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A description is provided detailing the results of the quality function deployment process used to identify customer needs and requirements. Through this process two primary project goals were developed consisting of integrating an electrical-solenoid actuated device into existing space constraints and providing cost reduction alternatives. A static and dynamic analysis was initially required to find the boundary conditions of the external forces imposed on the existing pneumatic device while being subjected to multiple pallets impacting the stop block assembly. Further static analysis was conducted to find the internal forces imposed on the stop arm subassembly in order to properly size the electrical solenoid. Subsequent research into various solenoids led to two solenoid manufacturers evaluated by means of a design evaluation matrix.

Controlling the Cost of Variance is essential to the manufacturing process of Printed Circuit Board Assembly for low volume high mix production. The material variance is identified as the additional components and resources consumed beyond the minimum required to complete the project. This Quantity Variance occurs at the effects of defects at key steps of the manufacturing process. Such occurrences result in the need to purchase additional components for the completion of the order. These additional components termed Quantity Variance alter the sequence of the manufacturing process affecting quality, timely delivery of the job and directly impacting company profitability.

Fouling spark plugs on an internal combustion engine is greatly influenced by cold temperatures, especially at older assembly plants where the vehicle is moved several times because of discontinuities in the assembly line. To transition the vehicle, the operator starts the vehicle, places it in drive and accelerates rapidly, then shuts the vehicle off. This process only lasts ten to fifteen seconds and does not allow the spark plug or engine to get to a high enough operating temperature to evaporate away the fuel, which fouls the spark plugs. A spark plug fouling test is devised and is used to investigate which properties of fuel play the most significant anti-fouling role. Some additives believed to have anti-fouling properties will also be investigated to determine their significance. The anti-fouling fuel will then be implemented at the assembly plants.

A unique differential assembly was needed for the Lawrence Technological University (LTU) SAE Formula race car. Specifically, a differential was required that had torque sensing capabilities, perfect reliability, high strength, light weight, the ability to withstand inertia and shock loading, a small package, no leaks, the ability to support numerous components. In that regard, an existing differential was selected that had the torque sensing capabilities, but had deficiencies that needed to be fixed. Those deficiencies included the following: Differential unit was over 4 kg unmounted, with no housing. This was considered too heavy, when housed properly. Bearing surface was provided on only one end of the carrier. This design provides insufficient bearing surface to support either the differential housing or half-shafts The internal drive splines integral to the case are not optimized for a perpendicular drive/axle arrangement, such as, a chain drive.

Control of annoying noises such as buzzes, squeaks and rattles (BSRs) is particularly important for complex products such as automobiles. This importance has become even more significant as electric vehicles become more popular, eliminating much of the ambient background vehicle noise. A customer's perception of the durability and solidness of a vehicle is based largely on sensory responses such as sound. Recent advances in beamforming technology have the potential to change the way BSR audits and vehicle development testing are done. This paper introduces the application of spherical beamforming technology to BSR testing and provides test results showing the localization accuracy of a rigid spherical array system in a vehicle cabin.

To stay competitive, new products require faster development time at low cost and good quality. Defense as well as commercial industries are forced to use analytical tools to stay competitive in a tough market. The use of simulation tools and approximation techniques in evaluating product performance during the early stages of the product development has a major impart on the product development efficiency, effectiveness, and lead time. Building physical prototypes of complex systems is expensive and it is difficult and time consuming to develop them. It is extremely beneficial to know as much as possible about the product performance and to optimize its dynamic characteristics before the first physical prototype is built.

There are more and more LEDs being used in an automobile to replace the incandescent lamps. All those applications require high brightness LED work at high ambient temperature. However, the luminous flux output of a LED is directly related to its junction temperature. Higher the LED junction temperature, lower the luminous output from the LED. In order to efficiently apply LED to an automotive application the temperature effects on luminous flux must be accounted for in any design of a LED assembly. A LED junction temperature measurement system is described in this paper to measure the differential junction temperature between a reference LED and the LED under test. And the results are used to improve the LED assembly design.

All-wheel drive (AWD) vehicle performance considerably depends not only on total power amount needed for the vehicle motion in the given road/off-road conditions but also on the total power distribution among the drive wheels. In turn, this distribution is largely determined by the driveline system and its mechanisms installed in power dividing units. They are interwheel, interaxle reduction gears, and transfer cases. The paper presents analytical methods to evaluate the energy and, accordingly, fuel efficiency of vehicles with any arbitrary number of the drive wheels. The methods are based on vehicle power balance equations analysis and give formulas that functionally link the wheel circumferential forces with slip coefficients and other forces acting onto an AWD vehicle. The proposed methods take into consideration operational modes of vehicles that are tractive mode, load transportation, or a combination of both.

The 2000 Formula SAE Team at Lawrence Technological University (LTU) has designed a chain driven, three-piece aluminum differential unique from past years. This innovative design introduces an adjustable chain mount replacing conventional shackles. Made completely of aluminum, this device moves the entire rear drive train. The gear set remains to be limited slip with a student designed housing. The idea of an aluminum housing with manufactured gear set is a continued project at LTU. After cutting approximately 33% from the weight of the 1999 differential, the 2000 is geared toward a simpler, and smaller design, easier assembly and lighter weight. After reading this brief overview, the idea of this paper is to provide an understanding of the reasoning behind the choices made on the LTU driveline team. FIGURE 1

An ergonomics study was conducted in a mock-up with a fixed steering wheel position. Drivers adjusted the seat and pedals to a comfortable position. A three-dimensional coordinate measurement machine (CMM) was used to measure the comfortable position of 21 participants. Proven test methods were used to collect the posture data. A model is described to assist in seat and pedal placement for cockpit design.

