Refine Your Search

Topic

Author

Affiliation

Search Results

Technical Paper

Optimum Engine Power Point Determination Method to Maximize Fuel Economy in Hybrid Vehicles

2021-04-06
2021-01-0419
One of the advantages of hybrid vehicles is the ability to operate the engine more optimally at a low brake specific fuel consumption (BSFC) as compared to conventional vehicles. This ability of hybrid vehicles is a major factor contributing to the fuel economy improvement over conventional vehicles. Unlike conventional gasoline powertrains, hybrid powertrains allow engine to be switched off and use battery power to propel vehicles. In order to maintain battery state of charge neutral operation between the start and end of a drive cycle, the net electrical energy consumption from the battery requires to be zero. An optimization algorithm can be developed and calibrated in different ways to achieve net zero battery energy over the cycle. For instance, the engine can be operated at powers higher than the power of the drive cycle to charge the battery. This accumulated energy can be used for all-electric propulsion by turning off the engine.
Technical Paper

Research on Vehicle Lane Change Based on Vehicle Speed Planning

2021-04-06
2021-01-0162
Lane changing manoeuvers is an essential rudiment in vehicle driving and has a significant impact on the characteristics of traffic flow. In the case of traditional cars, the driver operates the vehicle to complete the lane change whilst for autonomous vehicles, completing the lane change requires planning the lane change trajectory and controlling the vehicle speed during the lane change. Unreasonable lane change trajectory and vehicle speed may cause the vehicle to lose stability, threaten driving safety, increase energy consumption and waste energy. This paper considers the safety and economy of the lane changing process, and proposes a new lane changing method for vehicles.
Technical Paper

Dynamic Speed Limit for Self-Identifying Platoons of Mixed Vehicular Traffic on Freeways under Connected Environment

2021-04-06
2021-01-0168
Freeways and highway roads comprise about 200,000 of 4-million-mile public road network where a total of 5.3 trillion miles are traveled each year. Due to high contribution to mobility and energy consumption, freeways and highway have been attracting researchers to move more vehicles faster and in an energy-efficient manner. This includes developing better control methods able to sense real-time traffic, environmental factors, and road network characteristics. Traditional controls are vehicle actuated where the sensors are primarily fixed and have limited detecting capabilities. With the advent of connected vehicles (CVs), fixed sensor technology is being augmented with vehicle-based sensing. Moreover, pedestrians through their smart devices and non-motorized vehicles such as scooters, bikes are also being connected to get a better insight into the state of traffic.
Technical Paper

Assessing the Access to Jobs by Shared Autonomous Vehicles in Marysville, Ohio: Modeling, Simulating and Validating

2021-04-06
2021-01-0163
Autonomous vehicles are expected to change our lives with significant applications like on-demand, shared autonomous taxi operations. Considering that most vehicles in a fleet are parked and hence idle resources when they are not used, shared on-demand services can utilize them much more efficiently. While ride hailing of autonomous vehicles is still very costly due to the initial investment, a shared autonomous vehicle fleet can lower its long term cost such that it becomes economically feasible. This requires the Shared Autonomous Vehicles (SAV) in the fleet to be in operation as much as possible. Motivated by these applications, this paper presents a simulation environment to model and simulate shared autonomous vehicles in a geo-fenced urban setting.
Technical Paper

Assessing the Impacts of Dedicated CAV lanes in a Connected Environment: An application of Intelligent Transport Systems in Corktown, Michigan

2021-04-06
2021-01-0177
The interaction of Connect and Automated vehicles (CAV) with regular vehicles in the traffic stream has been extensively researched. Most studies, however, focus on the calibrating driver behavior models for CAVs based on various levels of automation and driver aggressiveness. Other related studies largely focus on the coordination of CAVs and infrastructure like traffic signals to optimize traffic. However, the effects of different strategic orchestrations of CAVs in the traffic stream in the comparative scenario-based analysis is understudied. Thus, this study develops a framework and simulations for integrating CAVs in a corridor section. We develop a calibrated model with CAVs for a corridor section in Corktown, Michigan, and simulate how dedicated CAV lane operations can be implemented without significant change in existing infrastructure.
Technical Paper

