Procedural Generation of Road Paths for Driving Simulation

2015 ◽  
Vol 6 (2) ◽  
pp. 37-55 ◽  
Author(s):  
Carlos Campos ◽  
João Miguel Leitão ◽  
António Fernando Coelho
Keyword(s):  
Traffic Engineering ◽  
Three Dimensional ◽  
Scientific Work ◽  
Driving Simulation ◽  
Driving Simulators ◽  
Design Standards ◽  
Road Engineering ◽  
The Road ◽  
Procedural Generation ◽  
Three Dimensional Models

Virtual environments for driving simulation aimed to scientific purposes require realistic three-dimensional models of roads. The creation of road models for these purposes, is usually preceded by the design of road paths which fulfill all the desired specific characteristics. Traditionally, the design of road paths is performed by road engineering specialists, resulting in a very time-consuming task. This paper presents a method that allows the procedural generation of road paths aimed to driving simulation experiments (e.g., ergonomics, psychology and traffic engineering). This method is inspired in methods used in roadways engineering, producing roads according to the design standards and similar to those found in the real world. This significantly reduces the need of specialists to prepare the road paths and generate road models suitable for conducting scientific work in driving simulators.

The Research of Public Traffic Safety Evaluation System

2012 ◽  
Vol 253-255 ◽  
pp. 1855-1859
Author(s):  
Pei Chen ◽  
Xuan Liu ◽  
Jian Gang Qiao
Keyword(s):  
Traffic Safety ◽  
Public Transport ◽  
Traffic Engineering ◽  
Evaluation System ◽  
Safety Evaluation ◽  
Analytic Hierarchy ◽  
Road Engineering ◽  
The Road ◽  
Public Traffic ◽  
Transport Safety

In order to improve the security of public traffic, In the road engineering, traffic engineering facilities for basic theory,analyze the factors that affect public transport safety,and then conduct extensive questionnaire,analyze the degree that the major transport facilities affect the safety of traffic,determine the evaluation index and use the analytic hierarchy construct public transport safety evaluation system.Finally,applicate evaluation system to determine the best time for preventive maintenance of road markings,and also provide a new way of thinking for the study of traffic safety.

scholarly journals Stability Analysis of Long Combination Vehicles Using Davies Method

2020 ◽  
Author(s):  
Gonzalo Guillermo Moreno Contreras ◽  
Rodrigo de Souza Vieira ◽  
Daniel Martins
Keyword(s):  
Load Capacity ◽  
Slope Angle ◽  
Three Dimensional ◽  
Vehicle Stability ◽  
Transport Costs ◽  
Gravity Center ◽  
The Road ◽  
Mechanism Model ◽  
Longitudinal Slope ◽  
Three Dimensional Models

The cargo transportation in the world is mostly dominated by road transport, using long combination vehicles (LCV’s). These vehicles offer more load capacity, which reduces transport costs and thus increases the efficiency and competitiveness of companies and the country. But the tradeoff of LCV’s is their low lateral stability and propensity to roll over, which has been the focus of many studies. Most vehicle stability models do not consider the longitudinal aspects of the vehicle and the road, such as the stiffness of the chassis, the gravity center location, and the longitudinal slope angle of the road. But, the use of three-dimensional models of vehicles allows a more rigorous analysis of vehicle stability. In this context, this study aims to develop a three-dimensional mechanism model representing the last trailer unit of an LCV under an increasing lateral load until it reaches the rollover threshold. The proposed model considers the gravity center movement of the trailer, which is affected by the suspension, tires, fifth-wheel, and the chassis. Davies method has proved to be an important tool in the kinetostatic analysis of mechanisms, and therefore it is employed for the kinetostatic analysis of the three-dimensional mechanism of the trailer.

Building Virtual Driving Environments From Computer-Made Projects

2019 ◽  
pp. 306-320
Author(s):  
Carlos José Campos ◽  
Hugo Filipe Pinto ◽  
João Miguel Leitão ◽  
João Paulo Pereira ◽  
António Fernando Coelho ◽  
...  
Keyword(s):  
Experimental Studies ◽  
3D Models ◽  
Level Of Detail ◽  
Driving Simulation ◽  
Driving Simulators ◽  
The Road ◽  
Terrain Models ◽  
Procedural Method ◽  
Modeling Task ◽  
State Of Art

