Browse Topic: Roads and highways

Items (1,009)
ABSTRACT Consumer demand and regulatory pressure have forced automakers to develop features designed to increase passenger car safety regardless of road surface or weather condition. In response, the intelligent tire, proposed in the APOLLO report, is introduced and the parameters useful for traction control system development are identified. Traction control system models are introduced and discussed. A simple vehicle model based on the quarter-car is presented, incorporating a traction control system and tire friction model. This model utilizes the LuGre friction model to relate tractive force to slip ratio and road surface friction level. A sliding-mode control strategy is chosen to model traction control behavior. Three case studies are conducted on two simulated road surfaces to show the interaction between estimated friction level in the sliding-mode control strategy and the tire friction model. To simulate the intelligent tire, where the road surface friction level is directly
Binns, RobertTaheri, SaiedFerris, John B.
This study proposes a multi-mode switching control strategy based on electromagnetic damper suspension (EMDS) to address the different performance requirements of suspension systems on variable road surfaces. The working modes of EMDS are divided into semi-active damping mode and energy harvest mode, and the proposed mode switching threshold is the weighted root mean square value of acceleration. For the semi-active damping mode, a controller based on LQR(Linear Quadratic Regulator) was designed, and a variable resistance circuit was also designed to meet the requirements of the semi-active mode, which optimized the damping effect relative to passive suspension. For the energy harvest mode, an energy harvest circuit was designed to recover vibration energy. In order to reduce the deterioration of suspension performance caused by frequent mode switching in the mode switching strategy, as frequent system switching can lead to system disorder, deterioration of damping effect, and
Zeng, ShengZhang, BangjiTan, BohuanQin, AnLai, JiewenWang, Shichen
The highway diverging area is a crucial zone for highway traffic management. This study proposes an evaluation method for traffic flow operations in the diverging area within an Intelligent and Connected Environment (ICE), where the application of Connected and Automated Vehicles (CAVs) provides essential technical support. The diverging area is first divided into three road sections, and a discrete state transition model is constructed based on the discrete dynamic traffic flow model of these sections to represent traffic flow operations in the diverging area under ICE conditions. Next, an evaluation method for the self-organization degree of traffic flow is developed using the Extended Entropy Chaos Degree (EECD) and the discrete state transition model. Utilizing this evaluation method and the Deep Q-Network (DQN) algorithm, a short-term vehicle behavior optimization method is proposed, which, when applied continuously, leads to a vehicle trajectory optimization method for the
Fang, ZhaodongQian, PinzhengSu, KaichunQian, YuLeng, XiqiaoZhang, Jian
ABSTRACT Tracks and wheels are some of the top constituents of ground vehicle mobility and sustainment cost. Even small improvements in performance parameters and support strategies can go a long way. Analyzing equipment sustainment models can help identify these opportunities in conjunction with maintaining a situational awareness of R&D activities. Specifically, understanding component failure analysis, characterizing production road wheel material properties, conducting component testing, and benchmarking diverse manufacturing capabilities provides a roadmap to establishing and identifying “Best in Class” road wheel materials. Establishing and executing an R&D compounding plan to deliver 5X-10X durability improvement is hypothesized. Leveraging the Defense Mobility Enterprise (DME) and its authority under the 10 USC 2370 Section 845 Ground Vehicle Systems Other Transaction Agreement will allow the government to rapidly determine the technical feasibility of realizing such colossal
Patria, Garett S.Rescoe, StuBradford, WilliamMynderse, James A.