A Hybrid method for Automotive Entity Recognition

2021-04-06
2021-01-0179
Over the past decades, automotive industry has made substantial investments in automation solutions, electric and autonomous vehicles and advanced product technologies for enhancing vehicular communication and so on. The rise of industry 4.0 brings out a revolutionary transformation in the automotive industry with low-cost computing, high-speed connectivity, and machine learning that have enabled the digitization of the physical world, transforming insights into optimized actions. These technologies have an important role in the growth and future of automotive domain. Hence it is relevant and important to get insight of different OEMs (Original Equipment Manufacturer) at different geographical locations and their focusing technologies adapted currently and in the nearby future. In this paper, we are implementing a hybrid method for entity recognition, which is a combination of both rule-based and machine learning based entity recognition techniques.
Technical Paper

Analyzing the impact of Electric Vehicles Charging Stations on Power Quality in Power Distribution System

2021-04-06
2021-01-0199
Electric vehicles (EVs) have become one of the promising solutions to decrease the impact of fossil fuel combustion engines on the environment. In spite of their significant role in decreasing air pollutants, EVs could have adversarial impacts on quality of power in electric grids. Electric vehicles use rechargeable batteries to store the energy and run their electric engines. EVs’ battery chargers use power electronic switches to convert AC voltage to DC voltage, leading to power quality issues due to its non-linearity. Non-linear loads have negative impacts on power quality and can cause several problems such as voltage unbalance, voltage fluctuations, low power factors, and harmonics in power distribution systems. Charging a high number of electric vehicles will create power quality issues and cause harmonic distortions. Harmonics affect the performance of power transformers by increasing power losses and reducing their output power.
Technical Paper

A Real-time Curb Detection Method for Vehicle by Using a 3D-LIDAR Sensor

2021-04-06
2021-01-0076
Effectively detecting road boundaries in real time is critical to the applications of autonomous vehicles, such as vehicle localization, path planning and environmental understanding.To precisely extract the road boundaries from the 3D LiDAR data, a real-time curb detection algorithm consisting of four steps is proposed in this paper.
Technical Paper

Accurate Pressure Control based on Driver Braking Intention Identification for a Novel Integrated Braking System

2021-04-06
2021-01-0100
With the development of intelligent and electric vehicles, higher requirements are put forward for the active braking and regenerative braking ability of the braking system. The traditional braking system equipped with vacuum booster has difficulty meeting the demand, therefore it has gradually been replaced by the Integrated Braking System. In this paper, a novel integrated braking system is presented, which mainly contains a pedal feel simulator, a permanent magnet synchronous motor(PMSM), a series of transmission mechanisms, and the hydraulic control unit. As an integrative system of mechanics-electronics-hydraulics, the Integrated Braking System has complex nonlinear characteristics, which challenge accurate pressure control. Furthermore, it is a completely decoupled braking system, the pedal force doesn’t participate in pressure-building, so it is necessary to precisely identify driver’s braking intention.
Technical Paper

High-Definition Map based Motion Planning, and Control for Urban Autonomous Driving

2021-04-06
2021-01-0098
This paper presents motion planning and control algorithm for urban automated driving using high-definition(HD) map. Many automakers have developed and commercialized advanced driver assistance system(ADAS) based on vision-only lane extraction in motorway environments. Compared to the motorway environments where the lane is continuous and clearly visible, however, in urban roads, degradation of the lane quality such as lane occlusion and lane loss occurs frequently. This leads to the poor quality of the local guide path for the autonomous vehicles with vision-only lane extraction. Global HD map is used to provide the lane information continuously instead of vision-only lane extraction. With the existence of global position of host vehicle and the HD map, the proposed sequential algorithm performs the lane keeping and lane changing decision and control with safety margin in multi-vehicle situation.
Technical Paper

