WO2021080332A2 - System for predicting vehicle trajectory by using extended kalman filter in vehicle software defined networking and method therefor, and computer-readable recording medium on which program for performing method is recorded - Google Patents

System for predicting vehicle trajectory by using extended kalman filter in vehicle software defined networking and method therefor, and computer-readable recording medium on which program for performing method is recorded Download PDF

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WO2021080332A2
WO2021080332A2 PCT/KR2020/014441 KR2020014441W WO2021080332A2 WO 2021080332 A2 WO2021080332 A2 WO 2021080332A2 KR 2020014441 W KR2020014441 W KR 2020014441W WO 2021080332 A2 WO2021080332 A2 WO 2021080332A2
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vehicle
model
constant
equation
kalman filter
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Korean (ko)
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WO2021080332A3 (en
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송왕철
아바스 무하마드타히르
지브란 무하마드알리
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제주대학교 산학협력단
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    • GPHYSICS
    • G08SIGNALLING
    • G08GTRAFFIC CONTROL SYSTEMS
    • G08G1/00Traffic control systems for road vehicles
    • G08G1/01Detecting movement of traffic to be counted or controlled
    • G08G1/0104Measuring and analyzing of parameters relative to traffic conditions
    • G08G1/0137Measuring and analyzing of parameters relative to traffic conditions for specific applications
    • GPHYSICS
    • G06COMPUTING; CALCULATING OR COUNTING
    • G06QINFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES; SYSTEMS OR METHODS SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES, NOT OTHERWISE PROVIDED FOR
    • G06Q10/00Administration; Management
    • G06Q10/04Forecasting or optimisation specially adapted for administrative or management purposes, e.g. linear programming or "cutting stock problem"
    • GPHYSICS
    • G06COMPUTING; CALCULATING OR COUNTING
    • G06QINFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES; SYSTEMS OR METHODS SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES, NOT OTHERWISE PROVIDED FOR
    • G06Q10/00Administration; Management
    • G06Q10/06Resources, workflows, human or project management; Enterprise or organisation planning; Enterprise or organisation modelling
    • G06Q10/063Operations research, analysis or management
    • G06Q10/0637Strategic management or analysis, e.g. setting a goal or target of an organisation; Planning actions based on goals; Analysis or evaluation of effectiveness of goals
    • G06Q10/06375Prediction of business process outcome or impact based on a proposed change
    • GPHYSICS
    • G08SIGNALLING
    • G08GTRAFFIC CONTROL SYSTEMS
    • G08G1/00Traffic control systems for road vehicles
    • G08G1/01Detecting movement of traffic to be counted or controlled
    • G08G1/0104Measuring and analyzing of parameters relative to traffic conditions
    • G08G1/0108Measuring and analyzing of parameters relative to traffic conditions based on the source of data
    • G08G1/012Measuring and analyzing of parameters relative to traffic conditions based on the source of data from other sources than vehicle or roadside beacons, e.g. mobile networks
    • GPHYSICS
    • G08SIGNALLING
    • G08GTRAFFIC CONTROL SYSTEMS
    • G08G1/00Traffic control systems for road vehicles
    • G08G1/01Detecting movement of traffic to be counted or controlled
    • G08G1/0104Measuring and analyzing of parameters relative to traffic conditions
    • G08G1/0125Traffic data processing
    • G08G1/0129Traffic data processing for creating historical data or processing based on historical data
    • GPHYSICS
    • G08SIGNALLING
    • G08GTRAFFIC CONTROL SYSTEMS
    • G08G1/00Traffic control systems for road vehicles
    • G08G1/01Detecting movement of traffic to be counted or controlled
    • G08G1/017Detecting movement of traffic to be counted or controlled identifying vehicles
    • GPHYSICS
    • G08SIGNALLING
    • G08GTRAFFIC CONTROL SYSTEMS
    • G08G1/00Traffic control systems for road vehicles
    • G08G1/01Detecting movement of traffic to be counted or controlled
    • G08G1/052Detecting movement of traffic to be counted or controlled with provision for determining speed or overspeed

Definitions

  • the present invention relates to a technology capable of stabilizing future vehicle networking by calculating the positions of vehicles on a road in a certain area in an edge cloud.
  • Vehicle group driving consists of a top-level vehicle driven directly by the driver and a number of sub-vehicles following it.
  • the lower vehicles may be autonomous driving without driver intervention.
  • Vehicle group driving like this can be said to be an intermediate step toward fully autonomous driving, and technology development is underway in advanced countries such as Europe.
  • the SARTRE (Safe Road Trains for the Environment) project was researched as a part of EC FP7, and developed a system to safely and conveniently perform vehicle platoon or vehicle group driving when driving on general public highways.
  • the system provides a safe vehicle group driving service while interoperating with other traffic on the highway.
  • the system provides autonomous driving for lower-level vehicles, except for top-level vehicles driven by individual drivers.
  • SDN Software Defined Networking
  • ONF OpenFlow
  • ETSI European Telecommunications Standards Institute
  • IETF Internet Engineering Task Force
  • NFV Network Function Virtualization
  • VM Virtual Machine
  • VM Virtual Machine
  • various network devices such as routers, load balancers, firewalls, intrusion prevention, and virtual private networks, can be implemented in software on a general server, thereby avoiding the vendor dependence of network configuration. This is because expensive dedicated equipment can be replaced with general-purpose hardware and dedicated software. Furthermore, it has the advantage of being able to quickly respond to changes in traffic as well as reducing equipment operating costs.
  • SDN Software Defined Networking
  • SDN technology is characterized by separating the functions of a complex control plane from a data plane.
  • the complex functions of the control plane are processed by software, and the data plane performs only simple functions indicated by the control plane, such as forwarding, ignoring, and changing network packets.
  • NFV and SDN are separate technologies, they can work complementarily. This is because various network functions implemented in software by NFV can be efficiently controlled using SDN.
  • SDN is based on two basic principles.
  • SDN must perform Software Defined Forwarding.
  • Software-defined forwarding means that the data forwarding function handled by hardware in the switch/router must be controlled through an open interface and software.
  • SDN aims at Global Management Abstraction. SDN enables more advanced network management through abstraction.
  • this abstraction may include a response to an event (such as a topology change or a new flow input) based on the state of the entire network, and the ability to control network elements.
  • an event such as a topology change or a new flow input
  • the vehicle's trajectory prediction is not deterministic.
  • V2V Vehicle to Vehicle
  • V2I Vehicle to Infrastructure, communication between vehicle and roadside base stations
  • the present invention was conceived to solve the above-described problem, and in an embodiment of the present invention, an Extended Kalman Filter (EKF; extended Kalman filter) incorporating an Interacting Multiple Model (IMM) is used. It is possible to provide a method of predicting the vehicle position, and through this, it is possible to provide a system that can stabilize the networking of vehicles in the future by calculating the positions of vehicles on roads in a certain area in the edge cloud.
  • EKF Extended Kalman Filter
  • IMM Interacting Multiple Model
  • the navigation map contains most of the information on the road, information on the number of lanes on the road can be known, it is possible to correlate it with the vehicle speed to present a vehicle turn model.
  • a system for tracking the location of a vehicle including a device capable of Software Defined Networking (SDN) under an edge crowd, tracking the location of the vehicle SDN control device installed in a vehicle applying the edge crowd to a specific target area;
  • An edge controller that receives driving information including vehicle speed, position, and acceleration generated in the vehicle from the SDN control device;
  • the edge controller based on the driving information provided by the driving means, calculates and accumulates a probability density function by an Interacting Multiple Model (IMM) unit to calculate an expected position of the vehicle.
  • IMM Interacting Multiple Model
  • EKF Extended Kalman Filter
  • IMM Interacting Multiple Model
  • the navigation map contains most of the information on the road, information on the number of lanes on the road can be known, so it is possible to correlate it with the vehicle speed and present a turn model.
  • the least stable part of vehicle communication is due to the situation in which the communication link between vehicles needs to be changed from time to time due to the mobility of the vehicle. If the location of the vehicle is stably predicted, the controller controls the limit of the wireless network to prevent loss of traffic. It will be possible.
  • FIG. 1 is a block diagram showing a vehicle trajectory prediction system using an extended Kalman filter in vehicle software defined networking implemented according to an embodiment of the present invention
  • FIG. 2 is a configuration centered on an edge controller among the components of FIG. 1 It is a conceptual diagram showing together.
  • FIG. 3 is an application conceptual diagram of implementing a vehicle trajectory prediction system using an extended Kalman filter in vehicle software defined networking according to an embodiment of the present invention.
  • the configuration provided in the embodiment of the present invention proposes a method of predicting a vehicle position on a road using an Extended Kalman Filter (EKF; Extended Kalman Filter) incorporating an Interacting Multiple Model (IMM),
  • EKF Extended Kalman Filter
  • IMM Interacting Multiple Model
  • FIG. 1 is a block diagram showing a vehicle trajectory prediction system (hereinafter referred to as'the present invention') using an extended Kalman filter in a vehicle software defined networking implemented according to an embodiment of the present invention
  • FIG. 2 is FIG. It is a conceptual diagram showing the configuration centered on the edge controller among the components of.
  • FIG. 3 is an application conceptual diagram of implementing a vehicle trajectory prediction system using an extended Kalman filter in vehicle software defined networking according to an embodiment of the present invention.
  • the present invention provides a system for tracking the location of a vehicle including a device capable of Software Defined Networking (SDN) under an edge crowd.
  • SDN control device 110, 120, 130
  • operation information including vehicle speed, position, and acceleration generated in the vehicle is transmitted from the SDN control device. It may be configured to include an edge controller (EC).
  • EC edge controller
  • the edge controller calculates the probability density function by the IMM (Interacting Multiple Model) unit 210 based on the operation information provided from the SDN control device of the vehicle.
  • an Extended Kalman Filter (EKF) module 200 that accumulates and calculates an expected position of the vehicle.
  • the SDN networking technology is implemented in vehicle communication, and communication is possible through this, and because one SDN control device cannot control the entire network, the edge cloud for each region When is applied, an environment in which information transmission and calculation for roads in the area is possible is premised.
  • the SDN controller can perform much more stable communication control.
  • the least stable part of vehicle communication is due to the situation in which the communication link between vehicles must be changed from time to time due to the mobility of the vehicle. If the position of the vehicle is stably predicted by the system according to the present invention, the controller can overcome the limitations of the wireless network. Beyond that, it becomes controllable so that no traffic loss occurs.
  • the edge controller (EC) of the present invention includes an Interacting Multiple Model (IMM) unit based on the driving information provided by the driving means. It includes an extended Kalman filter (EKF) module 210 that calculates and accumulates the probability density function by 210 to calculate the predicted position of the vehicle, and provides a predicted model for predicted dynamic information. It can be configured to include a prediction model providing unit 220.
  • IMM Interacting Multiple Model
  • EKF extended Kalman filter
  • the prediction model providing unit derives and provides five KF (Kalman filter) models in consideration of all possible situations of vehicle movement.
  • Each of these models is set to fit a specific set of scenarios in which the vehicle can be found, i.e. a constant jerk model, a constant acceleration model, a constant speed model, a fixed position model, and a vehicle turning model.
  • the prediction model provided by the prediction model providing unit 220 may be provided as a total of five models according to the following ⁇ Equation 1 ⁇ to ⁇ Equation 5 ⁇ . (Vehicle position (Xv), vehicle speed (Vv), and distance from the nearest intersection in the direction of vehicle movement (Dv))
  • Constant position model CL describes a scenario where the vehicle does not move or the speed is '0'.
