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In order to further improve the vehicle economy of hybrid vehicles, this paper first discusses the existing hybrid energy management strategies, and analyzes the shortcomings of the existing strategies considering the actual road conditions, and points out the importance of future road condition information to energy management. Then, an energy prediction management strategy by acquiring future road condition information is proposed. The main work of this paper is centered on this strategy. This strategy is to use information about future working conditions provided by navigation and other sensing systems and predict energy consumption in future working conditions, so as to optimize the energy management strategy between engine and motor. The strategy is mainly composed of four parts: future information acquisition, future energy consumption prediction, energy management target calculation, and control target execution.

Aiming at the trajectory planning of autonomous vehicles in lane changing under muti-lane traffic scenarios, a multi-lane lane change decision and trajectory planning algorithm based on Logic Regression Algorithm and Gaussian Probability Model is proposed. Firstly, the target state (time and velocity) of vehicle during lane change is sampled and lateral trajectory (5th polynomial) and longitudinal trajectory (4th polynomial) are planned based on the target state; Secondly, cost evaluation function of trajectory is established and optimal trajectory is selected based on three aspects of safety, comfort and lane changing time.

This paper presents a theoretical study of a finite hybrid piezoelectric phononic crystal (PC) beam with shunting circuits. The vibration transmissibility method (TM) is developed for the finite system. The uniform and non-uniform configurations of the resonators, piezoelectric patches and shunting circuits are respectively considered. The properties of the vibration attenuation of the hybrid PC beam undergoing bending vibration are investigated and quantified. It is shown that the proper relaxation of the periodicity of the PC is conducive to forming a broad vibration attenuation region. The hybrid piezoelectric PC combines the purely mechanical PC with the piezoelectric PC and provides more tunable mechanisms for the target band-gap. Taking the structural and circuit parameters into account, the design of experiments (DOE) method and the multi-objective genetic optimization method are employed to improve the vibration attenuation and meet the lightweight demand of the attachments.

While over 30% of US occupant fatalities occur in rollover crashes, no dummy has been developed for such a condition. Currently, an efficient, cost-effective methodology is being implemented to develop a biofidelic rollover dummy. Instead of designing a rollover dummy from scratch, this methodology identifies a baseline dummy and modifies it to improve its response in a rollover crash. Using computational models of the baseline dummy, including both multibody (MB) and finite element (FE) models, the dummy’s structure is continually modified until its response is aligned (using BioRank/CORA metric) with biofidelity targets. A previous study (Part I) identified the THOR dummy as a suitable baseline dummy by comparing the kinematic responses of six existing dummies with PMHS response corridors through laboratory rollover testing.

Recreational Off-Highway Vehicles (ROVs), since their introduction onto the market in the late-1990s, have been related to over 300 fatalities with the majority occurring in vehicle rollover. In recent years several organizations made attempts to improve ROV safety. This paper is intended to evaluate ejection mitigation measures considered by the ROV manufacturers. Evaluated countermeasures include two types of occupant restraints (three and four point) and two structural barriers (torso bar, door with net). The Rollover protection structure (ROPS) provided by the manufacturer was attached to a Dynamic Rollover Test System (DRoTS), and a full factorial series of roll/drop/catch tests was performed. The ROV buck was equipped with two Hybrid III dummies, a 5th percentile female and a 95th percentile male. Additionally, occupant and vehicle kinematics were recorded using optoelectronic stereophotogrammetric camera system.

Multiple laboratory dynamic test methods have been developed to evaluate vehicle crashworthiness in rollover crashes. However, dynamic test methods remove some of the characteristics of actual crashes in order to control testing variables. These simplifications to the test make it difficult to compare laboratory tests to crashes. One dynamic method for evaluating vehicle rollover crashworthiness is the Dynamic Rollover Test System (DRoTS), which simulates translational motion with a moving road surface and constrains the vehicle roll axis to a fixed plane within the laboratory. In this study, five DRoTS vehicle tests were performed and compared to a pair of unconstrained steering-induced rollover tests. The kinematic state of the unconstrained vehicles at the initiation of vehicle-to-ground contact was determined using instrumentation and touchdown parameters were matched in the DRoTS tests.

Rollover crashes are a serious public health problem in United States, with one third of traffic fatalities occurring in crashes where rollover occurred. While it has been shown that occupant kinematics affect the injury risk in rollover crashes, no anthropomorphic test device (ATD) has yet demonstrated kinematic biofidelity in rollover crashes. Therefore, the primary goal of this study was to assess the kinematic response biofidelity of six ATDs (Hybrid III, Hybrid III Pedestrian, Hybrid III with Pedestrian Pelvis, WorldSID, Polar II and THOR) by comparing them to post mortem human surrogate (PMHS) kinematic response targets published concurrently; and the secondary goal was to evaluate and compare the kinematic response differences among these ATDs.