ABSTRACT This paper presents the comparative analysis of virtual and experimental proving ground for the performance capabilities of front suspensions in the Family of Medium Tactical Vehicles (FMTV) cargo truck. The front suspension of the current baseline FMTV is a solid axle with leaf springs and shock absorbers. Two other types of suspensions including passive and semi-active suspensions are evaluated in solid and fully independent axle configurations. Virtual proving ground for on- and off-road tests are simulated in the Trucksim environment to include constant radius circular steer, double lane change, sinusoidal steer, washboard road surfaces, and half-round curb strike. Physical proving ground tests are conducted to provide some experimental correlation and validation of the baseline vehicle simulation results. The comprehensive experiments also evaluate the capabilities of various suspensions which have been considered in future FMTV design for mobility performance improvement
Liao, Y. GeneCard, BrandonWasylyk, John
ABSTRACT Commercial OEMs are fast realizing the long awaited dream of self-driving trucks and cars. The technology continues to improve with major implications for the Army. In the near tear, the impact may be most profound for military installations. Many believe, however, that the major limiting factor to wide-spread automated vehicle usage will not be technology but the human element. What happens when humans through no choice of their own are compelled to interact with self-driving vehicles? We propose a mixed-methods research study that examines the complex transportation system from both a technical and social perspective. This study will inform environmental controls (rules of the road and infrastructure modifications) and increase understanding of the social dynamics involved with vehicle acceptance. Findings may pave the way for a reduction in the over $400M the Army spends annually on non-tactical vehicles and the technical improvements, grounded in dual-use use cases will be
Straub, Edward
In recent years, autonomous vehicles (AVs) have been receiving increasing attention from investors, automakers, and academia due to the envisioned potentials of AVs in enhancing safety, reducing emissions, and improving comfort. The crucial task in AV development boils down to perception and navigation. The research is underway, in both academia and industry, to improve AV’s perception and navigation and reduce the underlying computation and costs. This article proposes a model predictive control (MPC)-based local path-planning method in the Cartesian framework to overcome the long computation time and lack of smoothness of the Frenet method. A new equation is proposed in the MPC cost function to improve the safety in path planning. In this regard, an AV is built based on a 2015 Nissan Leaf S by modifying the drive-by-wire function and installing environment perception sensors and computation units. The custom-made AV then collected data in Norman, Oklahoma, and assisted in the
Arjmandzadeh, ZibaAbbasi, Mohammad HosseinWang, HanchenZhang, JiangfengXu , Bin
From televisions to smartphones, organic light-emitting diodes (OLEDs) are finding their way into many everyday devices. For use in displays, blue OLEDs are also required to supplement the primary colors — red and green. Especially in blue OLEDs, impurities give rise to strong electrical losses, which could be partly circumvented by using highly complex and expensive device layouts
While semi-active suspensions help improve the ride comfort and road-holding capacity of the vehicle, they tend to be reactive and thus leave a lot of room for improvement. Incorporating road preview data allows these suspensions to become more proactive rather than reactive and helps achieve a higher level of performance. A lot of preview-based control algorithms in literature tend to require high computational effort to arrive at the optimal parameters thus making it difficult to implement in real time. Other algorithms tend to be based upon lookup tables, which classify the road input into different categories and hence lose their effectiveness when mixed types of road profiles are encountered that are difficult to classify. Thus, a novel MPC (model predictive control)-based algorithm is developed which is easy to implement online and more responsive to the varying road profiles that are encountered by the vehicle. The efficacy of the algorithm is tested against a numerical methods
Thamarai Kannan, Harish KumarFerris, John B.
