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RFID Selection, Application, and Use in Aerospace, Space, and Transportation

Radio Frequency Identification (RFID) is an enabling technology that has been widely adopted in the retail industry. The powers of RFID are acknowledged by many, but a lack of understanding of the technology, its limitations, and how to select the right plan for its target installation has slowed efforts to migrate the technology into the aerospace, space, and transportation industries. While RFID is not a new technology, the rate at which it has been integrated into the aerospace industry has been slow due to unique considerations regarding qualification, regulations, and safety.
Journal Article

General Modeling of Nonlinear Isolators for Vehicle Ride Studies

2010-04-12
2010-01-0950
The advancements made in modeling and parameter identification of nonlinear isolation components in the underlying investigation confirm the importance of accurate Multibody Dynamics modeling of these components for reducing vibration and/or improving ride comfort. Considering dynamic stiffness and loss angle characteristics, the proposed nonlinear isolation component uses the Bouc/Wen hysteresis model for excitation amplitude dependency and a transfer function for excitation frequency dependency. Various combinations of Bouc/Wen hysteresis parameters result in different shapes for hysteresis loops and allows for modeling a wide range of soft and stiff isolator characteristics. The effect of the proposed isolation component on ride studies is illustrated by simulating a maneuver on a road profile using the OpenCRG road description with SimXpert Motion Workspace and Adams/Car. Tire belt dynamics are captured by adding a rigid ring part to the PAC2002 tire model [ 1 ].
Journal Article

The Influence of Vibration on Friction

2009-10-11
2009-01-3015
This paper summarizes results from the author's work on friction in dry sliding contacts in the presence of vibration. A number of idealized models of smooth and rough contacts are examined. It is shown that vibration can cause up to a 10% reduction in average friction even with continuous contact. A larger reduction in friction occurs when there is intermittent contact loss. This is found to be true for both elastic and plastic contacts, and for adhesive and plowing mechanisms of friction. The results of this work are compared and validated with measurements from experiments. The results presented are fundamental, but applicable to machine components with contacts including brake systems.
Technical Paper

Development of a Dual-Clutch Transmission System for ATVs

2009-04-20
2009-01-0514
A demand for the easy driving made possible by automatic transmissions has been rising recently, even in the category of All-Terrain Vehicles (ATVs), which are mostly used off road. At the same time, from a practical usage point of view, users are still conscious of both fuel economy and drivability. Thus, the authors focused on developing a dual-clutch transmission system, which would combine the ease of use of an automatic transmission and the efficiency of a conventional manual transmission. Conventional dual-clutch transmission systems that have been developed for passenger vehicles are difficult and complicated to fit onto ATVs as they are. In particular, the shifting system complicates the total mechanism, by appending a number of parts as the control device. We therefore developed a new shifting system that consists of manual transmission components like dog-clutch type gears, a shift-drum system, and a shifting motor.
Technical Paper

Vortex Ring-like Structures in a Non-evaporating Gasoline-fuel Spray: Simplified Models versus Experimental Results

2010-05-05
2010-01-1491
The results of recent developments of analytical vortex ring models and the applications of these models to interpretation of the experimentally observed dynamics of vortex ring-like structures in gasoline sprays, under non-evaporating conditions, are summarized. Analytical formulae in the limit of small Reynolds numbers (Re), are compared with numerical solutions. Particular attention is focused on the generalized vortex ring model in which the time evolution of the thickness of the vortex ring core L is approximated as atb, where a and b are constants (1 ≤ b ≤ 1/2). This model incorporates both the laminar model for b=1/2 and fully turbulent model for b=1/4. The values of velocities in the region of maximal vorticity, predicted by the generalized vortex ring model, are compared with the results of experimental studies of fuel droplets distributed in vortex ring-like structures in two gasoline injectors, under cold-start, engine-like conditions.
Technical Paper