  • Constant speed model represents the situation of the vehicle when the vehicle with the current position Xv t of the vehicle and the distance DvI t at the nearest intersection in the vehicle movement direction moves to the registration Vvt.
  • is the processing noise covariance (process). noise covariance), which is a constant.
  • Constant acceleration model (CA) represents the situation of the vehicle when the vehicle moves with a constant acceleration (a).
  • a constant acceleration
  • the state of the vehicle is considered to be in a moving state with a flexible position
  • ⁇ t is the previous period.
  • the variable of (t-1) means the statistics of the previous period
  • is the process noise covariance, which is a constant.
  • Constant jerk model represents a situation when a vehicle moves at a constant acceleration with a change in acceleration for a certain period of time.
  • VT Vehicle's Turning Model
  • the Kalman filter of the present invention operates with a feedback approach, first processes data at time T, and receives feedback from the vehicle's SDN controller in terms of GPS measurement including vehicle speed, position and acceleration. State vectors are formed using these parameters, which are decomposed into x and y components, respectively.
  • Equation 1 the vehicle position (Xv), the vehicle speed (Vv), and from the nearest intersection in the vehicle movement direction are Three parameters of distance (Dv) were considered.
  • every parameter has two components, x and y, i.e. the position of the x and y coordinates, and the normal and tangential acceleration.
  • the formula for vehicle position correction and prediction using KF is as follows.
  • H is the Jacobian of the parametric model
  • P is the prediction error covariance
  • R is the noise covariance of the model
  • K is the Kalman gain.
  • x represents the prediction of the vehicle's condition at time k-1
  • k represents the current time
  • A represents Jacobian's system model for the current state.
  • the matrix ′P′ represents the estimated error covariance, and then ′R′ (measured noise ) Are used together with'K' (covariance to estimate the value of Kalman gain) and'H' (Jacobia matrix).
  • the matrix'PP is a data set, describing the association in the observation error between all pairs at the vertical level. In our case, the error covariance for all proposed models is estimated by mapping the filter itself.
  • the probability density function (pdf) is calculated and the most probable model is selected to predict the future position of the vehicle. This is done by the IMM algorithm that accumulates the probability of occurrence for each model using the Markov model, and the final transition metric is defined as all probabilities.
  • the IMM unit predicts the next point through the feedback processor as follows.
  • Step 1 of transmitting driving information including acceleration can be performed.
  • the second step of calculating and accumulating the function to calculate the expected position of the vehicle may be performed.
  • the second step is, in the IMM (Interacting Multiple Model; interactive multiple model program) unit 210, calculates an occurrence probability for a predictive model modeled on the movement of the vehicle, and applies the calculated probability to the corresponding model.
  • the step of identifying the dominance of vehicle position prediction through may be performed.
  • the IMM unit 210 When the IMM unit 210 identifies the dominant model (from the models according to Equations 1 to 5) through the feedback process, the probability for each iteration is continuously recalculated and calculated from the previous iteration. A new probability value is weighted with respect to the generated probability value, and the probability of each model is calculated through the state transition matrix according to Equation 7 below, based on the calculated information. In this process, the IMM unit 210 calculates a probability density function (pdf) using a Markov (Markov) chain model, and then calculates a cumulative probability for each model.
  • PDF probability density function
  • the current vehicle position is estimated using a constant position model (CL), and then the CL model is re-applied to find the vehicle position in the future, or a probability of applying another model is calculated.
  • CL constant position model
  • the IMM unit calculates the probability density function (pdf) using the Markov chain model and then calculates the probability.
  • PDF probability density function
  • FIG. 3 is a conceptual diagram showing the application of the system (FIGS. 1 and 2) according to the present invention.
  • SD-IoV Soft-Defined Internet
  • vehicles on the road search cellular networks to transmit information dynamically, and RSU (Road Side Unit) and RSU (Road Side Unit) to communicate data between vehicles. Unit).
  • the extended Kalman filter module in the present invention is used for vehicle prediction in the edge controller (EC).
  • the Kalman filter (KF) provides an efficient recursive method for predicting the future state of a vehicle using a series of mathematical equations.
  • the Kalman filter (KF) with a multi-model approach is a single model, but avoids complex models. Scenarios are divided into sub-scenarios according to each KF model because more accurate results are obtained than scenarios with high complexity. Scenarios for such a vehicle are a non-powered vehicle, a constant acceleration vehicle, a vehicle with a constant speed, and a variable acceleration vehicle (five models proposed in the present invention).
  • the predicted position of the vehicle is calculated by calculating and accumulating a probability density function by an IMM (Interacting Multiple Model) unit based on driving information through five models. It is done to calculate.
  • IMM Interacting Multiple Model
  • the present invention introduces a new technique to the soft-definition Internet of a vehicle in order to estimate the location of a vehicle, so that a new route can be secured in advance when a vehicle enters a new road section with another neighboring vehicle.
  • the five position prediction models proposed in the present invention can predict the vehicle position not only on a straight path, but also on a random and curved path.
  • V2V vehicle-to-vehicle communication
  • V2V vehicle-to-vehicle communication
  • the present invention can provide a model for predicting the position of a vehicle, which is essential for stabilizing such vehicle-to-vehicle communication, and thus, if the SDN controller is combined with a direct stabilization model for vehicle communication in the future, it is considered to have very great competitiveness.
  • the system and method according to the present invention are intended to bring about stabilization of vehicle communication by estimating the location of the vehicle, and can be performed in the edge cloud.
  • the vehicle position prediction implementation solution function performed through each model implemented through the extended Kalman filter module provided by the present invention can be programmed and provided, and in the present invention, a computer-readable recording of such an application program is recorded.
  • the medium can be executed using a computer or a mobile communication terminal (eg, a smartphone or a tablet PC).
  • a computer or a mobile communication terminal eg, a smartphone or a tablet PC.
  • such an application program may be installed on a hard disk of a computer, installed on a CD-ROM or a DVD-ROM, or installed on a USB memory and executed.
  • it can be installed and executed in various playback devices.
  • the communication network to which the system of the present invention is applied is a network capable of wired and wireless communication, and a mobile communication network installed and operated by a communication company (including 3G network, 4G network, 5G network, WiBro network, LTE network), Internet network/ It may include a public switched telephone network (PSTN) network.
  • a communication company including 3G network, 4G network, 5G network, WiBro network, LTE network
  • Internet network may include a public switched telephone network (PSTN) network.
  • PSTN public switched telephone network
  • the configuration and execution operation of the Kalman filter module applied to the present invention and implemented in the edge controller may be represented by functional block configurations and various processing steps. These functional blocks may be implemented with various numbers of hardware or/and software configurations that perform specific functions.
  • the present invention provides integrated circuit configurations such as memory, processing, logic, and look-up tables, which can execute various functions by controlling one or more microprocessors or by other control devices. Can be adopted.
  • the present invention includes various algorithms implemented with a combination of data structures, processes, routines or other programming constructs, including C, C++. , Java, assembler, or the like may be implemented in a programming or scripting language. Functional aspects can be implemented with an algorithm running on one or more processors.
  • the present invention may employ conventional techniques for electronic environment setting, signal processing, and/or data processing. Terms such as “mechanism”, “element”, “means”, and “configuration” may be used broadly, and are not limited to mechanical and physical configurations. The term may include a meaning of a series of routines of software in connection with a processor or the like.

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Abstract

According to an embodiment of the present invention, a network slice selection function for identifying and selecting a network slice instance for an interaction with a mobility management entity (MME)/access mobility function (AMF) may be provided by implementing a function of selecting a correct network slice instance appropriately matching a request of a user terminal in a 5G architecture (23.501 3GGP technical specification), in particular, finding out a current state of a network via communication with a VNF orchestration platform.

Description

차량 소프트웨어 정의 네트워킹에서 확장 칼만필터를 이용하는 차량 궤적 예측시스템 및 그 방법, 그 방법을 수행하는 프로그램이 기록된 컴퓨터 판독이 가능한 기록매체Vehicle trajectory prediction system using an extended Kalman filter in vehicle software-defined networking, its method, and a computer-readable recording medium in which a program that performs the method is recorded
본 발명은 에지 클라우드에서 일정 지역의 도로에 있는 차량들의 위치를 계산함으로써, 향후 차량의 네트워킹에 안정화를 줄 수 있는 기술에 대한 것이다.The present invention relates to a technology capable of stabilizing future vehicle networking by calculating the positions of vehicles on a road in a certain area in an edge cloud.
차량 그룹 주행은 운전자가 직접 운전하는 최상위 차량과 그 뒤를 따르는 다수의 하위 차량들로 이루어진다. 이때, 하위 차량들은 운전자 개입 없이 자율 주행(autonomous driving)할 수도 있다. 이와 같은 차량 그룹 주행은 완전 자율 주행으로 가는 중간 단계라 할 수 있으며, 유럽 등 선진국에서 기술 개발이 진행되고 있다.Vehicle group driving consists of a top-level vehicle driven directly by the driver and a number of sub-vehicles following it. In this case, the lower vehicles may be autonomous driving without driver intervention. Vehicle group driving like this can be said to be an intermediate step toward fully autonomous driving, and technology development is underway in advanced countries such as Europe.
SARTRE (Safe Road Trains for the Environment) 프로젝트는 EC FP7 일환으로 연구가 진행되었으며, 일반적인 공공 고속도로에서 운행함에 있어서 안전하고 편리하게 군집 주행(vehicle platoon) 또는 차량 그룹 주행을 수행하기 위한 시스템을 개발하였다.The SARTRE (Safe Road Trains for the Environment) project was researched as a part of EC FP7, and developed a system to safely and conveniently perform vehicle platoon or vehicle group driving when driving on general public highways.
상기 시스템은 고속도로에서 다른 트래픽과 상호 동작하면서 안전한 차량 그룹 주행 서비스를 제공한다. 특히, 이 시스템은 개인 운전자에 의해 운전하는 최상위 차량을 제외하고, 하위 차량들은 자율 주행을 제공한다.The system provides a safe vehicle group driving service while interoperating with other traffic on the highway. In particular, the system provides autonomous driving for lower-level vehicles, except for top-level vehicles driven by individual drivers.
소프트웨어 정의 네트워킹(Software Defined Networking, SDN)은 새로운 네트워크 구조 또는 새로운 패러다임이며, 네트워크를 제어평면과 전달평면으로 분리한다. 이를 구현한 기술 중에 하나가 OpenFlow이다. OpenFlow 관련 표준을 개발하는 ONF(Open Networking Foundation)가 최근까지 가장 영향력이 있었지만, 최근에는 ETSI(European Telecommunications Standards Institute), IETF(Internet Engineering Task Force) 등에서 NFV(Network Function Virtualization)에 관한 연구가 활발하다. 최근 네트워크 기능 가상화 기술은 하드웨어 위주였던 네트워크 아키텍처 전반에 새로운 변화를 일으키고 있다. 네트워크 기능 가상화 (NFV: Network Function Virtualization), 즉 NFV는 네트워크의 구성 요소인 하드웨어와 소프트웨어를 분리하고, 물리적인 네트워크 설비의 기능을 가상화 하여 VM(Virtual Machine) 서버, 범용 프로세서를 탑재한 하드웨어, 클라우딩 컴퓨터에서 실행하는 개념이다. 이에 따르면 라우터, 로드 밸런서, 방화벽, 침입 방지, 가상 사설망 등 다양한 네트워크 장비들을 일반 서버에서 소프트웨어로 구현할 수 있어 네트워크 구성의 벤더 의존성에서 벗어날 수 있다. 값비싼 전용 장비를 범용 하드웨어와 전용 소프트웨어로 대체할 수 있기 때문이다. 나아가 장비 운영 비용 절감은 물론 트래픽 변화 등에 신속하게 대처할 수 있는 장점이 있다.Software Defined Networking (SDN) is a new network structure or new paradigm, and separates the network into a control plane and a transfer plane. One of the technologies implementing this is OpenFlow. The Open Networking Foundation (ONF), which develops OpenFlow-related standards, has been the most influential until recently, but recently, research on NFV (Network Function Virtualization) has been actively conducted by ETSI (European Telecommunications Standards Institute) and IETF (Internet Engineering Task Force). . Recently, network function virtualization technology has brought about a new change in the overall network architecture, which was mainly hardware-oriented. Network Function Virtualization (NFV), that is, NFV separates hardware and software components of a network, and virtualizes the functions of physical network facilities to create a VM (Virtual Machine) server, hardware equipped with a general-purpose processor, and cloud. It is a concept running on a Ding computer. According to this, various network devices, such as routers, load balancers, firewalls, intrusion prevention, and virtual private networks, can be implemented in software on a general server, thereby avoiding the vendor dependence of network configuration. This is because expensive dedicated equipment can be replaced with general-purpose hardware and dedicated software. Furthermore, it has the advantage of being able to quickly respond to changes in traffic as well as reducing equipment operating costs.