The construction of urban transportation infrastructures on the supply side is severely limited due to the extensive development of central urban land. Therefore, optimizing the traffic structure with limited resources is particularly important. The work used the optimum capacity of the road network as one of the constraints. Multi-objective linear programming was used to establish the traffic structure model. The total travel volume, energy consumption, travel quality, and social cost were selected as the optimization objectives of the urban transportation structure. The influencing factors of infrastructure capacity (e.g., total travel demand, optimal capacity of road network, slow traffic capacity, and parking lot capacity) were selected as the constraint conditions in optimizing urban transportation structure. The objective was to develop an optimization model considering the constraints of urban infrastructure. Finally, the optimal traffic structure was compared with the actual
Zhang, JinweiGao, Jianping
Dynamic wireless charging (DWC) systems can make up electrified roads (eRoads) on which electricity from the grid is supplied to electric vehicles (EVs) wirelessly while the EVs travel along the roads. Electrification of roads contributes to decarbonizing the transport sector and offers a strong solution to high battery cost, range anxiety, and long charging times of EVs. However, the DWC eRoads infrastructure is costly. This article presents a model to minimize the infrastructure cost so that the deployment of eRoads can be economically more feasible. The investment for eRoad infrastructure consists of the costs of various components including inverters, road-embedded power transmitter devices, controllers, and grid connections. These costs depend on the traffic flow of EVs. The configuration and deployment strategy of the proposed eRoads in Southeastern Canada are designed with optimized charging power and DWC coverage ratio to attain the best cost-effectiveness. Well-designed
Qiu, KuanrongRibberink, HajoEntchev, Evgueniy
Coyner, KelleyBittner, JasonLambermont, SergeDe Boer, Niels
Understanding left-turn vehicle-pedestrian accident mechanisms is critical for developing accident-prevention systems. This study aims to clarify the features of driver behavior focusing on drivers’ gaze, vehicle speed, and time to collision (TTC) during left turns at intersections on left-hand traffic roads. Herein, experiments with a sedan and light-duty truck (< 7.5 tons GVW) are conducted under four conditions: no pedestrian dummy (No-P), near-side pedestrian dummy (Near-P), far-side pedestrian dummy (Far-P) and near-and-far side pedestrian dummies (NF-P). For NF-P, sedans have a significantly shorter gaze time for left-side mirrors compared with light-duty trucks. The light-duty truck’s average speed at the initial line to the intersection (L1) and pedestrian crossing line (L0) is significantly lower than the sedan’s under No-P, Near-P, and NF-P conditions, without any significant difference between any two conditions. The TTC for sedans is significantly shorter than that for
Matsui, YasuhiroNarita, MasashiOikawa, Shoko
Taking the semi-active suspension system as the research object, the forward model and inverse model of a continuous damping control (CDC) damper are established based on the characteristic test of the CDC damper. A multi-mode semi-active suspension controller is designed to meet the diverse requirements of vehicle performance under different road conditions. The controller parameters of each mode are determined using a genetic algorithm. In order to achieve automatic switching of the controller modes under different road conditions, a method is proposed to identify the road roughness based on the sprung mass acceleration. The average of the ratio between the squared sprung mass acceleration and the vehicle speed within a specific time window is taken as the identification indicator for road roughness. Simulation results show that the proposed road roughness identification method can accurately identify smooth roads (Class A–B), slightly rough roads (Class C), and severely rough roads
Feng, JieyinYin, ZhihongXia, ZhaoWang, WeiweiShangguan, Wen-BinRakheja, Subhash
Compared with urban areas, the road surface in mountainous areas generally has a larger slope, larger curvature and narrower width, and the vehicle may roll over and other dangers on such a road. In the case of limited driver information, if the two cars on the mountain road approach fast, it is very likely to occur road blockage or even collision. Multi-vehicle cooperative control technology can integrate the driving data of nearby vehicles, expand the perception range of vehicles, assist driving through multi-objective optimization algorithm, and improve the driving safety and traffic system reliability. Most existing studies on cooperative control of multiple vehicles is mainly focused on urban areas with stable environment, while ignoring complex conditions in mountainous areas and the influence of driver status. In this study, a digital twin based multi-vehicle cooperative warning system was proposed to improve the safety of multiple vehicles on mountain roads. First, implement
Tian, LihengYu, ZiruiChen, Xinguo