Experimental Investigation of Cavitation in Gasoline Injectors

2010-05-05
2010-01-1500
Spray characteristics of injectors depend on, among other factors, not only the level of turbulence upstream of the nozzle plate, but also on whether cavitation arises. "Bulk" cavitation, by which we mean cavitation which arises far from walls and thus far from streamline curvature associated with salient points on a wall, has not been investigated thoroughly experimentally and moreover it is quite challenging to predict by means of computational fluid dynamics. Information about the effect of the injector geometry on the formation of bulk cavitation and quantitative measurements of the flow field that promotes this phenomenon in gasoline injectors does not exist and this forms the background to this work. Evolution of bulk cavitation was visualized in two gasoline multi-hole injectors by means of a fast camera.
Technical Paper

Auto-Tuning of PID Controllers for Calibration of Idle Speed Controller Maps in Diesel Engines

2010-04-12
2010-01-0330
In this work we propose an automatic tuning method for the calibration of PID controllers of the idle speed functionality in Diesel engines. The tuning method is based on a closed-loop identification technique, which is employed to estimate the parameters of a first order model with integrator and delay. It is shown that this simple model has sufficient fidelity to provide satisfactory PID gains. The identification algorithm and the performance of the resulting PID controllers have been tested in different vehicles. The proposed methodology has the potential to automate the calibration process of idle speed controllers while satisfying requirements on stability, performance, and robustness of the closed-loop system.
Technical Paper

Simplifying the Review of Communicating Finite State Machines Implementation using Static Analysis

2016-04-05
2016-01-0035
Abstract Finite State Machines (FSMs) are used at various stages of software development, from the initial concept of software system to the lowest level implementation. These FSMs communicate non-deterministically with the other FSMs and the environment of the underlying system. Any inappropriate handling of the communication across multiple FSMs or environment may lead to unexpected behavior of the underlying system. Manual detection of the root cause of such unexpected behavior is effort intensive. Moreover, state of art techniques focus mainly on design level review of communicating FSMs (Comm-FSMs), and no technique is available for systematic review of Comm-FSMs at implementation level. In this paper we present a review technique for detecting inconsistencies in the implementation of Comm-FSMs.
Technical Paper

The Effect of Hill Planning and Route Type Identification Prediction Signal Quality on Hybrid Vehicle Fuel Economy

2016-04-05
2016-01-1240
Abstract Previous research has demonstrated an increase in Fuel Economy (FE) using an optimal controller based on limited foreknowledge using methods such as Engine Equivalent Minimization Strategy (ECMS) and Stochastic Dynamic Programming (SDP) with stochastic error in the prediction signal considerations. This study seeks to quantify the sensitivity of prediction-derived vehicle FE improvements to prediction signal quality assuming optimal control. In this research, a hill pattern and route type identification scenario control subjected to varying prediction signal quality is selected for in depth study. This paper describes the development of a baseline Toyota Prius Hybrid Vehicle (HV) simulation models, real world drive cycles and real-world disturbances, and an optimal controller incorporating a prediction of vehicle power requirements.
Technical Paper

Driving Style Identification Algorithm with Real-World Data Based on Statistical Approach

2016-04-05
2016-01-1422
Abstract This paper introduces a new method for driving style identification based on vehicle communication signals. The purpose of this method is to classify a trip, driven in a vehicle, into three driving style categories: calm, normal or aggressive. The trip is classified based on the vehicle class, the type of road it was driven on (urban, rural or motorway) and different types of driving events (launch, accelerating and braking). A representative set of parameters, selected to take into consideration every part of the driver-vehicle interaction, is associated to each of these events. Due to the usage of communication signals, influence factors, other than vehicle speed and acceleration (e.g. steering angle or pedals position), can be considered to determine the level of aggressiveness on the trip. The conversion of the parameters from physical values to dimensionless score is based on conversion maps that consider the road and vehicle types.
Journal Article

Identification of Vortical Structure that Drastically Worsens Aerodynamic Drag on a 2-Box Vehicle using Large-scale Simulations