한편 소프트웨어 정의 네트워킹(Software Defined Networking; SDN), 즉 SDN 기술은 복잡한 컨트롤 플레인(control plane)의 기능을 데이터 플레인(data plane)과 분리하는 것이 특징이다. 이에 따르면 컨트롤 플레인의 복잡한 기능을 소프트웨어로 처리하고, 데이터 플레인은 네트워크 패킷의 전달, 무시, 변경 등 컨트롤 플레인이 지시하는 단순한 기능만을 수행하게 된다. 이러한 기술을 적용하면 복잡한 하드웨어의 제약 없이 소프트웨어로 새로운 네트워크 기능을 개발할 수 있으며, 동시에 이전 네트워크 구조에서 불가능했던 다양한 시도를 할 수 있게 되었다.Meanwhile, Software Defined Networking (SDN), that is, SDN technology, is characterized by separating the functions of a complex control plane from a data plane. According to this, the complex functions of the control plane are processed by software, and the data plane performs only simple functions indicated by the control plane, such as forwarding, ignoring, and changing network packets. By applying these technologies, it is possible to develop new network functions with software without complicated hardware constraints, and at the same time, various attempts that were not possible in the previous network structure became possible.
상기 NFV와 SDN은 별개의 기술이지만 상호 보완적으로 작용할 수 있다. NFV에 의해 소프트웨어로 구현된 각종 네트워크 기능을 SDN을 이용하여 효율적으로 제어할 수 있기 때문이다.Although the NFV and SDN are separate technologies, they can work complementarily. This is because various network functions implemented in software by NFV can be efficiently controlled using SDN.
SDN은 두 가지의 기본적인 원칙을 바탕으로 하고 있다.SDN is based on two basic principles.
첫째로, SDN은 소프트웨어 정의 포워딩(Software Defined Forwarding)을 해야 한다. 소프트웨어 정의 포워딩은 스위치/라우터에서 하드웨어가 처리하는 데이터 포워딩 기능이 반드시 개방형 인터페이스와 소프트웨어를 통해서 제어되어야만 한다는 것을 의미한다.First, SDN must perform Software Defined Forwarding. Software-defined forwarding means that the data forwarding function handled by hardware in the switch/router must be controlled through an open interface and software.
둘째로, SDN이 글로벌 관리 추상화(Global Management Abstraction)를 목표로 한다. SDN은 추상화를 통해 보다 진보된 네트워크 관리를 가능하게 한다.Second, SDN aims at Global Management Abstraction. SDN enables more advanced network management through abstraction.
예를 들면, 이런 추상화는 전체 네트워크의 상태에 기반하여 이벤트(토폴로지 변화 또는 새로운 플로우 입력등)에 상응하는 반응, 그리고 네트워크 요소를 제어할 수 있는 기능 등을 포함할 수 있다.For example, this abstraction may include a response to an event (such as a topology change or a new flow input) based on the state of the entire network, and the ability to control network elements.
자율주행 차량에 대한 관심이 높아지면서, 자연스럽게 차량 통신에 대한 관심도 높다. 다양한 종류의 데이터가 전송되어야 하는 차량 네트워크에 안정도 역시 아주 큰 관심사이지만, 도로에서 차량의 접속은 그 이동성으로 인해서, 오랫동안 차량간 통신에 대한 연구가 이뤄져 있지만, 그 통신 안정성을 더 개선해야할 필요가 있다. As interest in autonomous vehicles increases, interest in vehicle communication naturally also increases. Stability is also of great interest in vehicle networks in which various types of data are to be transmitted, but because of its mobility, connection of vehicles on the road has been studied for a long time on vehicle-to-vehicle communication, but there is a need to further improve the communication stability. .
차량의 움직임은 전적으로 차량 운전자의 습관과 판단에 따라 달라지기 때문에, 차량의 궤적(trajectory) 예측은 결정적(deterministic)이지 않다. Because the vehicle's movement is entirely dependent on the vehicle driver's habits and judgments, the vehicle's trajectory prediction is not deterministic.
나아가 여러 경우에 있어서, 차량의 궤적(trajectory) 예측은 일정 속도로 일정 가속으로 차량이 운행하는 경우에 잘 예측하는 모델들만으로 제한되어져 왔다 또한, 방향전환(turn) 모델은 차량 위치의 예상치 못하는 변화를 주는 것이기 때문에 결과적으로 V2V(V2V, Vehicle to Vehicle, 차량 간 통신) 및 V2I(V2I, Vehicle to Infrastructure, 차량과 노변 기지국 간 통신) 통신의 실패를 가져오는 문제로 거의 고려되지 않았다.Furthermore, in many cases, vehicle trajectory prediction has been limited only to models that predict well when the vehicle operates at a constant acceleration at a constant speed. In addition, the turn model prevents unexpected changes in the vehicle position. As a result, V2V (V2V, Vehicle to Vehicle, vehicle-to-vehicle communication) and V2I (V2I, Vehicle to Infrastructure, communication between vehicle and roadside base stations) were hardly considered as a problem causing communication failure.
본 발명은 상술한 문제를 해결하기 위하여 안출된 것으로, 본 발명의 실시예에서는 Interacting Multiple Model (IMM; 상호작용 다수모델 프로그램)을 통합한 Extended Kalman Filter (EKF; 확장 칼만필터)를 이용하여 도로상의 차량 위치를 예측하는 방법을 제공할 수 있으며, 이를 통해 에지클라우드에서 일정 지역의 도로에 있는 차량들의 위치를 계산함으로써, 향후 차량의 네트워킹에 안정화를 줄 수 있도록 하는 시스템을 제공할 수 있도록 한다.The present invention was conceived to solve the above-described problem, and in an embodiment of the present invention, an Extended Kalman Filter (EKF; extended Kalman filter) incorporating an Interacting Multiple Model (IMM) is used. It is possible to provide a method of predicting the vehicle position, and through this, it is possible to provide a system that can stabilize the networking of vehicles in the future by calculating the positions of vehicles on roads in a certain area in the edge cloud.
또한, 본 발명에서는 네비게이션 지도가 도로의 대부분의 정보를 갖고 있어서 도로의 차선의 갯수 정보를 알 수 있기 때문에 그것과 차량 속도를 연관지어서, 차량의 방향전환(turn) 모델을 제시할 수 있다In addition, in the present invention, since the navigation map contains most of the information on the road, information on the number of lanes on the road can be known, it is possible to correlate it with the vehicle speed to present a vehicle turn model.
상술한 과제를 해결하기 위해, 본 발명의 실시예에서는, 에지 크라우드하에서, SDN(Software Defined Networking ;소프트웨어 정의 네트워킹)이 가능한 장치를 구비하는 차량의 위치를 추적하는 시스템에 있어서, 차량의 위치의 추적 대상이 되는 특정 지역에 에지 크라우드를 적용하는 차량에 설치되는 SDN 제어장치; 상기 차량에서 발생하는 차량 속도, 위치 및 가속도를 포함하는 운행정보를 상기 SDN 제어장치로부터 전송받는 에지 제어기(Edge Controller); 상기 에지 제어기는, 상기 운행수단에서 제공되는 상기 운행정보를 바탕으로, IMM(Interacting Multiple Model; 상호작용 다수모델 프로그램)부에 의해 확률밀도함수를 계산하고 누적하여 차량의 예상 위치를 산출하는 확장 칼만필터(Extended Kalman Filter; EKF)모듈;를 포함하는 차량 소프트웨어 정의 네트워킹에서 확장 칼만필터를 이용하는 차량 궤적 예측시스템을 제공할 수 있도록 한다.In order to solve the above-described problem, in an embodiment of the present invention, in a system for tracking the location of a vehicle including a device capable of Software Defined Networking (SDN) under an edge crowd, tracking the location of the vehicle SDN control device installed in a vehicle applying the edge crowd to a specific target area; An edge controller that receives driving information including vehicle speed, position, and acceleration generated in the vehicle from the SDN control device; The edge controller, based on the driving information provided by the driving means, calculates and accumulates a probability density function by an Interacting Multiple Model (IMM) unit to calculate an expected position of the vehicle. It is possible to provide a vehicle trajectory prediction system using an extended Kalman filter in vehicle software defined networking including a filter (Extended Kalman Filter; EKF) module.
본 발명의 실시예에 따르면, Interacting Multiple Model (IMM; 상호작용 다수모델 프로그램)을 통합한 Extended Kalman Filter (EKF; 확장 칼만필터)를 이용하여 도로상의 차량 위치를 예측하는 방법을 제공할 수 있으며, 이를 통해 에지 클라우드에서 일정 지역의 도로에 있는 차량들의 위치를 계산함으로써, 향후 차량의 네트워킹에 안정화를 줄 수 있도록 하는 효과가 있다.According to an embodiment of the present invention, it is possible to provide a method of predicting a vehicle position on a road by using an Extended Kalman Filter (EKF; Extended Kalman Filter) incorporating an Interacting Multiple Model (IMM), Through this, by calculating the positions of vehicles on roads in a certain area in the edge cloud, there is an effect of stabilizing future vehicle networking.
또한, 본 발명에서는 네비게이션 지도가 도로의 대부분의 정보를 갖고 있어서 도로의 차선의 갯수 정보를 알 수 있기 때문에 그것과 차량 속도를 연관지어서, turn 모델을 제시할 수 있다.In addition, in the present invention, since the navigation map contains most of the information on the road, information on the number of lanes on the road can be known, so it is possible to correlate it with the vehicle speed and present a turn model.
차량 통신에서 가장 안정성이 떨어지는 부분은 차량의 이동성 때문에 차량 간의 통신 링크가 수시로 바뀌어야 하는 상황 때문인데, 차량의 위치가 안정적으로 예측이 된다면, 제어기가 무선망의 한계를 넘어서, 트래픽 유실이 일어나지 않도록 제어 가능할 것이다.The least stable part of vehicle communication is due to the situation in which the communication link between vehicles needs to be changed from time to time due to the mobility of the vehicle.If the location of the vehicle is stably predicted, the controller controls the limit of the wireless network to prevent loss of traffic. It will be possible.
도 1은 이러한 본 발명의 실시예에 따라 구현되는 차량 소프트웨어 정의 네트워킹에서 확장 칼만필터를 이용하는 차량 궤적 예측시스템을 도시한 블록도이며, 도 2는 도 1의 구성요소 중 에지 제어기를 중심으로 하는 구성을 함께 도시한 개념도이다. 1 is a block diagram showing a vehicle trajectory prediction system using an extended Kalman filter in vehicle software defined networking implemented according to an embodiment of the present invention, and FIG. 2 is a configuration centered on an edge controller among the components of FIG. 1 It is a conceptual diagram showing together.