Under complex and extreme operating conditions, the road adhesion coefficient emerges as a critical state parameter for tire force analysis and vehicle dynamics control. In contrast to model-based estimation methods, intelligent tire technology enables the real-time feedback of tire-road interaction information to the vehicle control system. This paper proposes an approach that integrates intelligent tire systems with machine learning to acquire precise road adhesion coefficients for vehicles. Firstly, taking into account the driving conditions, sensor selection is conducted to develop an intelligent tire hardware acquisition system based on MEMS (Micro-Electro-Mechanical Systems) three-axis acceleration sensors, utilizing a simplified hardware structure and wireless transmission mode. Secondly, through the collection of real vehicle experiment data on different road surfaces, a dataset is gathered for machine learning training. This dataset is subsequently analyzed to discern the tire
Han, ZongzhiLiu, WeidongLiu, DayuGao, ZhenhaiZhao, Yang
This Electric Road System was devised that would provide electric power to EVs directly from the infrastructure so that EVs could undergo intermittent charging while driving. This system is a conductive dynamic charging system that operates from the side of the vehicle (roadside), and research has been underway on the application of this approach to passenger cars and race cars. This paper focused on resolving issues with freight vehicles, which account for most of the CO2 emissions in the transportation sector. This Electric Road System that operates by contact from the roadside was applied to heavy-duty trucks, which have been considered a challenge to convert to EVs, and at the same time the infrastructure technology was also expanded and evolved. And verification tests using actual vehicles were conducted for regenerative energy absorption control of a charging vehicle while driving. The results confirmed that this control system appropriately controls the distribution of power
Tajima, TakamitsuAbe, Hiroyuki
With economic development and the increasing number of vehicles in cities, urban transport systems have become an important issue in urban development. Efficient traffic signal control is a key part of achieving intelligent transport. Reinforcement learning methods show great potential in solving complex traffic signal control problems with multidimensional states and actions. Most of the existing work has applied reinforcement learning algorithms to intelligently control traffic signals. In this paper, we investigate the agent-based reinforcement learning approach for the intelligent control of ramp entrances and exits of urban arterial roads, and propose the Proximal Policy Optimization (PPO) algorithm for traffic signal control. We compare the method controlled by the improved PPO algorithm with the no-control method. The simulation experiments used the open-source simulator SUMO, and the results showed that the reinforcement learning control ramp technique increases the average
Ouyang, ChenZhan, ZhenfeiQian, LiuzhuZou, Jie
In 2021, 412,432 road accidents were reported in India, resulting in 153,972 deaths and 384,448 injuries. India has the highest number of road fatalities, accounting for 11% of the global road fatalities. Therefore, it is important to explore the underlying causes of accidents on Indian roads. The objective of this study is to identify the factors inherent in accidents in India using clustering analysis based on self-organizing maps (SOM). It also attempts to recommend some countermeasures based on the identified factors. The study used Indian accident data collected by members of ICAT-ADAC (International Centre for Automotive Technology - Accident Data Analysis Centre) under the ICAT-RNTBCI joint project approved by the Ministry of Heavy Industries, Government of India. 210 cases were collected from the National Highway between Jaipur and Gurgaon and 239 cases from urban and semi-urban roads around Chennai were used for the analysis. Based on this study, the following results were
Vimalathithan, KulothunganRao K M, PraneshVallabhaneni, PratapnaiduSelvarathinam, VivekrajManoharan, JeyabharathPal, ChinmoyPadhy, SitikanthaJoshi, Madhusudan
Driver's driving style has a great impact on lane changing behavior, especially in scenarios such as freeway on-ramps that contain a strong willingness to change lanes, both in terms of inter-vehicle interactions during lane changing and in terms of the driving styles of the two vehicles. This paper proposes a study on game-theoretic decision-making for lane-changing on highway on-ramps considering driving styles, aiming to facilitate safer and more efficient merging while adequately accounting for driving styles. Firstly, the six features proposed by the EXID dataset of lane-changing vehicles were subjected to Principal Component Analysis (PCA) and the three principal components after dimensionality reduction were extracted, and then clustered according to the principal components by the K-means algorithm. The parameters of lane-changing game payoffs are computed based on the clustering centers under several styles. Secondly, a neural network model is designed based on the Matlab
Du, HangXu, NanZhang, Zeyang