2016-04-05
2016-01-1585
Abstract It is important to reduce aerodynamic drag for reducing fuel consumption. Conventionally reduction of aerodynamic drag has been carried out by shape optimization of each part of a vehicle based on the investigations of the time-averaged flows around the vehicle. However, the general tendency of drag reduction has been saturated recently and it is required to develop a new flow-control technique to achieve further reduction in aerodynamic drag. We therefore focus on the unsteadiness of the flow around a vehicle to achieve it because the aerodynamic drag of a vehicle fluctuates over time due to repetitions of generation, growth, merging and disappearance of various sizes of vortices around it. These vortices are formed by flow separations, for which the longitudinal coherent vortices inside turbulent boundary layers on vehicle surfaces are presumably playing an important role.
Journal Article

Vehicle Longitudinal Control Algorithm Based on Iterative Learning Control

2016-04-05
2016-01-1653
Abstract Vehicle Longitudinal Control (VLC) algorithm is the basis function of automotive Cruise Control system. The main task of VLC is to achieve a longitudinal acceleration tracking controller, performance requirements of which include fast response and high tracking accuracy. At present, many control methods are used to implement vehicle longitudinal control. However, the existing methods are need to be improved because these methods need a high accurate vehicle dynamic model or a number of experiments to calibrate the parameters of controller, which are time consuming and costly. To overcome the difficulties of controller parameters calibration and accurate vehicle dynamic modeling, a vehicle longitudinal control algorithm based on iterative learning control (ILC) is proposed in this paper. The algorithm works based on the information of input and output of the system, so the method does not require a vehicle dynamics model.
Journal Article

Identification of True Stress-Strain Curve of Thermoplastic Polymers under Biaxial Tension

2016-04-05
2016-01-0514
Abstract This article is concerned with identification of true stress-strain curve under biaxial tension of thermoplastic polymers. A new type of biaxial tension attachment was embedded first in a universal material test machine, which is able to transform unidirectional loading of the test machine to biaxial loading on the specimen with constant velocity. Cruciform specimen geometry was optimized via FE modeling. Three methods of calculating true stress in biaxial tension tests were compared, based on incompressibility assumption, linear elastic theory and inverse engineering method, respectively. The inverse engineering method is more appropriate for thermoplastic polymers since it considers the practical volume change of the material during biaxial tension deformation. The strategy of data processing was established to obtain biaxial tension true stress-strain curves of different thermoplastic polymers.
Journal Article

Both-Sides Welding Technology for Resin Fuel Tubes

2016-04-05
2016-01-0506
Abstract This study developed technology for simultaneously welding heterogeneous resin tubes in order to weld and integrate resin tubes with two different specifications (low temperature and high temperature). The aim of integration was cost and weight reduction. The cost reduction due to reducing the number of parts exceeded the increase in material cost due to a change to resin materials. Base material fracture of the resin tubes was set as the breaking format condition, and the welding parameters of the joint part rotations and the friction time between the joint part and the resin tubes were specified as the weld strength judgment standard. In addition, the fused thickness determined by observing the cross-section after welding was specified as the weld quality judgment standard. The range over which weld boundary peeling does not occur and weld strength is manifest was clarified by controlling the welding parameters and the fused thickness.
Technical Paper

Modeling and Measurement of Payload Mass of the Wheel Loader in the Dynamic State based on Experimental Parameter Identification

2016-04-05
2016-01-0469
Abstract This paper presents payload estimation based on experimental friction coefficients identification. To estimate exact payload mass, dynamic mathematical model such as actuator dynamics and front linkage dynamics is derived by using Newton-Euler method. From the dynamic equation, nonlinear terms are analyzed and transformed. And a friction model is derived from the experiments with various conditions which have three states; boom joint angle, head and rod chamber pressures. It can identify friction coefficients and compensate friction forces. In addition, the accuracy of payload estimation system is verified through the field test.
Technical Paper