도 3은 본 발명의 실시예에 차량 소프트웨어 정의 네트워킹에서 확장 칼만필터를 이용하는 차량 궤적 예측시스템을 구현하는 적용 개념도이다.3 is an application conceptual diagram of implementing a vehicle trajectory prediction system using an extended Kalman filter in vehicle software defined networking according to an embodiment of the present invention.
본 발명의 이점 및 특징, 그리고 그것들을 달성하는 방법은 첨부되는 도면과 함께 상세하게 후술되는 실시예를 참조하면 명확해질 것이다. 그러나, 본 발명은 이하에서 개시되는 실시예로 한정되는 것이 아니라 서로 다른 다양한 형태로 구현될 것이다.Advantages and features of the present invention, and a method of achieving them will become apparent with reference to embodiments to be described later in detail together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in a variety of different forms.
본 명세서에서 본 실시예는 본 발명의 개시가 완전하도록 하며, 본 발명이 속하는 기술 분야에서 통상의 지식을 가진 자에게 발명의 범주를 완전하게 알려주기 위해 제공되는 것이다. 그리고 본 발명은 청구항의 범주에 의해 정의될 뿐이다. 따라서, 몇몇 실시예에서, 잘 알려진 구성 요소, 잘 알려진 동작 및 잘 알려진 기술들은 본 발명이 모호하게 해석되는 것을 피하기 위하여 구체적으로 설명되지 않는다. In the present specification, the present embodiment is provided to complete the disclosure of the present invention, and to fully inform the scope of the invention to those of ordinary skill in the art to which the present invention pertains. And the invention is only defined by the scope of the claims. Accordingly, in some embodiments, well-known components, well-known operations, and well-known techniques have not been described in detail in order to avoid obscuring interpretation of the present invention.
본 발명의 실시예에서 제공되는 구성은 Interacting Multiple Model (IMM; 상호작용 다수모델 프로그램)을 통합한 Extended Kalman Filter (EKF; 확장 칼만필터)를 이용하여 도로상의 차량 위치를 예측하는 방법을 제시하고, 에지 클라우드에서 일정 지역의 도로에 있는 차량들의 위치를 계산함으로써, 향후 차량의 네트워킹에 안정화를 줄 수 있는 방안을 구현하는 것을 요지로 한다.The configuration provided in the embodiment of the present invention proposes a method of predicting a vehicle position on a road using an Extended Kalman Filter (EKF; Extended Kalman Filter) incorporating an Interacting Multiple Model (IMM), The point is to implement a method that can stabilize the networking of vehicles in the future by calculating the positions of vehicles on the road in a certain area in the edge cloud.
도 1은 이러한 본 발명의 실시예에 따라 구현되는 차량 소프트웨어 정의 네트워킹에서 확장 칼만필터를 이용하는 차량 궤적 예측시스템(이하, '본 발명'이라 한다.)을 도시한 블록도이며, 도 2는 도 1의 구성요소 중 에지 제어기를 중심으로 하는 구성을 함께 도시한 개념도이다. 1 is a block diagram showing a vehicle trajectory prediction system (hereinafter referred to as'the present invention') using an extended Kalman filter in a vehicle software defined networking implemented according to an embodiment of the present invention, and FIG. 2 is FIG. It is a conceptual diagram showing the configuration centered on the edge controller among the components of.
도 3은 본 발명의 실시예에 차량 소프트웨어 정의 네트워킹에서 확장 칼만필터를 이용하는 차량 궤적 예측시스템을 구현하는 적용 개념도이다.3 is an application conceptual diagram of implementing a vehicle trajectory prediction system using an extended Kalman filter in vehicle software defined networking according to an embodiment of the present invention.
도 1 내지 도 3을 참조하며 보면, 본 발명은, 에지 크라우드 하에서, SDN(Software Defined Networking; 소프트웨어 정의 네트워킹)이 가능한 장치를 구비하는 차량의 위치를 추적하는 시스템에 있어서, 차량의 위치의 추적 대상이 되는 특정 지역에 에지 크라우드를 적용하는 차량에 설치되는 SDN 제어장치(110, 120, 130)와, 상기 차량에서 발생하는 차량 속도, 위치 및 가속도를 포함하는 운행정보를 상기 SDN 제어장치로부터 전송받는 에지 제어기(Edge Controller; EC)를 포함하여 구성될 수 있다.Referring to FIGS. 1 to 3, the present invention provides a system for tracking the location of a vehicle including a device capable of Software Defined Networking (SDN) under an edge crowd. SDN control device (110, 120, 130) installed in a vehicle that applies the edge crowd to a specific area, and operation information including vehicle speed, position, and acceleration generated in the vehicle is transmitted from the SDN control device. It may be configured to include an edge controller (EC).
이 경우, 상기 에지 제어기(EC)는, 상기 차량의 SDN 제어장치에서 제공되는 상기 운행정보를 바탕으로, IMM(Interacting Multiple Model; 상호작용 다수모델 프로그램)부(210)에 의해 확률밀도함수를 계산하고 누적하여 차량의 예상 위치를 산출하는 확장 칼만필터(Extended Kalman Filter; EKF)모듈(200)을 포함하여 구성될 수 있다.In this case, the edge controller (EC) calculates the probability density function by the IMM (Interacting Multiple Model) unit 210 based on the operation information provided from the SDN control device of the vehicle. And an Extended Kalman Filter (EKF) module 200 that accumulates and calculates an expected position of the vehicle.
따라서, 본 발명이 구현되는 실시예는, 차량통신에 SDN 네트워킹 기술이 구현되며, 이를 통해 통신이 가능하도록 전제되어 있고, 하나의 SDN 제어장치가 전체 망을 제어할 수도 없기 때문에, 지역마다 에지 클라우드가 적용되면, 지역 내의 도로에 대한 정보 전송과 연산이 가능한 환경을 전제로 한다.Therefore, in the embodiment in which the present invention is implemented, the SDN networking technology is implemented in vehicle communication, and communication is possible through this, and because one SDN control device cannot control the entire network, the edge cloud for each region When is applied, an environment in which information transmission and calculation for roads in the area is possible is premised.
따라서, 차량 자체의 컴퓨팅 자원이 아니라, 에지 클라우드에 있는 컴퓨팅자원이 Kalman 필터를 이용하여 차량의 위치를 계속적으로 계산이 가능하다면, SDN 제어기가 훨씬 안정적인 통신 제어를 할 수 있다는 전제를 가정한다. Therefore, it is assumed that if the computing resource in the edge cloud, not the computing resource of the vehicle itself, can continuously calculate the position of the vehicle using the Kalman filter, the SDN controller can perform much more stable communication control.
차량 통신에서 가장 안정성이 떨어지는 부분은 차량의 이동성 때문에 차량 간의 통신 링크가 수시로 바뀌어야 하는 상황 때문인데, 본 발명에 따른 시스템에 의해, 차량의 위치가 안정적으로 예측이 된다면, 제어기가 무선망의 한계를 넘어서, 트래픽 유실이 일어나지 않도록 제어 가능하게 되는 것이다.The least stable part of vehicle communication is due to the situation in which the communication link between vehicles must be changed from time to time due to the mobility of the vehicle.If the position of the vehicle is stably predicted by the system according to the present invention, the controller can overcome the limitations of the wireless network. Beyond that, it becomes controllable so that no traffic loss occurs.
이러한 기능을 구현하기 위해, 도 2에 도시된 것과 같이, 본 발명의 에지 제어기(EC)는, 운행수단에서 제공되는 상기 운행정보를 바탕으로, IMM(Interacting Multiple Model; 상호작용 다수모델 프로그램)부(210)에 의해 확률밀도함수를 계산하고 누적하여 차량의 예상 위치를 산출하는 확장 칼만필터(Extended Kalman Filter; EKF)모듈(210)을 포함하며, 또한, 예상 동적정보에 대한 예상 모델을 제공하는 예측모델 제공부(220)를 포함하여 구성될 수 있도록 한다.In order to implement this function, as shown in FIG. 2, the edge controller (EC) of the present invention includes an Interacting Multiple Model (IMM) unit based on the driving information provided by the driving means. It includes an extended Kalman filter (EKF) module 210 that calculates and accumulates the probability density function by 210 to calculate the predicted position of the vehicle, and provides a predicted model for predicted dynamic information. It can be configured to include a prediction model providing unit 220.
특히, 예측모델 제공부에서는, 차량 움직임의 모든 가능한 상황을 고려하여, 다섯 가지 KF(칼만필터) 모델을 도출하여 제공될 수 있도록 한다.In particular, the prediction model providing unit derives and provides five KF (Kalman filter) models in consideration of all possible situations of vehicle movement.
이러한 모델들 각각은 차량이 발견될 수 있는 특정 시나리오 세트, 즉 일정한 저크(jerk) 모델, 일정 가속 모델, 일정 속도 모델, 고정 위치 모델 및 차량 터닝(turning) 모델에 적합하도록 설정한 것이다.Each of these models is set to fit a specific set of scenarios in which the vehicle can be found, i.e. a constant jerk model, a constant acceleration model, a constant speed model, a fixed position model, and a vehicle turning model.
상기 예측모델 제공부(220)에서 제공되는 예측모델은, 하기의 {식 1} 내지 {식 5}에 따라 총 5가지 모델로 제공될 수 있다. (차량 위치(Xv), 차량 속도(Vv) 및 차량 이동 방향에 있는 가장 가까운 교차로로부터의 거리(Dv))The prediction model provided by the prediction model providing unit 220 may be provided as a total of five models according to the following {Equation 1} to {Equation 5}. (Vehicle position (Xv), vehicle speed (Vv), and distance from the nearest intersection in the direction of vehicle movement (Dv))
{식 1: Constant location model (일정 위치 모델; CL)}{Equation 1: Constant location model (CL)}
Figure PCTKR2020014441-appb-I000001
Figure PCTKR2020014441-appb-I000001
(일정 위치모델(CL)은 차량이 움직이지 않거나 속도가 '0'인 시나리오를 설명한다.)(Constant position model CL describes a scenario where the vehicle does not move or the speed is '0'.)
{식 2: Constant velocity model (일정 속도 모델; CV)}{Equation 2: Constant velocity model (CV)}
Figure PCTKR2020014441-appb-I000002
Figure PCTKR2020014441-appb-I000002
(일정 속도 모델(CV)는 차량의 현재위치 Xvt와 차량 이동 방향에 있는 가장 가까운 교차로에서의 거리 DvIt를 가진 차량이 등록 Vvt로 이동할 때 차량의 상황을 나타낸다. ω는 처리 노이즈 공분산(process noise covariance)이며, 이는 상수이다.)(Constant speed model (CV) represents the situation of the vehicle when the vehicle with the current position Xv t of the vehicle and the distance DvI t at the nearest intersection in the vehicle movement direction moves to the registration Vvt. ω is the processing noise covariance (process). noise covariance), which is a constant.)
{식 3: Constant acceleration model (일정 가속 모델; CA)}{Equation 3: Constant acceleration model (CA)}
Figure PCTKR2020014441-appb-I000003
Figure PCTKR2020014441-appb-I000003
(일정 가속도 모델(CA)는 차량이 일정한 가속도(a)를 가지고 이동할 때 차량의 상황을 나타낸다. 본 수식에서 차량의 상태는 위치는 유동적이게 이동상태에 있는 것으로 간주되며, Δ t는 이전 기간을 나타내며, 따라서 (t - 1)의 변수는 이전 기간의 통계를 의미한다. ω는 처리 노이즈 공분산(process noise covariance)이며, 이는 상수이다.)(Constant acceleration model (CA) represents the situation of the vehicle when the vehicle moves with a constant acceleration (a). In this equation, the state of the vehicle is considered to be in a moving state with a flexible position, and Δ t is the previous period. And thus the variable of (t-1) means the statistics of the previous period, ω is the process noise covariance, which is a constant.)
