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A critical limitation preventing newer FSAE teams from improving in the international rankings is that of the person-machine interface, where driver inexperience and lack of training lead to loss of traction. The Traction Control System (TCS) described here uses closed-loop control of available engine power via spark retardation. Two distinct, driver-selectable algorithms were developed which govern TCS operation for either 1) launch control for the straight line acceleration event, or 2) full traction control for all other dynamic events. Launch control uses a spark retard rev limit to allow the driver to hold the engine at the ideal RPM for easy rev matching via flat foot shifting. Wheel speeds are simultaneously monitored to achieve ideal tire slip ratios. The full traction control algorithm uses the launch control method as a basis, but also addresses potential need for corner exit oversteer or engine braking.

Manifold tuning has long been considered a critical facet of engine design and performance optimization. This paper details the design, analysis and preliminary testing of a continuously variable, carbon fiber intake manifold for a restricted 2003 Suzuki GSXR-600® engine. The device achieves a large dynamic runner length range of 216-325 mm through the use of a half-tube, sliding shell design that differs substantially from traditional variable intake approaches. A combination of Ricardo WAVE® and 2D/3D Ansys Fluent® simulations were used to aid in the design of the intake along with a custom software routine to optimize restrictor geometry through fully automated CFD simulations. The sliding mechanism was actuated via a cable linkage system and powered by a small servo motor. This motor was controlled by a Microchip dsPIC® microcontroller that was embedded in a custom power distribution PCB for the 2009 Cooper Union Formula SAE® entry.

This work details the process employed to design the 2009 Cooper Union FSAE® suspension system, spanning the overarching design philosophy, configuration selection, analysis, fabrication, and implementation, while offering recommendations to those especially new to the field. The design methodology illustrated here provides a systematic approach to suspension geometry, material selection, packaging, and construction. Though this paper serves as a starting point for FSAE® suspension designers, it provides a succinct overview for those interested in general suspension design fundamentals. The design process began with the selection of a suspension configuration, geometries, and kinematics, which were driven in part by tire data, desired bulk vehicle dynamics characteristics, and overall geometric variability. The springs and adjustable dampers were then selected as the front and rear anti-roll bar properties were concurrently designed.

The engine tuning study presented here serves as an introduction to the basic concepts of implementing a motorcycle engine on an eddy current dynamometer test stand. This work represents the first engine tuning effort of a young FSAE® team and depicts the common challenges encountered by novice teams. The torque and power characteristics of a restricted 600 cc Suzuki GSXR engine were tuned in order to deliver the performance demands of an FSAE® vehicle. Coarse baseline fuel and ignition maps were initially developed manually and then optimized via a closed-loop algorithm. User-defined air-fuel ratios were automatically maintained throughout the engine's operating regime during this optimization process. Performance data were logged throughout each tuning cycle where spark timing and air-fuel ratio were varied accordingly to maximize power output. Spark settings were located approximately 10% before the knock threshold identified using a knock sensor.

Manifold tuning has long been a critical facet of engine design and performance optimization. This paper details the design, analysis, and initial fabrication of a variable runner length intake manifold for a restricted 2003 Suzuki GSXR 600 engine. A series of analytical Helmholtz resonance calculations were first performed to assess the feasibility of such a system. A comprehensive CFD study was then performed using a combination of Ricardo WAVE® and Fluent® simulations. Custom software was developed to optimize restrictor geometry through fully automated CFD simulations whose results were investigated to determine the optimal transition for the intended flow characteristics. This resulting candidate geometry was then used with a variable intake design in a Ricardo WAVE® manifold dynamics model and was varied iteratively to yield an optimum final geometry.

A low-cost, high precision strain gauge data acquisition system was designed and implemented to aid in optimizing the design of suspension and steering members in an FSAE vehicle. The primary focus of the project was to capture load limits in A-arms, steering tie-rods, and toe control linkages and to extract the dynamic response of the suspension system when subjected to steady-state cornering and bump scenarios. These data are critical considerations needed to systematically and aggressively address suspension material selection and fabrication, vehicle dynamic response, and weight savings. In addition, the data from this system were intended to enhance the accuracy of imposed FEA boundary conditions, corroborate on-road system responses to simulated data, and provide a cost-effective, wireless alternative for a wide range of low-level electrical signals throughout the vehicle.

The increasing push to accelerate the product design process and to minimize physical testing expense has promoted the development of hardware-in-the-loop testing procedures which couple well-defined virtual models with physical systems. Clear advantages include: 1) the advanced screening of candidate designs and control algorithms earlier in the product development phase, 2) lower overall testing cost to the manufacturer, 3) faster test times for design iterations, and 4) greater flexibility in the types of tests possible. This paper describes the design of an economical system that uses a parameterized, model-based vehicle simulation to control the operation of powertrain test cell hardware as part of a real-time test procedure. A commercially available vehicle simulation package allows for the modeling of a variety of chassis and powertrain combinations, along with a wide range of test procedures.

Medium trucks constitute a large market segment of the commercial transportation sector, and are also used widely for military tactical operations. Recent technological advances in hybrid powertrains and fuel cell auxiliary power units have enabled design alternatives that can improve fuel economy and reduce emissions dramatically. However, deterministic design optimization of these configurations may yield designs that are optimal with respect to performance but raise concerns regarding the reliability of achieving that performance over lifetime. In this article we identify and quantify uncertainties due to modeling approximations or incomplete information. We then model their propagation using Monte Carlo simulation and perform sensitivity analysis to isolate statistically significant uncertainties. Finally, we formulate and solve a series of reliability-based optimization problems and quantify tradeoffs between optimality and reliability.

The need for a rigorous systems engineering approach to automotive powertrains has been addressed in this work from the perspective of the diesel engine. A high-fidelity engine simulation has been integrated with a total vehicle model for the purpose of reverse engineering the optimal powerplant for a given vehicle mission. Engine parameters have been coordinated between the simulations to develop a framework for total vehicle design. The design strategies discussed in this paper allow engine researchers to set targets for individual system components and to analyze the tradeoffs associated with different vehicle mission objectives. A detailed case study employing these techniques is presented for a conventional vehicle where the most fuel-efficient engine is found that simultaneously conforms to the desired performance criteria.

A regenerative braking model for a parallel Hybrid Electric Vehicle (HEV) is developed in this work. This model computes the line and pad pressures for the front and rear brakes, the amount of generator use depending on the state of deceleration (i.e. the brake pedal position), and includes a wheel lock-up avoidance algorithm. The regenerative braking model has been developed in the symbolic programming environment of MATLAB/SIMULINK/STATEFLOW for downloadability to an actual HEV's control system. The regenerative braking model has been incorporated in NREL's HEV system simulation called ADVISOR. Code modules that have been changed to implement the new regenerative model are described. Resulting outputs are compared to the baseline regenerative braking model in the parent code. The behavior of the HEV system (battery state of charge, overall fuel economy, and emissions characteristics) with the baseline and the proposed regenerative braking strategy are first compared.