Placement Technique of Measurement Points for Inverse Acoustic Analysis

2015-11-17
2015-32-0747
This paper describes a measurement points' placement technique for the sound source identification using inverse acoustic analysis. In order to reduce noise in NVH problem for various kinds of machines including small size engine, it is necessary to identify the sound source. The inverse acoustic analysis is a technique that is effective for the sound source identification.[1,2] The inverse acoustic analysis identifies a surface vibration of an object by measuring the radiated sound and solving the inverse problem. Nakano et al. researched about the location of sound pressure measurement points for accurate improvement.[3] They clarified that the sound pressure measurement points on the concentric circle gave more accurate surface vibration than the measurement points on the square lattice.
Technical Paper

Accident Analysis of a Two-Lane National Highway in India

2015-01-14
2015-26-0162
Abstract Road accidents and persons killed in India have been reported to the tune of 4,90,383 and 1,38,258 respectively during 2012. On National Highways (NHs), major share of accidents (about 29%) and number of persons killed (35.3%) are observed out of total accidents. National Highways in India constitute about 2% of total road network (92,851 km) in India, but carries about 40% of traffic. 46% (42,829 km) of NHs in India comprises of two-lane and about 19% (17239 km) of NHs are single or intermediate-lane. Road accidents being multi-disciplinary in nature involves attention of multiple departments such as Highways Authority, Police, Motor Vehicles, Automobile Manufacturers, NGOs, etc. Owing to spurt in growth of motor vehicle population in India, road accidents are not reduced significantly despite improvement in NHs (widening of carriageway and riding quality).
Technical Paper

Load Identification of a Suspension Assembly Using True-Load Self Transducer Generation

2016-04-05
2016-01-0429
Abstract The performance of a structural design significantly depends upon the assumptions made on input load. In order to estimate the input load, during the design and development stage of the suspension assembly of a BAJA car, designers and analysts invest immense amount of time and effort to formulate the mathematical model of the design. These theoretical formulations may include idealization errors which can affect the performance of the car as a final product. Due to the errors associated with the assumption of design load, several components might have more weight or may have less strength than needed. This discrepancy between the assumed input load (lab or theoretical studies) and the actual load from the environment can be eliminated by performing a real life testing process using load recovery methodology. Commercial load cells exist in industry to give engineers insight to understanding the complex real world loading of their structures.
Journal Article

Development of a Parameter Identification Method for MF-Tyre/MF-Swift Applied to Parking and Low Speed Manoeuvres

2016-04-05
2016-01-1645
Abstract A vehicle parking manoeuvre is characterized by low or zero speed, small turning radius and large yaw velocity of the steered wheels. To predict the forces and moments generated by a wheel under these conditions, the Pacejka Magic Formula model has been extended to incorporate the effect of spin (turn slip model) in the past years. The extensions have been further developed and incorporated in the MFTyre/MF-Swift 6.2 model. This paper describes the development of a method for the identification of the turn slip parameters. Based on the operating conditions of a typical parking manoeuvre, the dominant parameters of the turn slip model are firstly defined. At an indoor test facility, the response of a tyre under the identified operating conditions is measured. An algorithm is developed to identify the dominant turn slip parameters from the measured responses.
Journal Article

Source Separations and Identification by Structural Holography

2016-06-15
2016-01-1799
Abstract The source field reconstruction aims at identifying the excitation field measuring the response of the system. In Near-field Acoustic Holography, the response of the system (the radiated acoustic pressure) is measured on a hologram using a microphones array and the source field (the acoustic velocity field) is reconstructed with a back-propagation technique performed in the wave number domain. The objective of the present works is to use such a technique to reconstruct displacement field on the whole surface of a plate by measuring vibrations on a one-dimensional holograms. This task is much more difficult in the vibratory domain because of the complexity of the equation of motion of the structure. The method presented here and called "Structural Holography" is particularly interesting when a direct measurement of the velocity field is not possible.
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