{식 4: Constant Jerk model (일정 저크(jerk) 모델; CJ)}{Equation 4: Constant Jerk model (constant jerk model; CJ)}
Figure PCTKR2020014441-appb-I000004
Figure PCTKR2020014441-appb-I000004
(일정 저크 모델(CJ)는 차량이 일정한 가속도에서 일정 시간 동안 가속도 변화를 가지고 이동할 때의 상황을 나타낸 것이다.)(Constant jerk model (CJ) represents a situation when a vehicle moves at a constant acceleration with a change in acceleration for a certain period of time.)
{식 5: Constant vehicle turn model (차량 터닝(turning)모델; VT)}{Equation 5: Constant vehicle turn model (vehicle turning model; VT)}
Figure PCTKR2020014441-appb-I000005
Figure PCTKR2020014441-appb-I000005
(차량의 터닝 모델(VT)는 차량의 SDN 제어장치에게, 차량이 지속적으로 회전을 하거나, 정션(jungtion)/인터섹션(intersection) 및 차선번호(가장 오른쪽, 왼쪽 또는 중간)의 두가지 매개 변수를 사용하여, 동일한 도로 상에서 직진할 것임을 표현한다.)(Vehicle's Turning Model (VT) tells the vehicle's SDN control unit that the vehicle is continuously rotating, or two parameters: junction/intersection and lane number (rightmost, left or middle). To express that you will go straight on the same road.)
즉, 차량이 우측 가장 큰 차선에 있고, DvIt 값이 거의 '0'에 가까운 경우에는 차량은 우측으로 회전하게 될 것이다.That is, if the vehicle is in the largest lane on the right, and the DvIt value is nearly '0', the vehicle will turn to the right.
또는, 차량이 좌측 차선에 배치되어 있고, DvIt 값이 거의 '0'에 가까우면 차량은 좌측으로 주행하게 될 것이다. 그러나 중간 차선의 차량은 직선 경로를 따른다.Alternatively, if the vehicle is placed in the left lane and the DvIt value is close to '0', the vehicle will drive to the left. However, vehicles in the middle lane follow a straight path.
본 발명의 칼만필터는 피드백 접근 방식으로 작동하며, 먼저 시간 T에서 데이터를 처리하며, 차량 속도, 위치 및 가속도를 포함하는 GPS 측정 측면에서 차량의 SDN 제어장치로부터 피드백을 받는다. 상태 벡터는 각각 x와 y 성분으로 분해되는 이러한 파라미터를 사용하여 형성된다.The Kalman filter of the present invention operates with a feedback approach, first processes data at time T, and receives feedback from the vehicle's SDN controller in terms of GPS measurement including vehicle speed, position and acceleration. State vectors are formed using these parameters, which are decomposed into x and y components, respectively.
본 발명에서 상술한 모델에 대한 상태 벡터를 정의하기 위해 방정식 1과 같이 위성 위치 확인 시스템 (GPS)를 기반으로 차량 위치(Xv), 차량 속도(Vv) 및 차량 이동 방향에 있는 가장 가까운 교차로로부터의 거리(Dv) 세 가지 파라미터를 고려했다. In order to define the state vector for the above-described model in the present invention, based on the satellite positioning system (GPS) as shown in Equation 1, the vehicle position (Xv), the vehicle speed (Vv), and from the nearest intersection in the vehicle movement direction are Three parameters of distance (Dv) were considered.
{방정식 1}{Equation 1}
Figure PCTKR2020014441-appb-I000006
Figure PCTKR2020014441-appb-I000006
그런 다음 세 가지 매개변수가 각각 x와 y 성분으로 분해된다. 따라서 방정식의 모든 Xv에 대해 각각 Xxv와 Xyv로 표시된다.Then the three parameters are decomposed into x and y components, respectively. Thus, for every Xv in the equation, it is denoted as Xxv and Xyv, respectively.
위의 방정식에서 모든 파라미터는 x와 y의 두 가지 구성 요소, 즉 x와 y 좌표의 위치, 정상 및 접선 가속을 가지고 있다. 또한 KF를 이용한 차량 위치의 보정 및 예측 공식은 다음과 같다.In the above equation, every parameter has two components, x and y, i.e. the position of the x and y coordinates, and the normal and tangential acceleration. In addition, the formula for vehicle position correction and prediction using KF is as follows.
[차량 위치 보정 예측 공식][Vehicle position correction prediction formula]
Figure PCTKR2020014441-appb-I000007
Figure PCTKR2020014441-appb-I000007
H는 모수 모델의 Jacobian을 나타내고, P는 예측 오차 공분산이고, R은 모형의 소음 공분산이고, K는 Kalman 이득이다. x는 시간 k-1에서 차량의 상태 예측을 나타내고, k는 현재 시간을 나타내며, A는 현재 상태에 대한 Jacobian의 시스템 모델을 나타낸다.H is the Jacobian of the parametric model, P is the prediction error covariance, R is the noise covariance of the model, and K is the Kalman gain. x represents the prediction of the vehicle's condition at time k-1, k represents the current time, and A represents Jacobian's system model for the current state.
일반적으로, 차량은 자체에 네비게이션 지도와 같은 GIS 시스템을 가지고 있으므로, 구부러진 도로에서는 그러한 도로를 인지해서 위치 예측의 정확성을 줄일 수 있으나, 본 발명의 일 실시예에서는 직선도로만을 고려하여 수식을 제시하였다. Kalman 필터를 위해, 예측된 covariance P(공분산 P)는 다음과 같다. In general, since a vehicle has its own GIS system such as a navigation map, it is possible to reduce the accuracy of location prediction by recognizing such a road on a curved road, but in an embodiment of the present invention, an equation is presented in consideration of only a straight road. . For the Kalman filter, the predicted covariance P (covariance P) is
Figure PCTKR2020014441-appb-I000008
Figure PCTKR2020014441-appb-I000008
(이 경우, 차량 위치(Xv), 차량 속도(Vv) 및 차량 이동 방향에 있는 가장 가까운 교차로로부터의 거리(Dv) 이다. 행렬 ′P′는 추정 오차 공분산을 나타내며, 이후 ′R′(측정 노이즈)과 함께 사용된다. ′K′(칼만 이득)의 값을 추정하기 위한 공분산) 및 'H′(자코비아 행렬). 매트릭스 ′PP는 데이터 집합으로, 수직 수준의 모든 쌍 사이의 관찰 오류에 있는 연관성을 설명한다. 우리의 경우 제안된 모든 모델에 대한 오류 공분산은 필터를 자체로 매핑하여 추정한다.)(In this case, the vehicle position (Xv), the vehicle speed (Vv), and the distance from the nearest intersection in the vehicle movement direction (Dv). The matrix ′P′ represents the estimated error covariance, and then ′R′ (measured noise ) Are used together with'K' (covariance to estimate the value of Kalman gain) and'H' (Jacobia matrix). The matrix'PP is a data set, describing the association in the observation error between all pairs at the vertical level. In our case, the error covariance for all proposed models is estimated by mapping the filter itself.)
차량의 가능한 모든 시나리오들을 확보한 후, 확률 밀도 함수 (pdf)를 계산하고 차량의 미래 위치를 예측하기 위해 가장 가능성이 높은 모델을 선택하게 된다. 이는 Markov model(마르코프 모델)을 사용하여 각 모델에 대한 발생 확률을 누적하는 IMM 알고리즘에 의해 수행되고 최종 전이 매트릭은 모든 확률들로 정의되게 된다.After obtaining all possible scenarios of the vehicle, the probability density function (pdf) is calculated and the most probable model is selected to predict the future position of the vehicle. This is done by the IMM algorithm that accumulates the probability of occurrence for each model using the Markov model, and the final transition metric is defined as all probabilities.
상기 5가지 예측 모델(칼만 모델)을 통해, IMM부에서는 아래와 같은 피드백 프로세서를 통해 다음 지점에 대한 예측을 하도록 한다.Through the five prediction models (Kalman model), the IMM unit predicts the next point through the feedback processor as follows.
[피드백 프로세서][Feedback Processor]
Figure PCTKR2020014441-appb-I000009
Figure PCTKR2020014441-appb-I000009
이상의 과정을 본 발명의 시스템을 통해 다음과 같은 방식으로 구동되는 솔루션으로 제공할 수 있다.The above process can be provided as a solution driven in the following manner through the system of the present invention.
우선, 에지 크라우드 하에서, SDN(Software Defined Networking; 소프트웨어 정의 네트워킹)이 가능한 장치를 구비하는 차량의 위치를 추적하는 방법에 있어서, 차량의 SDN 장치를 통해 에지클라우드의 에지 제어기에 차량의 위치, 속도, 가속도를 포함하는 운행정보를 전송하는 1 단계가 수행될 수 있도록 한다.First, in an edge crowd, in a method of tracking the location of a vehicle equipped with a device capable of Software Defined Networking (SDN), the vehicle location, speed, and speed, to the edge controller of the edge cloud through the vehicle's SDN device, Step 1 of transmitting driving information including acceleration can be performed.
이 경우, 상기 에지 제어기 내의 확장 칼만필터(Extended Kalman Filter; EKF)모듈(200)에서, 상기 운행정보를 바탕으로, IMM(Interacting Multiple Model; 상호작용 다수모델 프로그램)부(210)에 의해 확률밀도함수를 계산하고 누적하여 차량의 예상 위치를 산출하는 2단계가 수행될 수 있다.In this case, in the extended Kalman filter (EKF) module 200 in the edge controller, the probability density by the IMM (Interacting Multiple Model; Interacting Multiple Model Program) unit 210 based on the operation information The second step of calculating and accumulating the function to calculate the expected position of the vehicle may be performed.
특히, 상기 2단계는, IMM(Interacting Multiple Model; 상호작용 다수모델 프로그램)부(210)에서, 차량의 움직임을 모델화한 예측모델에 대한 발생확률을 계산하고, 상기 계산된 확률을 적용하여 해당 모델을 통한 차량 위치 예측의 지배력을 식별하는 단계가 수행되도록 할 수 있다.In particular, the second step is, in the IMM (Interacting Multiple Model; interactive multiple model program) unit 210, calculates an occurrence probability for a predictive model modeled on the movement of the vehicle, and applies the calculated probability to the corresponding model. The step of identifying the dominance of vehicle position prediction through may be performed.
상기 IMM부(210)는, 상기 피드백 과정을 통해 지배적 모델(식 1~식 5에 따른 모델 중에서)을 식별하는 경우, 차량의 전체 주행에서 각 반복에 대한 확률을 계속 재계산하여 이전 반복에서 계산된 확률 값에 대해 새로운 확률 값을 가중하는 방식으로 수행하며, 이를 통해 산출된 정보를 기반으로, 하기의 식 7에 따른 상태 전환 매트릭스를 통해 각 모델의 확률을 계산하게 된다. IMM부(210)는, 이 과정에서 Markov(마르코프) 체인 모델을 사용해 확률 밀도 함수(pdf)를 계산한 후 각 모델에 대한 누적 확률을 계산하게 된다.When the IMM unit 210 identifies the dominant model (from the models according to Equations 1 to 5) through the feedback process, the probability for each iteration is continuously recalculated and calculated from the previous iteration. A new probability value is weighted with respect to the generated probability value, and the probability of each model is calculated through the state transition matrix according to Equation 7 below, based on the calculated information. In this process, the IMM unit 210 calculates a probability density function (pdf) using a Markov (Markov) chain model, and then calculates a cumulative probability for each model.