A vehicle’s exterior fit and finish, in general, is the first system to attract customers. Automotive exterior engineers were motivated in the past few years to increase their focus on how to optimize the vehicle’s exterior panels split lines quality and how to minimize variation in fit and finish addressing customer and market required quality standards. The design engineering’s focus is to control the deviation from nominal build objective and minimize it. The fitting process follows an optimization model with the exterior panel’s location and orientation factors as independent variables. This research focuses on addressing the source of variation “contributed factors” that will impact the quality of the fit and finish. These critical factors could be resulted from the design process, product process, or an assembly process. An empirical analysis will be used to minimize the fit and finish deviation.

The dynamics of an AWD vehicle is determined by the interactions between the vehicle's wheels and the tire contact surface. Understanding and controlling these interactions drives the vehicle mobility and energy efficiency. In this paper new issues related to tire slippage control are addressed. The paper analytically demonstrates that two tires on the same axle with the same rotational speeds can have different slippages when the normal reaction and inflation pressure vary due to motion conditions. Hence, a new method is proposed to control the rotational velocity of the wheels in a way that provides the same slippages of the tires by accounting for changes in the normal load and tire inflation pressure. This approach is especially beneficial for vehicles with individual (electric) wheel drives which can be individually controlled by introducing the proposed algorithm for controlling both the vehicle linear velocity and the tire slippages.

To evaluate traction and velocity performance and other operational properties of a vehicle requires data on some tire parameters including the effective rolling radius in the driven mode (no torque on a wheel), the effective radii in the drive mode (torque applied to the wheel), and also the tire longitudinal elasticity. When one evaluates vehicle performance, these parameters are extremely important for linking kinematic parameters (linear velocity and tire slip coefficient) with dynamic parameters (torque and traction net force) of a tired wheel. This paper presents an experimental method to determine the above tire parameters in laboratory facilities. The facilities include Lawrence Technological University's 4x4 vehicle dynamometer with individual control of each of the four wheels, Kistler RoaDyn® wheel force sensors that can measure three forces and three moments on a wheel, and a modern data acquisition system. The experimental data are also presented in the paper.

The 1999 Lawrence Technological University (LTU) drive train consists of a sprocket and chain assembly that delivers the torque, developed by a 600cc Honda F3 engine, to the rear wheels. The torque is transferred through a limited-slip, torque sensing differential unit comprised of a gear set in a student designed housing. The 1999 differential is a second-generation aluminum housing. The idea of using aluminum was first attempted with the 1998 team who successfully completed and used aluminum despite much complexity and a few design flaws. Therefore, in the LTU Formula Team's continuing effort to optimize the design, a new less complex design was conceived to house the gear set. This innovative design reduces the number of housing components from three in 1998, to two in 1999.

Traction control is an electronic means of reducing the wheel spin caused by the application of excessive power for the valuable grip. Wheel spin can result in loss control of the car, reduce acceleration and cause tire wear. In the front wheel tire the loss grip is experienced as underwater, where the front of the car ‘pushes’ forward, not turning as much as the driver has exposed by turning the tearing. In the rear wheels slip causing oversteer, where the rear of the car swings around, turning much sharper than the driver anticipated. The result of all these problems is that the driver starts loosing control of the vehicle, which is undesirable. With the new design of the Traction Control System, the amount of the wheel slippage is precisely controlled. In racing, this means corner can be taken constantly quicker, with system applying the maximum power possible while the driver remains in total control.

Formula SAE is a Student project that involves a complete design and fabrication of an open wheel formula-style racecar. This paper will cover the suspension geometry and its components, which include the control arm, uprights, spindles, hubs, and pullrods. The 2002 Lawrence Technological Universities Formula SAE car will be used as an example throughout this paper.

Lawrence Technological University's 1998 SAE Formula car needed a high performance differential assembly. The performance requirements of a competitive SAE Formula car differential are as follows: Torque sensing capabilities Perfect reliability High strength Low mass Ability to withstand inertia and shock loading Small package Leak proof housing Ability to support numerous components With these requirements in mind an existing differential was selected with the capability for torque sensing. This differential lacked the desired low mass, support, internal drive splines, and proper gearing protection. The differential was re-engineered to remedy the deficiencies. The internal gearing from the selected differential was used in an improved casing. This casing and it's position in the car, reduce the number of side-specific parts required as well as improving the performance. The new design significantly reduces the size and mass of the assembly.

The purpose of this paper is to present the design and assembly of a working prototype of an alternate fueled lawnmower. A variety of alternate fuels have been suggested to help reduce air quality problems. The conversion process from gasoline to Propane will be explained. To determine fuel consumption and developed horsepower, engine simulations were performed. Stoichiometric analysis was performed to determine and compare the products of combustion between Propane and gasoline. The prototype Propane fueled lawnmower is able to operate efficiently and with less emissions as compared with a comparable gasoline fueled lawnmower. Engine output has been reduced by 27%. By burning Propane, a relatively clean fuel, engine emissions have been reduced by 60% as compared to gasoline.

The initiative of this paper is focused on improving the heat dissipation from the pressure wheel of a laser welding assembly in order to achieve a longer period of use. The work examines the effects of different geometrical designs on the thermal performance of pressure wheel assembly during a period of cooling time. Three disc designs were manufactured for testing: Design 1 – a plain wheel, Design 2 – a pierced wheel, and Design 3 – a wheel with ventilating vanes. All of the wheels were made of carbon steel. The transient thermal reaction were compared. The experimental results indicate that the ventilated wheel cools down faster with the convection in the ventilated channels, while the solid plain wheel continues to possess higher temperatures. A comparison among the three different designs indicates that the Design 3 has the best cooling performance.