Arrangement and Control Method of Cooperative Vehicle Platoons

2021-04-06
2021-01-0113
With the development of cellular communication technology and for the sake of reducing drag resistance, the multi-lane platoons technology will be more prosperous in the future. In this article, the cooperative vehicle platoons method on the public road is represented. The method’s architecture is composed of the following parts: behavior decision, path planning and vehicle dynamic control. The behavior decision uses the finite state machine to make decision and judgment on the cooperative lane change of vehicles, and starts to execute the lane change step when the lane change conditions are met. In terms of path planning, with the goal of ensuring comfort, the continuity of the vehicle state and no collision between vehicles, a fifth-order polynomial is used to fit every vehicle trajectory. In terms of vehicle dynamic control, a model predictive control algorithm is used to solve the multi-vehicle centralized optimization control problem.
Technical Paper

Unstructured with a Point: Validation and Robustness Evaluation of Point-Cloud Based Path Planning

2021-04-06
2021-01-0251
Robust autonomous navigation in unstructured environments is an unsolved problem and critical to the operation of autonomous military and rescue ground vehicles. Two-dimensional path planners operating on occupancy grids or costs maps can produce infeasible paths when the operational area includes complex terrain. Recently, sample-based path planners that plan on LiDAR-acquired point-cloud maps have been proposed. These approaches require no discretization of the operational area and provide direct pose estimation by modeling vehicle and terrain interaction. In this paper, we show that direct sample-based path planning on point clouds is effective and robust in unstructured environments. Robustness is demonstrated by completing a system parameter sensitivity analysis of the system in an Unreal simulation environment and partnered with field validation.
Technical Paper

A Study on Heat Dissipation of Electric Vehicle Motor based on Heat-pipe Heat Transfer Analysis

2021-04-06
2021-01-0208
With the increasingly serious problems of environmental pollution and energy shortage, electric vehicles have a promising future. As a core component of electric vehicles, the drive motor is developing towards high power density of which remains temperature rise problems, which affects the performance, efficiency and service life of the drive motor. Liquid cooling has high energy consumption and poor reliability. The heat-pipe has excellent heat conduction and temperature uniformity capabilities. Therefore, this paper proposes a heat pipe-based drive motor heat dissipation system to make the heat-pipe act on the inside of the motor to reach a specified range of driving conditions. The drive motor can better dissipate heat through the heat-pipe. Firstly, analysis of the internal heat generation mechanism of the motor, heat transfer characteristics of the heat-pipe and the heat-pipe layout plan was established.
Technical Paper

Impact of Thermal Architecture on Electric Vehicle Range: A Study with Full Vehicle Simulation

2021-04-06
2021-01-0207
Electric vehicles suffer from dramatic energy loss in cold and hot climate, resulting in range reduction up to 50% at -20ºC ambient and 20% at 40ºC ambient. Energy consumption by thermal management systems are responsible for most of the range loss. Energy-efficient designs for thermal management systems are therefore crucial for retaining nominal vehicle range, while ensuring proper thermal conditions for battery, drive unit, cabin climate systems, electric/compute systems, etc. To investigate the impact of thermal architectural choices on energy consumption at vehicle level, full vehicle level simulations were carried out with an in-house simulation platform, which was built as a system-engineering tool to study the interaction among hierarchies of vehicle systems, subsystems and components.
Technical Paper

A Practical Approach towards Reducing the HVAC Flow Noise

2021-04-06
2021-01-0216
Automotive heating ventilating and air conditioning (HVAC) noise is becoming a big concern area as the demand for acoustic comfort increases day by day. Vehicle manufactured in recent years with quieter powertrain, reduced body leakage, better suspension and other quieter technology like electrification, hybridization etc. further toughens the situation. Hence designing a HVAC with very low sound pressure level is quite challenging and poses many difficulties in meeting other basic performances due to certain trade-off while meeting the noise requirement. However in recent years engineers have done extensive research and come up with various affordable and non-affordable solutions in order to reduce the HVAC noise significantly. Most commonly used tool and technique is numerical simulation and experimental investigation or combined numerical followed by experimental. The present paper describes the way an existing HVAC noise was reduced by extensive experimental investigations.
Technical Paper

Decision-Making for Autonomous Mobility Using Remotely Sensed Terrain Parameters in Off-Road Environments