{식 7}{Equation 7}
Figure PCTKR2020014441-appb-I000010
Figure PCTKR2020014441-appb-I000010
(CL: 일정 위치모델, CV: 일정 속도모델, CA: 일정 가속도 모델, CJ: 일정 저크 모델, VT: 차량 터닝 모델)(CL: constant position model, CV: constant speed model, CA: constant acceleration model, CJ: constant jerk model, VT: vehicle turning model)
예를 들어, 현재 차량위치는 일정한 위치모델(CL)을 사용하여 추정한 다음, CL 모델을 향후 차량 위치를 찾기 위해 다시 적용하거나 다른 모델을 적용해야 할 확률을 계산한다.For example, the current vehicle position is estimated using a constant position model (CL), and then the CL model is re-applied to find the vehicle position in the future, or a probability of applying another model is calculated.
이를 위해 IMM부는 Markov(마르코프) 체인 모델을 사용해 확률 밀도 함수(pdf)를 계산한 후 확률을 계산한다. 차량 위치 예측을 위해 가능성이 가장 높은 모델을 선택하게 된다.To this end, the IMM unit calculates the probability density function (pdf) using the Markov chain model and then calculates the probability. The model with the highest probability is selected for vehicle position prediction.
도 3은 본 발명에 따른 시스템(도 1 및 도 2) 적용을 도시한 개념도이다.3 is a conceptual diagram showing the application of the system (FIGS. 1 and 2) according to the present invention.
도 3을 참조하여 본 발명의 작용상태를 정리하면 다음과 같다.The operational state of the present invention is summarized as follows with reference to FIG. 3.
특정 지역에 이동하는 차량의 소프트 정의 인터넷(SD-IoV)에서는 도로상의 차량들이 정보를 동적으로 전달하기 위해 셀룰러 네트워크를 탐색하고, RSU (Road Side Unit)와 차량 간 데이터 통신을 위해 RSU (Road Side Unit)를 탐색한다. In the Soft-Defined Internet (SD-IoV) of vehicles moving to a specific area, vehicles on the road search cellular networks to transmit information dynamically, and RSU (Road Side Unit) and RSU (Road Side Unit) to communicate data between vehicles. Unit).
이 경우, 본 발명에서의 확장 칼만 필터모듈은 에지 제어기(EC)에서 차량 예측에 사용된다. In this case, the extended Kalman filter module in the present invention is used for vehicle prediction in the edge controller (EC).
일반적으로, 칼만필터(KF)는 일련의 수학 방정식을 사용해 차량의 미래 상태를 예측하는 효율적인 재귀적 방법을 제공한다. 다중 모델 접근방식이 있는 칼만필터(KF)는 단일 모델이지만 복잡한 모델을 피한다. 각 KF 모델에 따라 시나리오를 하위 시나리오로 나누는 것은 복잡도가 높은 시나리오보다는 정확한 결과를 얻기 때문이다. 이러한 차량에 대한 시나리오는 무동력 차량, 일정한 가속력 차량, 일정한 속도를 가진 차량 및 가변 가속력 차량(본 발명에서 제안한 5가지 모델)이다. 본 발명에서의 확장 칼만필터 모듈의 경우, 5가지 모델을 통해 운행정보를 바탕으로, IMM(Interacting Multiple Model; 상호작용 다수모델 프로그램)부에 의해 확률밀도함수를 계산하고 누적하여 차량의 예상 위치를 산출하는 하게 된다.In general, the Kalman filter (KF) provides an efficient recursive method for predicting the future state of a vehicle using a series of mathematical equations. The Kalman filter (KF) with a multi-model approach is a single model, but avoids complex models. Scenarios are divided into sub-scenarios according to each KF model because more accurate results are obtained than scenarios with high complexity. Scenarios for such a vehicle are a non-powered vehicle, a constant acceleration vehicle, a vehicle with a constant speed, and a variable acceleration vehicle (five models proposed in the present invention). In the case of the extended Kalman filter module in the present invention, the predicted position of the vehicle is calculated by calculating and accumulating a probability density function by an IMM (Interacting Multiple Model) unit based on driving information through five models. It is done to calculate.
즉, 이러한 차량의 이동, 가속, 위치, 가변, 턴 등의 시나리오를 조합하여 완전한 일련의 방정식을 도출하여 시간(T)의 차량 위치를 예측할 수 있게 된다. 이 예측 프로세스는 에지 컨트롤러(EC)에 의해 수행된다. 차량의 미래 위치를 완전히 예측한 후 흐름 규칙을 각 RSU (Road Side Unit)에 설치하여 예측된 경로에서 데이터 패킷을 효율적으로 전달한다. RSU (Road Side Unit)와 인접 차량에 흐름 규칙을 설치하면 도 3에서와 같이 소스 차량이 SDN 제어장치로 경로 요청을 반복해서 보내지 않고 따라서 새로운 경로를 즉시 찾을 수 있다.That is, by combining the scenarios such as movement, acceleration, position, variable, and turn of the vehicle, a complete series of equations can be derived to predict the vehicle position in time (T). This prediction process is performed by the edge controller (EC). After fully predicting the future location of the vehicle, flow rules are installed in each RSU (Road Side Unit) to efficiently deliver data packets in the predicted path. When a flow rule is installed in the RSU (Road Side Unit) and adjacent vehicles, the source vehicle does not repeatedly send a route request to the SDN controller as shown in FIG. 3, and thus a new route can be immediately found.
즉, 본 발명은 차량의 위치를 추정하기 위해 차량의 소프트 정의 인터넷에 새로운 기법을 도입하여 차량이 다른 이웃 차량으로 새로운 도로 구간으로 진입할 때 새로운 경로를 미리 확보할 수 있도록 한다. 본 발명에서 제안된 5가지 위치 예측 모델은 직선 경로뿐만 아니라 무작위 및 곡선 경로에서도 차량 위치를 예측할 수 있도록 할 수 있다.That is, the present invention introduces a new technique to the soft-definition Internet of a vehicle in order to estimate the location of a vehicle, so that a new route can be secured in advance when a vehicle enters a new road section with another neighboring vehicle. The five position prediction models proposed in the present invention can predict the vehicle position not only on a straight path, but also on a random and curved path.
자율주행 차량에 대한 관심이 높아지면서, 그 근간이 되는 차량 통신은 필수적이다. 차량 통신 중에서 V2V, 즉 차량간 통신이 가장 안정성이 떨어지는 분야이기 때문에 이에 대한 보완이 필수적이다. As interest in autonomous vehicles increases, vehicle communication, the basis of which is essential, is essential. Among vehicle communications, V2V, that is, vehicle-to-vehicle communication, is the field with the lowest stability, so it is essential to supplement this.
LTE망을 통해 자율주행에 필요한 통신을 할 경우, 막대한 양의 데이터를 주고받아야 하는데, 이는 직접적인 통신방식인 V2I만을 고려한 것이기 때문에, V2V를 통해서 RSU(Road Side Unit)를 통한 통신이 필수 불가결하게 된다.When performing communication necessary for autonomous driving through the LTE network, a huge amount of data needs to be exchanged, and since this is only considering V2I, which is a direct communication method, communication through the RSU (Road Side Unit) through V2V becomes indispensable. .
이에, 본 발명은 이러한 차량간 통신의 안정화에 있어서 필수적인 차량의 위치를 예측할 있도록 하는 모델을 제공할 수 있으므로, 향후 SDN 제어기를 차량 통신의 직접적인 안정화 모델과 결합된다면, 아주 큰 경쟁력을 가지고 있다고 본다.Accordingly, the present invention can provide a model for predicting the position of a vehicle, which is essential for stabilizing such vehicle-to-vehicle communication, and thus, if the SDN controller is combined with a direct stabilization model for vehicle communication in the future, it is considered to have very great competitiveness.
본 발명에 따른 시스템 및 방법은, 차량의 위치를 예상해서, 차량통신의 안정화를 가져오고자 하는 것으로, 에지 클라우드에서 이뤄질 수 있다. The system and method according to the present invention are intended to bring about stabilization of vehicle communication by estimating the location of the vehicle, and can be performed in the edge cloud.
따라서, 기간망의 통신 인프라를 이용해서 해당 차량의 통신 안정화를 필요로 하는 ITS 센터는 물론이고, 통신망 사업자가 사용할 수 있으며, 차량 통신 서비스를 제공하는 업체에 적용할 수 있다.Therefore, it can be used by communication network operators as well as ITS centers that require communication stabilization of the vehicle by using the communication infrastructure of the backbone network, and can be applied to companies that provide vehicle communication services.
본 발명에서 제공하는 확장 칼만 필터 모듈을 통해 구현되는 각 모델을 통해 수행하는 차량의 위치 예측 구현 솔루션 기능은 프로그램화 하여 제공될 수 있도록 하며, 본 발명에서는 이러한 응용프로그램이 기록된 컴퓨터 판독이 가능한 기록매체를 컴퓨터 또는 이동통신단말기(예를 들면, 스마트폰, 태블릿 PC)를 이용하여 실행할 수 있다. 이때, 이러한 응용 프로그램은 컴퓨터의 하드디스크에 설치되거나, 혹은 CD-ROM 또는 DVD-ROM에 설치되거나, 혹은 USB 메모리에 설치되어 실행될 수 있다. 이외에도 다양한 재생장치에 설치되어 실행될 수 있다. The vehicle position prediction implementation solution function performed through each model implemented through the extended Kalman filter module provided by the present invention can be programmed and provided, and in the present invention, a computer-readable recording of such an application program is recorded. The medium can be executed using a computer or a mobile communication terminal (eg, a smartphone or a tablet PC). In this case, such an application program may be installed on a hard disk of a computer, installed on a CD-ROM or a DVD-ROM, or installed on a USB memory and executed. In addition, it can be installed and executed in various playback devices.
아울러, 본 발명의 시스템이 적용되는 통신망은, 유무선 통신이 가능한 망(network)으로서, 통신사에서 설치 운영하는 이동통신망(3G망, 4G망, 5G망, WiBro망, LTE망 포함), 인터넷망/PSTN(Public Switched Telephone Network)망을 포함할 수 있다.In addition, the communication network to which the system of the present invention is applied is a network capable of wired and wireless communication, and a mobile communication network installed and operated by a communication company (including 3G network, 4G network, 5G network, WiBro network, LTE network), Internet network/ It may include a public switched telephone network (PSTN) network.
본 발명에 적용되어 에지 제어기서 구현되는 칼만 필터 모듈의 구성 및 수행동작은 기능적인 블록 구성들 및 다양한 처리 단계들로 나타내어질 수 있다. 이러한 기능 블록들은 특정 기능들을 실행하는 다양한 개수의 하드웨어 또는/및 소프트웨어 구성들로 구현될 수 있다. 예를 들어, 본 발명은 하나 이상의 마이크로프로세서들의 제어 또는 다른 제어 장치들에 의해서 다양한 기능들을 실행할 수 있는, 메모리, 프로세싱, 로직(logic), 룩업 테이블(look-up table) 등과 같은 직접 회로 구성들을 채용할 수 있다.The configuration and execution operation of the Kalman filter module applied to the present invention and implemented in the edge controller may be represented by functional block configurations and various processing steps. These functional blocks may be implemented with various numbers of hardware or/and software configurations that perform specific functions. For example, the present invention provides integrated circuit configurations such as memory, processing, logic, and look-up tables, which can execute various functions by controlling one or more microprocessors or by other control devices. Can be adopted.