The virtual environments used in scientific driving simulation experiments require extensive 3D models of road landscapes, correctly modeled and similar to those found in the real world. The modeling task of these environments, addressing the terrain definition and the specific characteristics required by the target applications, may result in a complex and time-consuming process. This chapter presents a procedural method to model large terrain definitions and adjust the roadside landscape to produce well-constructed road environments. The proposed procedural method allows merging an externally modeled road into a terrain definition, providing an integrated generation of driving environments. The road and terrain models are optimized to interactive visualization in real time, by applying most state-of-art techniques like the level of detail selection and spatial hierarchization. The proposed method allows modeling large road environments, with the realism and quality required to perform experimental studies in driving simulators.

scholarly journals Framework for 3D Point Cloud Modelling Aimed at Road Sight Distance Estimations

2019 ◽  
Vol 11 (23) ◽  
pp. 2730
Author(s):  
González-Gómez ◽  
Iglesias ◽  
Rodríguez-Solano ◽  
Castro
Keyword(s):  
Point Cloud ◽  
Three Dimensional ◽  
The Road ◽  
3D Objects ◽  
Sight Distance ◽  
Road Geometry ◽  
Three Dimensional Models ◽  
The Individual ◽  
Periodic Evaluation ◽  
Cloud Modelling

Existing roads require periodic evaluation in order to ensure safe transportation. Estimations of the available sight distance (ASD) are fundamental to make sure motorists have sufficient visibility to perform basic driving tasks. Mobile LiDAR Systems (MLS) can provide these evaluations with accurate three-dimensional models of the road and surroundings. Similarly, Geographic Information System (GIS) tools have been employed to obtain ASD. Due to the fact that widespread GIS formats used to store digital surface models handle elevation as an attribute of location, the presented methodology has separated the representation of ground and aboveground elements. The road geometry and surrounding ground are stored in digital terrain models (DTM). Correspondingly, abutting vegetation, manmade structures, road assets and other roadside elements are stored in 3D objects and placed on top of the DTM. Both the DTM and 3D objects are accurately obtained from a denoised and classified LiDAR point cloud. Based on the consideration that roadside utilities and most manmade structures are well-defined geometric elements, some visual obstructions are extracted and/or replaced with 3D objects from online warehouses. Different evaluations carried out with this method highlight the tradeoff between the accuracy of the estimations, performance and geometric complexity as well as the benefits of the individual consideration of road assets.

Plastic replicas as three-dimensional models of pulps

1975 ◽  
Vol 39 (8) ◽  
pp. 544-546
Author(s):  
HL Wakkerman ◽  
GS The ◽  
AJ Spanauf
Keyword(s):  
Three Dimensional ◽  
Dimensional Models ◽  
Three Dimensional Models

Validation of a Belt Model for Prediction of Hub Forces from a Rolling Tire4

2009 ◽  
Vol 37 (2) ◽  
pp. 62-102 ◽  
Author(s):  
C. Lecomte ◽  
W. R. Graham ◽  
D. J. O’Boy
Keyword(s):  
Internal Pressure ◽  
Equations Of Motion ◽  
Three Dimensional ◽  
Prediction Method ◽  
Analytical Models ◽  
Beam Model ◽  
Impedance Boundary ◽  
Bending Waves ◽  
Tire Rotation ◽  
Three Dimensional Models

Abstract An integrated model is under development which will be able to predict the interior noise due to the vibrations of a rolling tire structurally transmitted to the hub of a vehicle. Here, the tire belt model used as part of this prediction method is first briefly presented and discussed, and it is then compared to other models available in the literature. This component will be linked to the tread blocks through normal and tangential forces and to the sidewalls through impedance boundary conditions. The tire belt is modeled as an orthotropic cylindrical ring of negligible thickness with rotational effects, internal pressure, and prestresses included. The associated equations of motion are derived by a variational approach and are investigated for both unforced and forced motions. The model supports extensional and bending waves, which are believed to be the important features to correctly predict the hub forces in the midfrequency (50–500 Hz) range of interest. The predicted waves and forced responses of a benchmark structure are compared to the predictions of several alternative analytical models: two three dimensional models that can support multiple isotropic layers, one of these models include curvature and the other one is flat; a one-dimensional beam model which does not consider axial variations; and several shell models. Finally, the effects of internal pressure, prestress, curvature, and tire rotation on free waves are discussed.