With the rapid advancement in intelligent vehicle technologies, comprehensive environmental perception has become crucial for achieving higher levels of autonomous driving. Among various perception tasks, monitoring road types and evenness is particularly significant. Different road categories imply varied surface adhesion coefficients, and the evenness of the road reflects distinct physical properties of the road surface. This paper introduces a two-stage road perception framework. Initially, the framework undergoes pre-training on a large annotated drivable area dataset, acquiring a set of pre-trained parameters with robust generalization capabilities, thereby endowing the model with the ability to locate road areas in complex regions. Subsequently, guided by a mask attention mechanism, the model undergoes fine-tuning on a smaller dataset annotated with road type regions using a weighted joint loss function, effectively addressing issues of class imbalance and limited labeled samples
Wei, KaiYu, Liangyaoxu, Feng
Whenever bicyclists ride on public roads, they ride through roadway defects which occasionally causes them to lose control of their bicycles and/or damage components. Previous research has quantified the forces experienced during general road and offroad riding, but did not study the specific influences of variables such as pothole geometry, riding speed, etc. To begin quantifying these effects, a road bike was equipped with a triaxial accelerometer and ridden over poor roadway conditions around an industrial park in Southern California. Next, in a laboratory setting, an artificial pothole was constructed that was 12 inches long and either 1 or 1.65 inches deep. A force plate was placed at the far edge to measure the horizontal loads induced by the bicycle tire riding over the edge and high-speed camera was positioned perpendicular to the path of travel to measure the speed and vertical drop of the front wheel. Lastly, two riders of differing weights rode the same road bicycle over the
Sweet, David MichaelBretting, GeraldWilhelm, Christopher
As a key tool to maintain urban cleanliness and improve the road environment, road cleaning vehicles play an important role in improving the quality of life of residents. However, the traditional road cleaning vehicle requires the driver to monitor the situation of road garbage at all times and manually operate the cleaning process, resulting in an increase in the driver 's work intensity. To solve this problem, this paper proposes a road garbage recognition algorithm based on improved YOLOv5, which aims to reduce labor consumption and improve the efficiency of road cleaning. Firstly, the lightweight network MobileNet-V3 is used to replace the backbone feature extraction network of the YOLOv5 model. The number of parameters and computational complexity of the model are greatly reduced by replacing the standard convolution with the deep separable convolution, which enabled the model to have faster reasoning speed while maintaining higher accuracy. Secondly, the attention mechanism in
Liu, XinHongWen, ZihaoKang, KaileiLiu, Xingchen
Road roughness is the most important source of vertical loads for road vehicles. To capture this during durability engineering, various mathematical models for describing road profiles have been developed. The Laplace process has turned out to be a suitable model, which can describe road profiles in a more flexible way than e.g., Gaussian processes. The Laplace model essentially contains two parameters called C and ν (to be explained below), which need to be adapted to represent a road with certain roughness properties. Usually, local road authorities provide such properties along a road on sections of constant length, say, 100 m. Often the ISO 8608 roughness coefficient or the IRI (International Roughness Index) are used. In such cases, there are well known explicit formulas for finding the parameters C and ν of the Laplace process, which best fits the road under certain assumptions. Besides local road authorities there are also other sources of roughness data, for instance commercial
Speckert, MichaelDahlheimer, ThorstenFiedler, Jochen
Recognizing road conditions using onboard sensors is significant for the performance of intelligent vehicles, and the road profile is a widely accepted representation both in the temporal and frequency domains, greatly influencing driving quality. In this paper, a recurrent neural network embedded with attention mechanisms is proposed to reconstruct the road profile sequence. Firstly, the road and vehicle sensor signals are obtained in a simulated environment by modeling the road, tire, and vehicle dynamic system. After that, the models under different working conditions are trained and tested using the collected data, and the attention weights of the trained model are then visualized to optimize the input channels. Finally, field experiments on the real vehicle are conducted to collect real road profile data, combined with vehicle system simulation, to verify the performance of the proposed method
Shi, RunwuYang, ShichunLu, JiayiChen, YuyiWang, RuiCao, RuiLi, Zhuoyang