본 발명에의 구성 요소들이 소프트웨어 프로그래밍 또는 소프트웨어 요소들로 실행될 수 있는 것과 유사하게, 본 발명은 데이터 구조, 프로세스들, 루틴들 또는 다른 프로그래밍 구성들의 조합으로 구현되는 다양한 알고리즘을 포함하여, C, C++, 자바(Java), 어셈블러(assembler) 등과 같은 프로그래밍 또는 스크립팅 언어로 구현될 수 있다. 기능적인 측면들은 하나 이상의 프로세서들에서 실행되는 알고리즘으로 구현될 수 있다. 또한, 본 발명은 전자적인 환경 설정, 신호 처리, 및/또는 데이터 처리 등을 위하여 종래 기술을 채용할 수 있다. "매커니즘", "요소", "수단", "구성"과 같은 용어는 넓게 사용될 수 있으며, 기계적이고 물리적인 구성들로서 한정되는 것은 아니다. 상기 용어는 프로세서 등과 연계하여 소프트웨어의 일련의 처리들(routines)의 의미를 포함할 수 있다.Similar to how the elements of the present invention can be implemented with software programming or software elements, the present invention includes various algorithms implemented with a combination of data structures, processes, routines or other programming constructs, including C, C++. , Java, assembler, or the like may be implemented in a programming or scripting language. Functional aspects can be implemented with an algorithm running on one or more processors. In addition, the present invention may employ conventional techniques for electronic environment setting, signal processing, and/or data processing. Terms such as "mechanism", "element", "means", and "configuration" may be used broadly, and are not limited to mechanical and physical configurations. The term may include a meaning of a series of routines of software in connection with a processor or the like.
이상에서와 같이 본 발명의 기술적 사상은 바람직한 실시예에서 구체적으로 기술되었으나, 상기한 바람직한 실시예는 그 설명을 위한 것이며, 그 제한을 위한 것이 아니다. 이처럼 이 기술 분야의 통상의 전문가라면 본 발명의 기술 사상의 범위 내에서 본 발명의 실시예의 결합을 통해 다양한 실시예들이 가능함을 이해할 수 있을 것이다.As described above, the technical idea of the present invention has been described in detail in the preferred embodiment, but the preferred embodiment is for the purpose of explanation and not limitation. As such, it will be understood by those of ordinary skill in the art that various embodiments are possible through a combination of the embodiments of the present invention within the scope of the technical idea of the present invention.

Claims (14)

  1. 에지 크라우드 하에서, SDN(Software Defined Networking; 소프트웨어 정의 네트워킹)이 가능한 장치를 구비하는 차량의 위치를 추적하는 시스템에 있어서,In a system for tracking the location of a vehicle equipped with a device capable of Software Defined Networking (SDN) under an edge crowd,
    차량의 위치의 추적 대상이 되는 특정 지역에 에지 크라우드를 적용하는 차량에 설치되는 SDN 제어장치;An SDN control device installed in a vehicle applying an edge crowd to a specific area to be tracked of a vehicle location;
    상기 차량에서 발생하는 차량 속도, 위치 및 가속도를 포함하는 운행정보를 상기 SDN 제어장치로부터 전송받는 에지 제어기(Edge Controller);An edge controller that receives driving information including vehicle speed, position, and acceleration generated in the vehicle from the SDN control device;
    상기 에지 제어기는,The edge controller,
    상기 운행수단에서 제공되는 상기 운행정보를 바탕으로, IMM(Interacting Multiple Model; 상호작용 다수모델 프로그램)부에 의해 확률밀도함수를 계산하고 누적하여 차량의 예상 위치를 산출하는 확장 칼만필터(Extended Kalman Filter; EKF)모듈;Based on the driving information provided by the driving means, an extended Kalman filter that calculates and accumulates a probability density function by an Interacting Multiple Model (IMM) unit to calculate the expected position of the vehicle. ; EKF) module;
    를 포함하는,Containing,
    차량 소프트웨어 정의 네트워킹에서 확장 칼만필터를 이용하는 차량 궤적 예측시스템.Vehicle trajectory prediction system using extended Kalman filter in vehicle software-defined networking.
  2. 제1항에 있어서,The method of claim 1,
    상기 확장 칼만필터 모듈은,The extended Kalman filter module,
    차량의 예상 동적정보에 대한 예상 모델을 제공하는 예측모델 제공부;를 포함하며,Includes; a prediction model providing unit that provides a predicted model for predicted dynamic information of the vehicle,
    상기 예측모델 제공부에서 제공되는 예측모델은, 하기의 {식 1} 내지 {식 5}에 의해 결정되는,The prediction model provided by the prediction model providing unit is determined by the following {Equation 1} to {Equation 5},
    차량 소프트웨어 정의 네트워킹에서 확장 칼만필터를 이용하는 차량 궤적 예측시스템.Vehicle trajectory prediction system using extended Kalman filter in vehicle software-defined networking.
    {식 1: Constant location model (일정 위치 모델; CL)}{Equation 1: Constant location model (CL)}
    Figure PCTKR2020014441-appb-I000011
    Figure PCTKR2020014441-appb-I000011
    (일정 위치모델(CL)은 차량이 움직이지 않거나 속도가 '0'인 시나리오를 설명한다.)(Constant position model CL describes a scenario where the vehicle does not move or the speed is '0'.)
    {식 2: Constant velocity model (일정 속도 모델; CV)}{Equation 2: Constant velocity model (CV)}
    Figure PCTKR2020014441-appb-I000012
    Figure PCTKR2020014441-appb-I000012
    (일정 속도 모델(CV)는 차량의 현재위치 Xvt와 차량 이동 방향에 있는 가장 가까운 교차로에서의 거리 DvIt를 가진 차량이 등록 Vvt로 이동할 때 차량의 상황을 나타낸다. ω는 처리 노이즈 공분산(process noise covariance)이며, 이는 상수이다.)(Constant speed model (CV) represents the situation of the vehicle when the vehicle with the current position Xv t of the vehicle and the distance DvI t at the nearest intersection in the vehicle movement direction moves to the registration Vvt. ω is the processing noise covariance (process). noise covariance), which is a constant.)
    {식 3: Constant acceleration model (일정 가속 모델; CA)}{Equation 3: Constant acceleration model (CA)}
    Figure PCTKR2020014441-appb-I000013
    Figure PCTKR2020014441-appb-I000013
    (일정 가속도 모델(CA)는 차량이 일정한 가속도(a)를 가지고 이동할 때 차량의 상황을 나타낸다. 본 수식에서 차량의 상태는 위치는 유동적이게 이동상태에 있는 것으로 간주되며, Δ t는 이전 기간을 나타내며, 따라서 (t - 1)의 변수는 이전 기간의 통계를 의미한다. ω는 처리 노이즈 공분산(process noise covariance)이며, 이는 상수이다.)(Constant acceleration model (CA) represents the situation of the vehicle when the vehicle moves with a constant acceleration (a). In this equation, the state of the vehicle is considered to be in a moving state with a flexible position, and Δ t is the previous period. And thus the variable of (t-1) means the statistics of the previous period, ω is the process noise covariance, which is a constant.)
    {식 4: Constant Jerk model (일정 저크(jerk) 모델; CJ)}{Equation 4: Constant Jerk model (constant jerk model; CJ)}
    Figure PCTKR2020014441-appb-I000014
    Figure PCTKR2020014441-appb-I000014
    (일정 저크 모델(CJ)는 차량이 일정한 가속도에서 일정 시간 동안 가속도 변화를 가지고 이동할 때의 상황을 나타낸 것이다.)(Constant jerk model (CJ) represents a situation when a vehicle moves at a constant acceleration with a change in acceleration for a certain period of time.)
    {식 5: Constant vehicle turn model (차량 터닝(turning) 모델; VT)}{Equation 5: Constant vehicle turn model (Vehicle turning model; VT)}
    Figure PCTKR2020014441-appb-I000015
    Figure PCTKR2020014441-appb-I000015
    (차량의 터닝 모델(VT)는 차량의 SDN 제어장치에게, 차량이 지속적으로 회전을 하거나, 정션(jungtion)/인터섹션(intersection) 및 차선번호(가장 오른쪽, 왼쪽 또는 중간)의 두가지 매개 변수를 사용하여, 동일한 도로 상에서 직진할 것임을 표현한다.)(Vehicle's turning model (VT) tells the vehicle's SDN control unit that the vehicle is continuously rotating, or two parameters: junction/intersection and lane number (rightmost, left or middle). To express that you will go straight on the same road.)
  3. 제2항에 있어서,The method of claim 2,
    상기 확장 칼만필터 모듈의 상기 IMM부는,The IMM part of the extended Kalman filter module,
    상기 예측모델 제공부에서 제공하는 5가지 모델을 이용하여 하기의 피드백 과정을 반복하며,The following feedback process is repeated using the five models provided by the prediction model providing unit,
    각 개별 모델에 대한 발생 확률을 계산하고, 상기 계산된 확률을 사용하여 어느 모델이 차량의 위치 예측에 지배적일지 식별하는,Calculating the probability of occurrence for each individual model, and using the calculated probability to identify which model will dominate the vehicle's position prediction,
    차량 소프트웨어 정의 네트워킹에서 확장 칼만필터를 이용하는 차량 궤적 예측시스템.Vehicle trajectory prediction system using extended Kalman filter in vehicle software defined networking.
  4. 제3항에 있어서,The method of claim 3,
    상기 피드백 과정은,The feedback process,
    하기의 {식 6-1}을 통한 예측과정과 {식 6-2}를 통한 업데이트 과정을 수행하며, 예측오차를 수정하는,Performing the prediction process through the following {Equation 6-1} and the update process through {Equation 6-2}, and correcting the prediction error,
    차량 소프트웨어 정의 네트워킹에서 확장 칼만필터를 이용하는 차량 궤적 예측시스템.Vehicle trajectory prediction system using extended Kalman filter in vehicle software defined networking.
    {식 6-1}{Equation 6-1}
    Figure PCTKR2020014441-appb-I000016
    Figure PCTKR2020014441-appb-I000016
    {식 6-2}{Equation 6-2}
    Figure PCTKR2020014441-appb-I000017
    Figure PCTKR2020014441-appb-I000017
    (H는 모수 모델의 Jacobian 행렬을 나타내고, P는 예측 오차 공분산이고, R은 모형의 측정 노이즈 공분산이고, K는 Kalman 이득이다. x는 시간 t-1에서 차량의 상태 예측을 나타내고, k는 현재 시간을 나타내며, A는 현재 상태에 대한 Jacobian의 시스템 모델을 나타낸다.) ( H represents the Jacobian matrix of the parametric model, P is the prediction error covariance, R is the measurement noise covariance of the model, K is the Kalman gain. x represents the prediction of the vehicle's condition at time t-1, and k is the current Represents time, and A represents Jacobian's system model for the current state. )
  5. 제4항에 있어서,The method of claim 4,
    상기 IMM부는,The IMM unit,
    상기 피드백 과정을 통해 지배적 모델을 식별하는 경우,In the case of identifying the dominant model through the feedback process,
    차량의 전체 주행에서 각 반복에 대한 확률을 계속 재계산하여 이전 반복에서 계산된 확률 값에 대해 새로운 확률 값을 가중하는 방식으로 수행하며,It is performed by continuously recalculating the probability for each iteration over the entire driving of the vehicle and weighting a new probability value to the probability value calculated in the previous iteration,
    이를 통해 산출된 정보를 기반으로, 하기의 식 7에 따른 상태 전환 매트릭스를 통해 각 모델의 확률을 계산하는,Based on the information calculated through this, the probability of each model is calculated through the state transition matrix according to Equation 7 below,
    차량 소프트웨어 정의 네트워킹에서 확장 칼만필터를 이용하는 차량 궤적 예측시스템.Vehicle trajectory prediction system using extended Kalman filter in vehicle software defined networking.