2021-04-06
2021-01-0233
Off-road vehicle operation requires constant decision-making under great uncertainty. Such decisions are multi-faceted and range from acquisition decisions to operational decisions. A major input to these decisions is terrain information in the form of soil properties. This information needs to be propagated to path planning algorithms that augment them with other inputs such as visual terrain assessment and other sensors. In this sequence of steps many resources are needed and it is not often clear how best to utilize them. We present an integrated approach where a mission’s overall performance is measured using a multiattribute utility function. This framework allows us to evaluate the value of acquiring terrain information and then its use in path planning. The computational effort of optimizing the vehicle path is also considered and optimized. We present our approach on the data acquired from the Keweenaw Research Center terrains and present some results. DISTRIBUTION A.
Technical Paper

Supervised terrain classification with adaptive unsupervised terrain assessment

2021-04-06
2021-01-0250
Off road navigation demands ground robots to traverse complex and often changing terrain. Classification and assessment of terrain can improve path planning strategies by reducing travel time and energy. In this paper we introduce a terrain classification and assessment framework that relies on both exteroceptive and proprioceptive sensor modalities. The robot captures an image of the terrain it is about to traverse and records corresponding vibration data during traversal. These images are manually labelled and used to train a support vector machine (SVM) in an offline training phase. Images have been captured under different lighting conditions and across multiple locations to achieve diversity and robustness to the model. Acceleration data is used to calculate statistical features that capture the roughness of the terrain whereas angular velocities are used to calculate roll and pitch angles experienced by the robot.
Technical Paper

Nondestructive Radar-Based Terrain Evaluation Towards Autonomous Off-Road Vehicle Control

2021-04-06
2021-01-0254
Military ground vehicles operate in off-road environments traversing different terrains under various environmental conditions. There has been an increasing interest towards autonomous off-road vehicle navigation, leading to the development of perception-based terrain traversability assessment methods. These methods utilized data-driven approaches on classical robotic perception sensing modalities (RGB cameras, Lidar, and depth cameras) positioned in front of ground vehicles in order to observe approaching terrain. Classical robotic sensing modalities, though effective for describing environment geometry and object detection and tracking, aren’t able to directly observe features related to compaction and moisture content which have significant effects on the moduli properties governing terrain mechanics. These methods then become very specialized to specific regions and environmental conditions which are inevitably subject to change.
Technical Paper

On the Expansion of On-Board Diagnostics (OBD) to Electric Propulsion Systems

2021-04-06
2021-01-0439
Currently the On-Board Diagnostics (OBD) requirements enforced by government agencies do not cover electric vehicles. For example, California Air Resources Board (CARB) mandates all light duty and medium duty vehicles equipped with fuel-powered engines, including all hybrid vehicles, to follow the OBD requirements in California Code of Regulation (CCR) 1968.2. Electric vehicles (EVs), instead, are completely exempted from any OBD requirements. Due to the strong needs from the customers on obtaining the standard vehicle service information, from the manufactures to commonize the diagnostic strategies across different platforms, and from the legislators to monitor system health and prevent catastrophic failures, the OBD requirement enforcement on EVs are right around the corner. This paper, different from other published technical papers or proposals from different OEMs or government agencies, is based on the existing HEV requirements in U.S.
Technical Paper

Structural Design and Simulation Analysis of an Intelligent Speed Bump

2021-04-06
2021-01-0324
As a traffic deceleration device, speed bumps are widely used to reduce the speed of vehicles and have good effect. However, in special occasions such as hospital entrance, the joltss caused by ordinary speed bumps are likely to aggravate the pain of patients. In view of this situation, an intelligent speed bump is designed in this paper, which can adjust the surface of the speed bump according to the speed of passing vehicles. When a low-speed vehicle passes by, the elastic link slider mechanism works, and the upper surface of the speed bump can be elastically lowered to improve the ride comfort of low-speed vehicles. When a high-speed vehicle passes by, the centrifugal locking mechanism will lock the elastic link slider mechanism, and the upper surface of the speed bump will be locked, which plays a role in speed limit. In this paper, SolidWorks and ADAMS / car co-simulation are used to analyze the process of vehicle passing through the intelligent speed bump.
X