Ergonomics plays an important role in automobile design to achieve optimal compatibility between occupants and vehicle components. The overall goal is to ensure that the vehicle design accommodates the target customer group, who come in varied sizes, preferences and tastes. Headroom is one such metric that not only influences accommodation rate but also conveys a visual perception on how spacious the vehicle is. An adequate headroom is necessary for a good seating comfort and a relaxed driving experience. Headroom is intensely discussed in magazine tests and one of the key deciding factors in purchasing a car. SAE J1100 defines a set of measurements and standard procedures for motor vehicle dimensions. H61, W27, W35, H35 and W38 are some of the standard dimensions that relate to headroom and head clearances. While developing the vehicle architecture in the early design phase, it is customary to specify targets for various ergonomic attributes and arrive at the above-mentioned
Rajakumaran, SriramS, RahulVasireddy, Rakesh MitraNair, Suhas
In 2018, the state explicitly proposed to “promote the cancellation of expressway toll stations at provincial boundaries.” Electronic toll collection (ETC) has become the main toll collection method on expressways. With the construction of ETC toll lanes, the proportion of ETC vehicles in the expressway traffic flow is increasing, and the rapid processing of vehicle special situations is facing challenges. At present, various provinces have adopted various methods to improve the traffic efficiency and transaction success rate of ETC from the issuance link, customer service link, and lane transaction link. According to statistical data, the average transaction success rate of ETC lane is not higher than 99% at present. As of October 2021, the number of ETC users nationwide has reached 256 million, and there are an average of 40 million ETC transactions per day across the network, that is, about 400,000 special cases need to be processed. How to efficiently deal with special vehicles in
Guo, XiaohuiGuo, FengbinZhang, MengweiZheng, FengfeiLiu, Chunya
An automatic collision avoidance control method integrating optimal four-wheel steering (4WS) and direct yaw-moment control (DYC) for autonomous vehicles on curved road is proposed in this study. Optimal four-wheel steering is used to track a predetermined trajectory, and DYC is adopted for vehicle stability. Two single lane change collision avoidance scenarios, i.e., a stationary obstacle in front and a moving obstacle at a lower speed in the same lane, are constructed to verify the proposed control method. The main contributions of this article include (1) a quintic polynomial lane change trajectory for collision avoidance on curved road is proposed and (2) four different kinds of control method for autonomous collision avoidance, namely 2WS, 2WS+DYC, 4WS, and 4WS+DYC, are compared. In the design of DYC controller, two different feedback control methods are adopted for comparison, i.e., sideslip angle feedback and yaw rate feedback. The simulation results demonstrate significant
Lai, Fei
The advent of autonomous vehicles promises to revolutionize the transportation sector globally, and India, as one of the world's fastest-growing economies, stands at the forefront of this transformative technology. This paper presents a brief overview of the current state and potential implications of autonomous vehicles in the Indian context. With its densely populated cities, diverse traffic conditions, and complex road infrastructure, India presents unique challenges and opportunities for the deployment of autonomous vehicles. This technology has the potential to address critical issues such as road safety, congestion, and pollution while transforming the mobility experience for millions of people. However, several hurdles must be overcome to fully harness its benefits. The paper explores key considerations for the implementation of autonomous vehicles in India. These include adapting the technology to navigate chaotic traffic scenarios, addressing infrastructure limitations, and
Shetty, Sharan Harish
The Construction & Mining field is continuously upgrading, reshaping under the stimulus of technical enhancement. India is considered one of fastest growing country in the word. Requirement for Construction Equipment Vehicles in India is continuously growing due increased rate infrastructure development. To promote development of the Construction Equipment Vehicles (CEV’s) manufacturing sector it was also necessary to build a new governance architecture. Every vehicle plying on road has to comply with Central Motor Vehicle Regulatory requirements as per CMVR act 1989. Earlier 2021 CEV’s were required to go through performance trials like brake, steering effort, turning circle measurement, speedometer calibration as dynamic tests as per regulations. It was need of the time to come with stringent norms or for better safety of operators & take CEV compatible international regulation. this paper puts forward the basic principles & safety requirements improved for CEV’s over the time
Babar, SagarAkbar Badusha, A
Accurately predicting the future trajectories of surrounding traffic agents is important for ensuring the safety of autonomous vehicles. To address the scenario of frequent interactions among traffic agents in the highway merging area, this paper proposes a trajectory prediction method based on interactive graph attention mechanism. Our approach integrates an interactive graph model to capture the complex interactions among traffic agents as well as the interactions between these agents and the contextual map of the highway merging area. By leveraging this interactive graph model, we establish an agent-agent interactive graph and an agent-map interactive graph. Moreover, we employ Graph Attention Network (GAT) to extract spatial interactions among trajectories, enhancing our predictions. To capture temporal dependencies within trajectories, we employ a Transformer-based multi-head self-attention mechanism. Additionally, GAT are utilized to model the interactions between traffic agents
