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The helical spring is one of fundamental mechanical elements used in various industrial applications such as valves, suspension mechanisms, shock and vibration absorbers, hand levers, etc. In high speed applications, for instance in the internal combustion engine or in reciprocating compressor valves, helical springs are subjected to dynamic and impact loading, which can result in a phenomenon called “surge”. Hence, proper design and selection of helical springs should consider modeling the dynamic and impact response. In order to correctly characterize the physics of a helical spring and its response to dynamic excitations, a comprehensive model of spring elasticity for various spring coil and wire geometries, spring inertial effects as well as contacts between the windings leading to a non-linear spring force behavior is required. In practical applications, such models are utilized in parametric design and optimization studies.

We present research in progress to develop and implement a transportable instrumentation package (TIP) to collect driver data in a vehicle. The overall objective of the project is to investigate the symbiotic relationship between humans and their vehicles. We first describe the state-of-art technologies to build the components of TIP that meet the criteria of ease of installation, minimal interference with driving, and sufficient signals to monitor driver state and condition. This method is a viable alternative to current practice which is to first develop a fully instrumented test vehicle, often at great expense, and use it to collect data from each participant as he/she drives a prescribed route. Another practice, as for example currently being used in the SHRP-2 naturalistic driving study, is to install the appropriate instrumentation for data collection in each individual's vehicle, often requiring several hours.

Analyses were performed to determine the sensitivity of stopping sight distance on vertical curves to driver eye height and other parameters entering into the stopping sight-distance equations. Sight distance was found to be relatively insensitive to eye height. On a given hill crest, sight distance for a driver whose eye height is 6-inches lower than the design eye height (3.75 ft) is only 5% less than the design sight distance. On the other hand, stopping distance is very sensitive to travel speed, pavement friction and reaction time. For example, a 1.8 mph decrease in speed reduces stopping distance by the same amount that a 6-inch decrease in eye height reduces sight distance. Also, sight distance is about 2.5 times more sensitive to obstacle height than eye height. It is argued that reductions in travel speed since the introduction of the 55-mph speed limit compensate for any recent or projected decreases in driver eye height.

Noise generating mechanisms connected with steel-blanking operation has been identified and their engineering treatments developed and tested. Use of rubber-metal laminates proved to be successful for cushioning impacts in kinematic pairs and joints. Use of plastic for the stripper plate construction was recommended. The “die stiffener” concept was developed to reduce main noise peak associated with punch breakthrough. Screening of the die cavity by a transparent curtain of overlapping PVC strips was shown to be effective. A pulse load simulator with adjustable load rate and amplitude has been developed to facilitate testing of presses.

A new inflator specification, the “inflator thrust variable,” was developed to better explain measured mid-sized male, instrumented test dummy responses in the chest-on-module test condition. Specifically, controlled laboratory experiments were conducted with non-production, driver airbag modules with inflators of various outputs and gas constituents in an effort to assess their effects on a pertinent occupant response. Regression analyses showed that the inflator thrust variable is a better predictor of the observed variation in peak viscous criterion responses than either peak tank pressure or the related pressure rise rate when inflators of differing gas composition were compared.

This paper presents real-world driving energy and fuel consumption results for the second-generation Chevrolet Volt plug-in hybrid electric vehicle (PHEV). A drive cycle, local to Michigan Technological University, was designed to mimic urban and highway driving test cycles in terms of distance, transients and average velocity, but with significant elevation changes to establish an energy intensive real-world driving cycle for assessing potential energy savings for connected and automated vehicle (CAV) control. The investigation began by establishing baseline and repeatability of energy consumption at various battery states of charge. It was determined that drive cycle energy consumption under a randomized set of boundary conditions varied within 3.6% of mean energy consumption regardless of initial battery state of charge.

Reductions of hardware costs as well as implementations of new innovative functions are the main drivers of today's automotive electronics. Indeed more and more resources are spent on adapting existing solutions to different environments. At the same time, due to the increasing number of networked components, a level of complexity has been reached which is difficult to handle using traditional development processes. The automotive industry addresses this problem through a paradigm shift from a hardware-, component-driven to a requirement- and function-driven development process, and a stringent standardization of infrastructure elements. One central standardization initiative is the AUTomotive Open System ARchitecture (AUTOSAR). AUTOSAR was founded in 2003 by major OEMs and Tier1 suppliers and now includes a large number of automotive, electronics, semiconductor, hard- and software companies.

Lower limb injury is becoming an increasingly important concern in vehicle safety for both occupants and pedestrians. To enable vehicle manufacturers to better understand the biomechanical effects of design changes, it is deemed beneficial to employ a biomechanically fidelic finite element model of the human lower limb. The model developed in this study includes long bones (tibia, fibula, femur) and flat bone (patella) as deformable bodies. The pelvis and foot bones are modeled as rigid bodies connected to the femur and tibia/fibula via rotational spring-dashpots. The knee is defined by scanned bone surface geometry and is surrounded by the menisci, major ligaments, and patellar tendon. Finite elements used to model include 6- and 8-node solids for cartilage, menisci, surrounding muscles, and cancellous bone; 3- and 4-node shells for skin and cortical bone; and nonlinear spring-dashpots for ligaments.

This paper will discuss the various tools used to measure the steering and suspension properties of a vehicle. Measuring the kinematic and compliance properties of the steering and suspension systems is an important part of the vehicle development process. Some of the ways these measurements are used include confirmation of vehicle design and build, to create and correlate CAE models, and for diagnosis of steering and handling concerns. Understanding exactly how the steering and suspension systems are performing is an important step in the development process. We have found that by employing the proper tools and methods, plus having a defined vehicle dynamics fingerprint process, that most issues and concerns can be successfully resolved.