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A vehicle-level data acquisition (DAQ) system was developed and implemented on the Lawrence Technological University (LTU) Baja SAE vehicle. This low-cost Arduino-based DAQ system is capable of accurately and repeatedly measuring Baja SAE specific vehicle parameters and storing them for offline analysis. While expandable for the needs of future teams, the developed DAQ system includes measurement of vehicle wheel speed, CVT pulley speeds, suspension position, CVT belt temperature, steering load, and steering angle. The development of the DAQ system architecture and the development of the angular speed and suspension position measurement subsystems are the focus of this work. The processes followed and lessons learned can be used by other Baja SAE and SAE Collegiate Design Series. Each measurement subsystem was designed, fabricated, integrated, and validated on the bench and in-vehicle.

Designing a centrifugal pump impeller comes with challenges due to multiple parameters that affect the pump efficiency. A high velocity gradient exists in the flow between the impeller shroud and sidewall of the pump casing due to one surface stationary and the other moving at a high velocity. The internal rotating flow in the impeller shroud-sidewall gap is a major problem that leads to a decrease in pump performance. This study presents a design modification of the gap between the impeller shroud and the pump casing sidewall using an idler disk located in between, which rotates freely during pump operation. In this paper, a numerical analysis was performed to investigate the idler disk's effect on the pump performance for different volumetric flow rate values and idler disk geometries. ANSYS-2019-R1 was used (FLUENT solver) to carry out the computational fluid dynamics (CFD) analysis for evaluating the performance of the baseline and modified designs in a centrifugal pump.

Mechanical engineering students at Lawrence Technological University complete a five-credit hour capstone project: either an SAE collegiate design series (CDS) vehicle or an industry-sponsored project (ISP). Students who select the SAE CDS option enroll in a three-semester, three-course sequence. Each team of seniors designs, builds, and competes with their vehicle at one of the SAE CDS events. Three years after implementing major changes to the course structure and content, the three-semester capstone design sequence is revisited. Finalized learning objectives are presented and the sequence is assessed with a mix of direct, indirect, and anecdotal assessment. Student performance, as measured directly with design reports, milestones, and project completion, is good. Of the five Lawrence Tech CDS teams, only one has failed to be ready for competition since the changes were implemented.

Longitudinal vortex generation is a common technique for enhancing heat transfer performance. It can be achieved by employing small flow manipulators, known as vortex generators (VGs), which are placed on the heat-transfer surface. The vortex generators can generate longitudinal vortices, which strongly disturb the flow structure, and have a significant influence on the velocity and temperature distributions, causing improved thermal transport. In this work, numerical simulations are conducted for a horizontal rectangular channel with and without a pair of longitudinal vortex generators. The vortex generators are fitted vertically on the bottom surface of the channel. The Computational Fluid Dynamics (CFD) analysis aims to acquire a better understanding of the flow structure and heat transfer mechanisms induced by longitudinal vortex generation. The simulation is performed using ANSYS Fluent, and three flow inlet velocities are considered: 1.38 m/s, 1.18 m/s, 0.98 m/s.

Strict regulations exist in different countries with respect to vehicular emissions by their respective government bodies requiring automakers to design fuel-efficient vehicles. Fuel economy and carbon emission are the main factors affecting these regulations. In this competitive industry to make fuel efficient vehicles and reduce Green House Gas (GHG) emissions in internal combustions has led to various developments. Exhaust Heat Recovery System (EHRS) plays a vital role in improving powertrain efficiency. In this system, heat rejected by the engine is reused to heat the vehicle fluids faster (for example, engine coolant, engine oil, etc.) correspondingly reducing harmful gas emissions. In internal combustion engines, generally only 25% of the fuel energy is converted into useful power output and approximately 40% of it is lost in exhaust heat. Certain studies show that by using the EHRS, the power output can be increased to 40% and the heat loss can be reduced to as much as 25%.