    {식 7}{Equation 7}
    Figure PCTKR2020014441-appb-I000018
    Figure PCTKR2020014441-appb-I000018
    (CL: 일정 위치모델, CV: 일정 속도모델, CA: 일정 가속도 모델, CJ: 일정 저크 모델, VT: 차량 터닝 모델)(CL: constant position model, CV: constant speed model, CA: constant acceleration model, CJ: constant jerk model, VT: vehicle turning model)
  6. 제5항에 있어서,The method of claim 5,
    상기 IMM부는,The IMM unit,
    Markov 체인 모델을 사용해 확률 밀도 함수(pdf)를 계산한 후 각 모델에 대한 누적 확률을 계산하는,After calculating the probability density function (pdf) using the Markov chain model, we compute the cumulative probability for each model,
    차량 소프트웨어 정의 네트워킹에서 확장 칼만필터를 이용하는 차량 궤적 예측시스템.Vehicle trajectory prediction system using extended Kalman filter in vehicle software defined networking.
  7. 청구항 1에 따른 시스템을 적용하여, 에지 크라우드 하에서, SDN(Software Defined Networking; 소프트웨어 정의 네트워킹)이 가능한 장치를 구비하는 차량의 위치를 추적하는 방법에 있어서,In the method for tracking the location of a vehicle equipped with a device capable of Software Defined Networking (SDN) under an edge crowd by applying the system according to claim 1,
    차량의 SDN 장치를 통해 에지 클라우드의 에지 제어기에 차량의 위치, 속도, 가속도를 포함하는 운행정보를 전송하는 1 단계;1 step of transmitting driving information including the position, speed, and acceleration of the vehicle to the edge controller of the edge cloud through the SDN device of the vehicle;
    상기 에지 제어기 내의 확장 칼만필터(Extended Kalman Filter; EKF)모듈에서, 상기 운행정보를 바탕으로, IMM(Interacting Multiple Model; 상호작용 다수모델 프로그램)부에 의해 확률밀도함수를 계산하고 누적하여 차량의 예상 위치를 산출하는 2단계; 를 포함하며,In the Extended Kalman Filter (EKF) module in the edge controller, the probability density function is calculated and accumulated by an Interacting Multiple Model (IMM) unit based on the driving information to predict the vehicle. A second step of calculating a location; Including,
    상기 2단계는,The second step,
    IMM(Interacting Multiple Model; 상호작용 다수모델 프로그램)부에서,In the IMM (Interacting Multiple Model; Interacting Multiple Model Program),
    차량의 움직임을 모델화한 예측모델에 대한 발생확률을 계산하고, 상기 계산된 확률을 적용하여 해당 모델을 통한 차량 위치 예측의 지배력을 식별하는 단계인,A step of calculating the probability of occurrence of a predictive model modeled on the movement of a vehicle, and identifying the dominance of vehicle position prediction through the corresponding model by applying the calculated probability,
    차량 소프트웨어 정의 네트워킹에서 확장 칼만필터를 이용하는 차량 궤적 예측 방법.Vehicle trajectory prediction method using extended Kalman filter in vehicle software-defined networking.
  8. 제7항에 있어서,The method of claim 7,
    상기 예측모델은,The prediction model,
    하기 {식 1}에 따른 일정 위치모델(Constant location model; CL)을 포함하는,Including a constant location model (Constant location model; CL) according to the following {Equation 1},
    차량 소프트웨어 정의 네트워킹에서 확장 칼만필터를 이용하는 차량 궤적 예측 방법.Vehicle trajectory prediction method using extended Kalman filter in vehicle software-defined networking.
    {식 1}: Constant location model (일정 위치 모델; CL){Equation 1}: Constant location model
    Figure PCTKR2020014441-appb-I000019
    Figure PCTKR2020014441-appb-I000019
    (일정 위치모델(CL)은 차량이 움직이지 않거나 속도가 '0'인 시나리오를 설명한다.)(Constant position model CL describes a scenario where the vehicle does not move or the speed is '0'.)
  9. 제8항에 있어서,The method of claim 8,
    상기 예측모델은,The prediction model,
    하기 {식 2}에 따른 일정 속도 모델(Constant velocity model; CV)을 포함하는,Including a constant velocity model (Constant velocity model; CV) according to the following {Equation 2},
    차량 소프트웨어 정의 네트워킹에서 확장 칼만필터를 이용하는 차량 궤적 예측 방법.Vehicle trajectory prediction method using extended Kalman filter in vehicle software-defined networking.
    {식 2: Constant velocity model (일정 속도 모델; CV)}{Equation 2: Constant velocity model (CV)}
    Figure PCTKR2020014441-appb-I000020
    Figure PCTKR2020014441-appb-I000020
    (일정 속도 모델(CV)는 차량의 현재위치 Xvt와 차량 이동 방향에 있는 가장 가까운 교차로에서의 거리 DvIt를 가진 차량이 등록 Vvt로 이동할 때 차량의 상황을 나타낸다. ω는 처리 노이즈 공분산(process noise covariance)이며, 이는 상수이다.)(Constant speed model (CV) represents the situation of the vehicle when the vehicle with the current position Xv t of the vehicle and the distance DvI t at the nearest intersection in the vehicle movement direction moves to the registration Vvt. ω is the processing noise covariance (process). noise covariance), which is a constant.)
  10. 제9항에 있어서,The method of claim 9,
    상기 예측모델은,The prediction model,
    하기 {식 3}에 따른 일정 가속 모델(Constant acceleration model; CA)을 포함하는,Including a constant acceleration model (Constant acceleration model; CA) according to the following {Equation 3},
    차량 소프트웨어 정의 네트워킹에서 확장 칼만필터를 이용하는 차량 궤적 예측 방법.Vehicle trajectory prediction method using extended Kalman filter in vehicle software-defined networking.
    {식 3: Constant acceleration model (일정 가속 모델; CA)}{Equation 3: Constant acceleration model (CA)}
    Figure PCTKR2020014441-appb-I000021
    Figure PCTKR2020014441-appb-I000021
    (일정 가속도 모델(CA)는 차량이 일정한 가속도(a)를 가지고 이동할 때 차량의 상황을 나타낸다. 본 수식에서 차량의 상태는 위치는 유동적이게 이동상태에 있는 것으로 간주되며, Δ t는 이전 기간을 나타내며, 따라서 (t - 1)의 변수는 이전 기간의 통계를 의미한다. ω는 처리 노이즈 공분산(process noise covariance)이며, 이는 상수이다.)(Constant acceleration model (CA) represents the situation of the vehicle when the vehicle moves with a constant acceleration (a). In this equation, the state of the vehicle is considered to be in a moving state with a flexible position, and Δ t is the previous period. And thus the variable of (t-1) means the statistics of the previous period, ω is the process noise covariance, which is a constant.)
  11. 제10항에 있어서,The method of claim 10,
    상기 예측모델은,The prediction model,
    하기 {식 4}에 따른 일정 저크(jerk) 모델(Constant Jerk model; CJ)을 포함하는,Including a constant jerk model (Constant Jerk model; CJ) according to the following {Equation 4},
    차량 소프트웨어 정의 네트워킹에서 확장 칼만필터를 이용하는 차량 궤적 예측 방법.Vehicle trajectory prediction method using extended Kalman filter in vehicle software-defined networking.
    {식 4: Constant Jerk model (일정 저크(jerk) 모델; CJ)}{Equation 4: Constant Jerk model (constant jerk model; CJ)}
    Figure PCTKR2020014441-appb-I000022
    Figure PCTKR2020014441-appb-I000022
    (일정 저크 모델(CJ)는 차량이 일정한 가속도에서 일정 시간 동안 가속도 변화를 가지고 이동할 때의 상황을 나타낸 것이다.)(Constant jerk model (CJ) represents a situation when a vehicle moves at a constant acceleration with a change in acceleration for a certain period of time.)
  12. 제11항에 있어서The method of claim 11
    상기 예측모델은,The prediction model,
    하기 {식 5}에 따른 차량 터닝(turning) 모델(Constant vehicle turn model; VT)을 포함하는,Including a vehicle turning model (Constant vehicle turn model; VT) according to the following {Equation 5},
    차량 소프트웨어 정의 네트워킹에서 확장 칼만필터를 이용하는 차량 궤적 예측 방법.Vehicle trajectory prediction method using extended Kalman filter in vehicle software-defined networking.
    {식 5: Constant vehicle turn model (차량 터닝(turning) 모델; VT)}{Equation 5: Constant vehicle turn model (Vehicle turning model; VT)}
    Figure PCTKR2020014441-appb-I000023
    Figure PCTKR2020014441-appb-I000023
    (차량의 터닝 모델(VT)는 차량의 SDN 제어장치에게, 차량이 지속적으로 회전을 하거나, 정션(jungtion)/인터섹션(intersection) 및 차선번호(가장 오른쪽, 왼쪽 또는 중간)의 두가지 매개 변수를 사용하여, 동일한 도로 상에서 직진할 것임을 표현한다.)(Vehicle's Turning Model (VT) tells the vehicle's SDN control unit that the vehicle is continuously rotating, or two parameters: junction/intersection and lane number (rightmost, left or middle). To express that you will go straight on the same road.)
  13. 제12항에 있어서,The method of claim 12,
    상기 2단계는,The second step,
    모델을 이용하여 하기의 피드백 과정을 반복하며, 각 개별 모델에 대한 발생 확률을 계산하고, 상기 계산된 확률을 사용하여 어느 모델이 차량의 위치 예측에 지배적일지 식별하되,Using the model, the following feedback process is repeated, the probability of occurrence for each individual model is calculated, and the calculated probability is used to identify which model will dominate the vehicle position prediction,
    차량의 전체 주행에서 각 반복에 대한 확률을 계속 재계산하여 이전 반복에서 계산된 확률 값에 대해 새로운 확률 값을 가중하는 방식으로 수행하며,It is performed by continuously recalculating the probability for each iteration over the entire driving of the vehicle and weighting a new probability value to the probability value calculated in the previous iteration,
    이를 통해 산출된 정보를 기반으로, 하기의 {식 7}에 따른 상태 전환 매트릭스를 통해 각 모델의 확률을 계산하는,Based on the information calculated through this, the probability of each model is calculated through the state transition matrix according to the following {Equation 7},
    차량 소프트웨어 정의 네트워킹에서 확장 칼만필터를 이용하는 차량 궤적 예측 방법.Vehicle trajectory prediction method using extended Kalman filter in vehicle software-defined networking.
    {식 7}{Equation 7}
    Figure PCTKR2020014441-appb-I000024
    Figure PCTKR2020014441-appb-I000024
    (CL: 일정 위치모델, CV: 일정 속도모델, CA: 일정 가속도 모델, CJ: 일정 저크 모델, VT: 차량 터닝 모델)(CL: constant position model, CV: constant speed model, CA: constant acceleration model, CJ: constant jerk model, VT: vehicle turning model)
  14. 청구항 13에 의한 차량 소프트웨어 정의 네트워킹에서 확장 칼만필터를 이용하는 차량 궤적 예측 방법을 수행하는 프로그램이 기록된 컴퓨터 판독이 가능한 기록매체. A computer-readable recording medium in which a program for performing a vehicle trajectory prediction method using an extended Kalman filter in vehicle software defined networking according to claim 13 is recorded.
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