In Silico Identification and Molecular Characterization of Extracellular Cathepsin L Proteases from Giardia duodenalis

2020 ◽  
Vol 17 (4) ◽  
pp. 342-351
Author(s):  
Sergio A. Durán-Pérez ◽  
José G. Rendón-Maldonado ◽  
Lucio de Jesús Hernandez-Diaz ◽  
Annete I. Apodaca-Medina ◽  
Maribel Jiménez-Edeza ◽  
...  
Keyword(s):  
In Silico ◽  
Cathepsin L ◽  
Three Dimensional ◽  
Giardia Duodenalis ◽  
Evolutionary Genetics ◽  
Extracellular Proteins ◽  
In Silico Identification ◽  
Dimensional Models ◽  
Three Dimensional Models

Background: The protozoan Giardia duodenalis, which causes giardiasis, is an intestinal parasite that commonly affects humans, mainly pre-school children. Although there are asymptomatic cases, the main clinical features are chronic and acute diarrhea, nausea, abdominal pain, and malabsorption syndrome. Little is currently known about the virulence of the parasite, but some cases of chronic gastrointestinal alterations post-infection have been reported even when the infection was asymptomatic, suggesting that the cathepsin L proteases of the parasite may be involved in the damage at the level of the gastrointestinal mucosa. Objective: The aim of this study was the in silico identification and characterization of extracellular cathepsin L proteases in the proteome of G. duodenalis. Methods: The NP_001903 sequence of cathepsin L protease from Homo sapienswas searched against the Giardia duodenalisproteome. The subcellular localization of Giardia duodenaliscathepsin L proteases was performed in the DeepLoc-1.0 server. The construction of a phylogenetic tree of the extracellular proteins was carried out using the Molecular Evolutionary Genetics Analysis software (MEGA X). The Robetta server was used for the construction of the three-dimensional models. The search for possible inhibitors of the extracellular cathepsin L proteases of Giardia duodenaliswas performed by entering the three-dimensional structures in the FINDSITEcomb drug discovery tool. Results: Based on the amino acid sequence of cathepsin L from Homo sapiens, 8 protein sequences were identified that have in their modular structure the Pept_C1A domain characteristic of cathepsins and two of these proteins (XP_001704423 and XP_001704424) are located extracellularly. Threedimensional models were designed for both extracellular proteins and several inhibitory ligands with a score greater than 0.9 were identified. In vitrostudies are required to corroborate if these two extracellular proteins play a role in the virulence of Giardia duodenalisand to discover ligands that may be useful as therapeutic targets that interfere in the mechanism of pathogenesis generated by the parasite. Conclusion: In silicoanalysis identified two proteins in the Giardia duodenalisprotein repertoire whose characteristics allowed them to be classified as cathepsin L proteases, which may be secreted into the extracellular medium to act as virulence factors. Three-dimensional models of both proteins allowed the identification of inhibitory ligands with a high score. The results suggest that administration of those compounds might be used to block the endopeptidase activity of the extracellular cathepsin L proteases, interfering with the mechanisms of pathogenesis of the protozoan parasite Giardia duodenalis.

Handheld Laser Scanner Research

2019 ◽  
Vol 952 (10) ◽  
pp. 47-54
Author(s):  
A.V. Komissarov ◽  
A.V. Remizov ◽  
M.M. Shlyakhova ◽  
K.K. Yambaev
Keyword(s):  
Point Cloud ◽  
Three Dimensional ◽  
Laser Scanner ◽  
Test Site ◽  
Optical Systems ◽  
Advantages And Disadvantages ◽  
Site Survey ◽  
Laser Scanners ◽  
Three Dimensional Models ◽  
The Stability

The authors consider hand-held laser scanners, as a new photogrammetric tool for obtaining three-dimensional models of objects. The principle of their work and the newest optical systems based on various sensors measuring the depth of space are described in detail. The method of simultaneous navigation and mapping (SLAM) used for combining single scans into point cloud is outlined. The formulated tasks and methods for performing studies of the DotProduct (USA) hand-held laser scanner DPI?8X based on a test site survey are presented. The accuracy requirements for determining the coordinates of polygon points are given. The essence of the performed experimental research of the DPI?8X scanner is described, including scanning of a test object at various scanner distances, shooting a test polygon from various scanner positions and building point cloud, repeatedly shooting the same area of the polygon to check the stability of the scanner. The data on the assessment of accuracy and analysis of research results are given. Fields of applying hand-held laser scanners, their advantages and disadvantages are identified.

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