart materials, and discuss how smart material have had technical challenges that limit their use. We also look at how smart materials such as gecko inspired adhesion is providing opportunities during the vehicle assembly process by improving manufacturing quality, environmental sustainability, and worker safety. An emerging area for deployment of smart materials may involve autonomous vehicles and mobility solutions, where customer expectations are migrating toward a seamless and adaptive experience leading to new expectations for an enhanced journey. Another area where smart materials are influencing change is interior and exterior design including smart textiles, photochromatic dyes, and thermochromatic materials. The key to advancing smart materials in automotive industry is to capitalize on the smaller niche applications where there will be an advantage over traditional methods. Ford has an extensive history of developing and utilizing smart and innovative materials. Magnetorheological fluids, thermoelectric materials, piezoelectric actuators, and shape memory alloys are all in production. In this paper we present new challenges the automotive industry is facing and explore how intelligent uses of smart materials can help provide solutions. We explore which vehicle attributes may provide most advantageous for the use smart materials, and discuss how smart materials have had technical challenges that limit their use. An emerging area for deployment of smart materials may involve autonomous vehicles and mobility solutions, where customer expectations may require a seamless and adaptive experience for users having various expectations.