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This study presents a methodology for comparative analysis of seat and suspension parameters on a system level to achieve minimum occupant head displacement and acceleration, thereby improving occupant ride comfort. A lumped-parameter full-vehicle ride model with seat structures, seat cushions and five occupants has been used. Two different vehicle masses are considered. A low amplitude pulse signal is provided as the road disturbance input. The peak vertical displacement and acceleration of the occupant’s head due to the road disturbance are determined and used as measures of ride comfort. Using a design of experiments approach, the most critical seat cushion, seat structure and suspension parameters and their interactions affecting the occupant head displacement and acceleration are determined. An optimum combination of parameters to achieve minimum peak vertical displacement and acceleration of the occupant’s head is identified using a response surface methodology.

This paper presents results of two surveys, namely, a photographic measurements survey and a rider survey, conducted to determine how the type and origin of a motorcycle related to motorcycle dimensions, rider characteristics, seating posture, and motorcycle controls and displays. In the photographic survey, 12 most popular motorcycles covering three types (cruiser, sport, and touring) and three origins (Europe, Asia and North America) were measured from photographs taken in a standardized procedure with and without a rider. The data showed that the Asian and North American cruisers were very similar in all dimensions. These include seat height, seat to handlebar location, seat to foot rest location, foot rest size, and handgrip stance. This resulted in similar rider posture. North American sport motorcycles were more like cruisers than the Asian and European sport motorcycles.

Semi-trucks, specifically class-8 trucks, have recently become a platform of interest for autonomy systems. Platooning involves multiple trucks following each other in close proximity, with only the lead truck being manually driven and the rest being controlled autonomously. This approach to semi-truck autonomy is easily integrated on existing platforms, reduces delivery times, and reduces greenhouse gas emissions via fuel economy benefits. Level 1 SAE fuel studies were performed on class-8 trucks operating with the Auburn Cooperative Adaptive Cruise Control (CACC) system, and fuel savings up to 10-12% were seen. Enabling platooning autonomy required the use of radar, global positioning systems (GPS), and wireless vehicle-to-vehicle (V2V) communication. Poor measurements and state estimates can lead to incorrect or missing positioning data, which can lead to unnecessary dynamics and finally wasted fuel.

This paper describes a unique interior design and multidisciplinary process implemented by the faculty and students to develop the interior for a Low Mass Vehicle (LMV). The 103 inch LMV was designed with the goal of about 30% reduction in weight than a typical class C segment vehicle and would require low investment in manufacturing. In the early stages of the program, the UM-Dearborn team developed detailed requirements of the vehicle interior based on the vehicle's exterior developed using a similar process. The requirements were given to a senior class of automotive design students from the College of Creative Studies in Detroit to create different interior design themes. Approximately twenty-five interior design themes were judged by a panel of automotive industry experts, and a winning design was selected.

Autonomy for multiple trucks to drive in a fixed-headway platoon formation is achieved by adding precision GPS and V2V communications to a conventional adaptive cruise control (ACC) system. The performance of the Cooperative ACC (CACC) system depends heavily on the reliability of the underlying V2V communications network. Using data recorded on precision-instrumented trucks at both ACM and NCAT test tracks, we provide an understanding of various effects on V2V network performance: Occlusions - non-line-of-sight (NLOS) between the Tx and Rx antenna may cause network signal loss. Rain - water droplets in the air may cause network signal degradation. Antenna position - antennas at higher elevation may have less ground clutter to deal with. RF interference - interference may cause network packet loss. GPS outage - outages caused by tree cover, tunnels, etc. may result in degraded performance. Road curvature - curves may affect antenna diversity.

Based on the theory of damage mechanics, an orthotropic damage model for the prediction of forming limit diagram (FLD) is developed. The conventional method of FLD used to predict localized necking adopts two fundamentally different approaches. Under biaxial loading, the Hill's plasticity method is often chosen when α (= ε2/ε1) < 0. On the other hand, the M-K method is adopted for the prediction of localized necking when α > 0 or the biaxial stretching of sheet metal is pronounced. The M-K method however suffers from the arbitrary selection of the imperfection size, thus resulting in inconsistent predictions. The orthotropic damage model developed for predicting the FLD is based on the anisotropic damage model recently proposed by Chow et al (1993). The model is extended to take into account, during the sheet forming process, orthotropic plasticity and damage. The orthotropic FLD model consists of the constitutive equations of elasticity and plasticity coupled with damage.

Seat comfort is a highly subjective attribute and depends on a wide range of factors, but the successful prediction of seat comfort from a group of relevant variables can hold the promise of eliminating the need for time-consuming subjective evaluations during the early stages of seat cushion selection and development. This research presents the subjective seat comfort data of a group of 30 participants using a controlled range of seat foam samples, and attempts to correlate this attribute with a) the anthropometric and demographic characteristics of the participants, b) the objective pressure distribution at the body-seat interface and c) properties of the various foam samples that were used for the test.

This paper presents results of a five phase study conducted to evaluate touch feel and appearance of door armrest materials. Seven different production door armrests with different material characteristics such as softness, smoothness, compressibility, texture, etc. were evaluated. In the first phase, the subjects seated in a vehicle buck in their preferred seating position with the armrests adjusted at their preferred heights, provided ratings on a number of touch feel and appearance of the door armrest materials using 5-point semantic differential scales. In the second phase, the armrests were presented to each subject in all possible pairs and they were asked to select preferred armrest material in each pair.