The objective of this research is to develop a component based enhanced production process after End of Line (EOL) testing. This process will add more quality validation evaluations, but will not require any disassembling of the parts or damage to them. It will help the suppliers to avoid scrap and rework parts as well as General Motors (GM) to reduce warranty and recalls. An Enhanced Production Process was implemented in March, 2016 at a supplier in Mexico. The Enhanced Audit Station implementation is to ensure that the supplier is satisfying the Production Part Approval Process (PPAP) requirements. The most important four components are: Touch Appearance Lighting and Color (TALC), Appearance Approval Report (AAR), Dimensional Checks, and Function Testing. Through statistics, a pilot study was conducted to correlate the selected variables to reduce warranty.

In this experimental work, a flow field test system embedded with different vortex generators was installed to investigate the impact of vortex generation on heat transfer of air flow in a horizontal channel, and the flow structure was evaluated using a particle image velocimetry (PIV) system. Three different configurations of vortex generators were fitted vertically on a flat plate, at attack angles of 15o, 30o, and 45o, and tested at four different incoming air velocities. An axial fan was used to supply the flow of air through the test section. The effects of Reynolds number, attack angle, and the shape of vortex generators were examined in this work. The experimental results showed that, the presence of vortex generators had considerable effect on temperature distribution, pressure drop, and heat transfer augmentation in the channel flow.

In the present work, the effect of various nanofluids on automotive engine cooling was experimentally studied. Al2O3, TiC, SiC, MWNT (multi-walled nanotube), and SiO2 nanoparticles with average diameter ranging between 1 and 100 nm were mixed with distilled water to form nanofluids. An ultrasonic generator was used to generate uniform particle dispersion in the fluid. A compatibility test was carried out on all nanofluids and it was found that TiC, MWNT, and Si3N4 nanoparticles settled and separated from the fluid within 3 hours after preparation. The engine cooling performance testing setup consisted of an Aprilia SXV 450 engine, the nanofluid cooling loop, a radiator, a fan, etc. Thermocouples and resistance temperature detectors (RTD’s) were attached to the inlet and outlet of the radiator hose to monitor the temperature changes taking place in the cooling system. A flowmeter was attached to the inlet hose of the radiator to monitor the coolant flow rate.

Thermal management systems (TMS) of armored ground vehicle designs are often incapable of sustained heat rejection during high tractive effort conditions and ambient conditions. During these conditions, which mainly consist of high torque low speed operations, gear oil temperatures can rise over the allowable 275°F limit in less than twenty minutes. This work outlines an approach to temporarily store excess heat generated by the differential during high tractive effort situations through the use of a passive Phase Change Material (PCM) retrofit thereby extending the operating time, reducing temperature transients, and limiting overheating. A numerical heat transfer model has been developed based on a conceptual vehicle differential TMS. The model predicts the differential fluid temperature response with and without a PCM retrofit. The developed model captures the physics of the phase change processes to predict the transient heat absorption and rejection processes.

Bearings are a major component in any rotating system. With continually increasing speeds, bearing failure modes take new unconventional forms that often are not understood. In high speed applications, rolling element forces and gyroscopic moments can be significantly high compared to the applied forces acting on a bearing. Such moments create a “driving” torque causing outer race to creep. In this paper a mathematical model for the dynamics of a rolling element in a high speed bearing is derived. Preload values counterbalancing the torque driving the outer race to rotate can be predicted from this model. An attempt to experimentally measure this torque using a specially designed apparatus with integrated strain gauge torque sensor is also described. Both model and experimental measurements are aimed at understanding, and therefore preventing bearing failures due to outer race (creep) rotations.

The American Axle & Manufacturing Inc. driveline dynamometer provides immense value for experimental validation of product NVH performances. It has been intensively used to evaluate product design robustness in terms of build variations, mileage accumulation, and temperature sensitivity. The current driveline dynamometer input motor system has multiple torsional modes which create strong coupling with test part gear mesh dynamics. Mechanical Engineering seniors at Lawrence Technological University designed, fabricated, and validated a mechanism to decouple the driveline dynamics from the driveline dynamometer dynamics. The student-designed decoupler mechanism is presented with experimental validation of effectiveness in decoupling driveline dynamometer dynamics from the driveline under test.