The objective of the current study was to characterize the whole-body kinematic response of restrained PMHS in controlled laboratory rollover tests. A dynamic rollover test system (DRoTS) and a parametric vehicle buck were used to conduct 36 rollover tests on four adult male PMHS with varied test conditions to study occupant kinematics during the rollover event. The DRoTS was used to drop/catch and rotate the test buck, which replicated the occupant compartment of a typical mid-sized SUV, around its center of gravity without roof-to-ground contact. The studied test conditions included a quasi-static inversion (4 tests), an inverted drop and catch that produced a 3 g vertical deceleration (4 tests), a pure dynamic roll at 360 degrees/second (11 tests), and a roll with a superimposed drop and catch produced vertical deceleration (17 tests). Each PMHS was restrained with a three-point belt and was tested in both leading-side and trailing-side front-row seating positions.

Three dimensional, steady state computational fluid dynamics (CFD) simulations of flow around a generic pickup truck are performed to optimize the aerodynamic performance of a pickup truck model. Detailed comparison between the data of the CFD model and the experiment are made. By using deformation techniques, surrogate models and optimization methods, the drag is reduced. Four design variables are used for deformation: the cabin height, bed height, ground clearance and bed length. The optimization is single objective: minimizing the drag coefficient. A response surface model is built to reduce the sampling points for optimization, and the simulation time is reduced accordingly. Results show that the design variables are not fully independent with each other, and by proper combinations of the variable change, the drag coefficient of the pickup truck model can be reduced effectively. In this study, the drag coefficient reduced about 9.7% through optimization algorithm.

Traditional testing approaches for fundamental battery materials focus on highly artificial test profiles, for example constant current (CC) or constant voltage (CV) testing. Additionally, the currents used for capacity and cycle tests are often very low. These profiles are not indicative of the types of current/voltage profiles that the battery will experience during actual vehicle operation. As a result, these simple tests may fail to sufficiently elicit the reduction in performance and failure modes that occur during more dynamic cycling. In this paper, we outline an approach in which vehicle-level modeling is applied to regulatory drive cycles in order to derive power vs. time requirements for an energy storage system. These requirements are used to identify segments of the regulatory drive cycles that present significant challenges to the battery. Finally, the most stressing portions of the drive cycle are used to determine limiting physical characteristics of batteries.

This paper deals with a new kind of driving module of solenoid valves which can be used in electronic diesel injection systems such as unit pumps, unit injectors and common rail injectors. A typical structure of solenoid driving circuitry and the so called Peak&Hold current waveform is introduced first. Then analysis of driving voltage on solenoid responding characteristics, which are the key factors for precise electronic controlling of injector valves, is carried out and summarized based on finite element model of solenoid valves. After that, the schematic drawing of a new kind of driving module is presented. The structure and parameter selection process of the two main parts of this module, the DC/DC converter and PWM(Pulse With Modulating) signal generator, are depicted in detail.

The arcing faults on cables of aerospace power systems represent a major safety concern for spacecraft. To ensure the normal operation of the Power Management and Distribution (PMAD) system, it is necessary that remedial control strategies are developed and implemented. Most of the research in this area deal mainly with arcing faults in terrestrial distribution power systems that operate as AC systems rather than DC systems. The paper investigates the application of a new digital signal processing technique – Fast Fourier Transform (FFT) based energy spectrum estimation – to analyze the recorded signals of DC arcing faults. The data is collected from the DC arcing experiment at the NASA Glenn research center. The voltage level range is from 50Vdc to 150Vdc. This paper presents a feature extraction approach to transform the signal representation from time-domain into frequency-domain. Results demonstrate the distinctive difference between the pre-fault signal and post-fault signal.

In spacecraft energy power system (EPS), the objective of fault protection is to detect and respond to spacecraft faults. Its purpose is to eliminate single point failures or their effects and to ensure the spacecraft system integrity under anomalous conditions. Also, it is important to keep the continuity of the power supply and at the same time increase the reliability of spacecraft Energy power system. One of most deadly faults is arcing faults, which are accompanied by very erratic waveform variations. The sustainable current level in the arc is not sufficient to be reliably detected by conventional means. Feeder current signal analysis provides a solution to this detection problem. A Fast Fourier Transform method is applied to decompose the monitored voltage and current signals into a series of detailed spectral components. The spectral energies are calculated and then employed to train a neural network to identify arcing faults accurately.