Wu, XigangChu, DuanfengDeng, ZejianXin, GuipengLiu, HongxiangLu, Liping
With the progressing autonomy of driving technology, machine is assuming greater responsibility for driving tasks to enhance safety. Leveraging this potential, this paper introduces a novel human-machine co-steering control strategy based on model predictive control. The strategy is designed to address the difficulties faced by drivers when driving on surfaces with low adhesion. Firstly, the proposed strategy utilizes a parallel human-machine co-steering framework with a weight allocation concept between the controller and the driver. Moreover, the nonlinear controller dynamics model and linear driver dynamics model are developed to characterize the interaction behaviors between human and machine under low-adhesion road surface conditions. And a nonlinear game optimization problem is formulated to capture the cooperative interaction relationship between human and machine. Finally, to solve the nonlinear game optimization problem, piecewise affine linearization method is employed to
Guo, HongyanHu, ShiboShi, WanqingLiu, Jun
For intelligent vehicles, a fast and accurate estimation of road slope is of great significance for many aspects, including the steering comfort, fuel economy, vehicle stability control, driving decision-making, etc. But the commonly used estimation methods nowadays usually demand additional sensors or complex dynamic models, causing increase in system complexity as well as decrease in accuracy. To solve these problems, this paper puts forward a real-time road slope estimation algorithm leveraging the relationship between pitch angle and road slope, which only requires low sensors cost and computational complexity. Firstly, a GNSS/INS fusion system is established to obtain the pitch angle with respect to the navigation frame, which couples the vehicle’s pitch angle in vehicle frame and road slope angle. Then, based on the different characteristics in frequency domain of the two components, frequency domain analysis is conducted and low-pass filter is used to separate out road slope
Chen, MengyuanXiong, LuGao, Letian
The development of autonomous driving generally requires enormous annotated data as training input. The availability and quality of annotated data have been major restrictions in industry. Data synthesis techniques are then being developed to generate annotated data. This paper proposes a 2D data synthesis pipeline using original background images and target templates to synthesize labeled data for model training in autonomous driving. The main steps include: acquiring templates from template libraries or alternative approaches, augmenting the obtained templates with diverse techniques, determining the positioning of templates in images, fusing templates with background images to synthesize data, and finally employing the synthetic data for subsequent detection and segmentation tasks. Specially, this paper synthesizes traffic data such as traffic signs, traffic lights, and ground arrow markings in 2D scenes based on the pipeline. The effectiveness of this pipeline was verified on the
Bie, XiaofangZhang, SongMeng, ChaoMei, JinrenLi, JianHe, Xin
This study investigates the use of a road weather model (RWM) as a virtual sensing technique to assist autonomous vehicles (AVs) in driving safely, even in challenging winter weather conditions. In particular, we investigate how the AVs can remain within their operational design domain (ODD) for a greater duration and minimize unnecessary exits. As the road surface temperature (RST) is one of the most critical variables for driving safety in winter weather, we explore the use of the vehicle’s air temperature (AT) sensor as an indicator of RST. Data from both Road Weather Information System (RWIS) stations and vehicles measuring AT and road conditions were used. Results showed that using only the AT sensor as an indicator of RST could result in a high number of false warnings, but the accuracy improved significantly with the use of an RWM to model the RST. ROC-curve analysis resulted in an AUC value of 0.917 with the AT sensor and 0.985 with the RWM, while the true positive rate
Almkvist, EsbenDavid, Mariana AlvesPedersen, Jesper LandmérLewis-Lück, RebeccaHu, Yumei
Engine start timing of series hybrid system is important for quietness in the cabin and comfortable because its engine operation timing is not restricted by vehicle speed and acceleration. There is an opportunity to operate the engine without spoiling quietness if engine sounds could be covered by road noise. Discovering the correlation between road noise and variance of wheel angular acceleration using wheel speed sensor made it possible to estimate road noise. Engine start control based on this road noise estimation algorithm contributes to cabin quietness performance improvement as the result of less frequency of engine operating during smooth road driving
Sawada, TakanobuYamauchi, YasuhiroTeraji, AtsushiGotou,, MasayaAizumi, ShoMatsuoka, HisayoshiEnomoto, Toshio
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