An accurate prediction of elasto-plastic cyclic deformation becomes extremely important in design optimization. It also leads to more accurate fatigue life prediction and hence weight savings. In paper presents a two-stage notch root prediction method. This is based on a correction expression to Neuber's rule notch strain amplitude as the first stage, and a linear interpolation scheme as the second stage. The accuracy of this method is assessed by comparing the predicted results with the results obtained from elasto-plastic finite element analysis. Various types of steels with different yield strengths were used in this study. Notch deformation behavior under cyclic variable amplitude loading conditions was monitored for a double notched flat plate and a circumference notched round bar to cover plain stress and plain strain conditions. Elastic as well as elasto-plastic finite element analyses are performed.

A new inter-disciplinary degree program has been developed at Lawrence Technological University: the Master of Science in Mechatronic Systems Engineering Degree (MS/MSE). It is one of a few MS-programs in mechatronics in the U.S.A. today. This inter-disciplinary program reflects the main areas of ground vehicle mechatronic systems and robotics. This paper presents areas of scientific and technological principles which the Mechanical Engineering, Electrical and Computer Engineering, and Math and Computer Science Departments bring to Mechatronic Systems Engineering and the new degree program. New foundations that make the basis for the program are discussed. One of the biggest challenges was developing foundations for mechanical engineering in mechatronic systems design and teaching them to engineers who have different professional backgrounds. The authors first developed new approaches and principles to designing mechanical subsystems as components of mechatronic systems.

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.

The reliability of engine valve springs is a very important issue from the point of view of warranty. This paper presents a combined experimental and statistical analysis for predicting the fatigue limit of high tensile engine valve spring material in the presence of non-metallic inclusions. Experimentally, Fatigue tests will be performed on valve springs of high strength material at different stress amplitudes. A model developed by Murakami and Endo, which is based on the fracture mechanics approach, Extreme value statistics (GUMBEL Distribution) and Weibull Distribution will be utilized for predicting the fatigue limit and the maximum inclusion size from field failures. The two approaches, experimental and theoretical, will assist in developing the S-N curve for high tensile valve spring material in the presence of non-metallic inclusions.

This paper analyzes the difference in impact response of the forehead of the Hybrid III and THOR-NT dummies in free motion headform tests when a dummy strikes the interior trim of a vehicle. Hybrid III dummy head is currently used in FMVSS201 tests. THOR-NT dummy head has been in development to replace Hybrid III head. The impact response of the forehead of both the Hybrid III dummy and THOR dummy was designed to the same human surrogate data. Therefore, when the forehead of either dummy is impacted with the same initial conditions, the acceleration response and consequently the head Injury criterion (HIC) should be similar. A number of manufacturing variables can affect the impacted interior trim panels. This work evaluates the effect of process variation on the response in the form of Head Injury Criterion (HIC).

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.

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.

This paper is an introduction to the design of suspension components for a Formula SAE car. Formula SAE is a student competition where college students conceive, design, fabricate, and compete with a small formula-style open wheel racing car. The suspension components covered in this paper include control arms, uprights, spindles, hubs, pullrods, and rockers. Key parameters in the design of these suspension components are safety, durability and weight. The 2001 Lawrence Technological University Formula SAE car will be used as an example throughout this paper.

Aerodynamic drag is the force that restricts the forward velocity of a vehicle. Sources of drag are form drag, interference drag, internal flow drag, surface friction, and induced drag. Aerodynamic drag directly impacts the fuel economy attainable by a vehicle. In the Formula SAE competition (FSAE), fuel economy is a factor during the endurance phase. This paper will focus on the effects of aerodynamic drag and how it impacts the fuel economy of a FSAE racing style vehicle. Using the Lawrence Technological University (LTU) 1999 and 2000 cars to study and evaluate various methods to reduce drag and optimize fuel economy. Theoretical and experimental methods will be used and the study will be limited to the effects of form and interference drag.