Patent Publication Number: US-2019197893-A1

Title: System and Method for Translating Roadside Device Position Data According to Differential Position Data

Description:
FIELD 
     The present disclosure relates to systems and methods for translating roadside device position data according to differential position data and, in particular, to systems and methods for translating roadside device position data at intersections to differential position data. 
     BACKGROUND 
     The information provided in this section is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure. 
     Many devices, including vehicles, include navigation systems that use satellite-transmitted data to determine their latitude, longitude, and altitude. For example, in the United States, the Global Positioning System (GPS) is one example of these types of satellite navigation systems that collectively known as Global Navigation Satellite Systems (GNSS). These devices can use the location data for navigation purposes, determining its current position, and the like. 
     SUMMARY 
     In an example, a roadside device is disclosed. In one or more implementations, the roadside device includes a deviation determination module that is configured to determine a difference between a determined current position of the roadside device and a predefined position of the roadside device. The roadside device also includes a modification module that is configured to modify geometry data representing an intersection environment based upon the difference, and a vehicle-to-everything (V2X) communication module that is configured to broadcast the modified geometry data within and/or around the intersection environment. 
     In another example, a method is disclosed. In an example implementation, the method includes determining a difference between a determined current position of the roadside device and a predefined position of a roadside device and modifying geometry data representing an intersection environment based upon the difference. The method also includes broadcasting the modified geometry data within and/or around the intersection environment. 
     In another example, a system is disclosed. In an example implementation, the system includes a roadside device configured to be positioned proximate to an intersection environment. The roadside device includes a deviation determination module that is configured to determine a difference between a determined current position of the roadside device and a predefined position of the roadside device, a modification module that is configured to modify geometry data representing the intersection environment based upon the difference. The roadside device also includes a vehicle-to-everything (V2X) communication module that is configured to broadcast the modified geometry data within and/or around the intersection environment. The modified geometry data is configured to be received at a vehicle-to-everything (V2X) communication module of one or more vehicles. 
     Further areas of applicability of the present disclosure will become apparent from the detailed description, the claims and the drawings. The detailed description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the disclosure. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present disclosure will become more fully understood from the detailed description and the accompanying drawings, wherein: 
         FIG. 1A  illustrates an example signalized intersection environment according to an example implementation of the present disclosure; 
         FIGS. 1B and 1C  illustrate an example non-signalized intersection environment according to an example implementation of the present disclosure; 
         FIG. 2  illustrates an example block diagram of a roadside device according to an example implementation of the present disclosure; 
         FIG. 3  illustrates an example block diagram of a vehicle according to an example implementation of the present disclosure; and 
         FIGS. 4 and 5  illustrate example flow diagrams of methods according to example implementations of the present disclosure. 
     
    
    
     In the drawings, reference numbers may be reused to identify similar and/or identical elements. 
     DETAILED DESCRIPTION 
     Vehicles have increasingly begun to employ vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) communications, collectively known as V2X, for communication purposes. For example, V2X communications include one or more communication networks in which vehicles and roadside devices are the communicating nodes that provide one another with information, such as safety warnings and traffic information. V2X communications allow vehicles to communicate with other vehicles, infrastructure, and/or pedestrians, using wireless communications technologies, such as, but not limited to, Dedicated Short Range Communications (DSRC). 
     Intelligent transportation systems (ITS) can use V2X services within and/or around intersection environments, such as signalized intersection environments. For example, the V2X services may use survey level map representations of the intersections to allow vehicles to locate themselves with respect to the different approach lanes. As a vehicle approaches the intersections, traffic control systems signals broadcast signals, such as Signal Phase and Timing (SPaT) messages, to provide traffic signal information to approaching vehicles. However, some intersections include multiple turning lanes. Thus, the traffic signals broadcast different SPaT message elements (e.g., signals) pertaining to each approach lane. 
     In order to distinguish among the SPaT message elements, the vehicle determines its location within the signalized intersection. The vehicle then compares the determined location with the data representing the survey level map representation to determine the lane in which the vehicle is traveling. Based upon the determined approach lane, the vehicle can determine the SPaT message element corresponding to the approach lane. 
     However, certain physical phenomenon, such as atmospheric conditions (i.e., atmospheric scintillation, etc.), can modify the GNSS accuracy of the roadside device and/or the vehicle. Thus, the roadside device broadcasts both the data representing the signalized intersection and Radio Technical Commission for Maritime Services (RTCM) correction signals to improve geospatial location accuracy. Additionally, the GNSS receiver of the vehicle must be capable of receiving the RTCM signals and processing the RTCM signals accordingly to improve the determined location of the vehicle based upon the vehicle&#39;s trajectory and the data representing the signalized intersection. 
     In some intersection environments, traffic signs are used to control traffic flow. For example, intersections can include stop signs notifying drivers to stop prior to proceeding through the intersection. These intersection environments may include marked pedestrian crossings signifying an area for pedestrians to cross the road. The pedestrian crossings can include stop bars (e.g., stop lines) indicating where motorists are to stop. Roadside devices can be used to broadcast data indicative of its position to allow a vehicle control system to determine the vehicle position with respect to the stop lines. However, as described above, the atmospheric conditions can modify the GNSS accuracy of the roadside device and/or the vehicle. 
     Accordingly, a roadside device that broadcasts modified data representing geometrical parameters of an intersection environment is disclosed. In one or more implementations, the roadside device includes a deviation determination module that is configured to determine a difference between a determined current position of the roadside device and a predefined position of the roadside device. The roadside device also includes a modification module that is configured to modify geometry data representing an intersection environment based upon the difference and a vehicle-to-everything (V2X) communication module that is configured to broadcast the modified geometry data within and/or around the signalized intersection. In using the roadside device of the present disclosure, the GNSS receiver of the vehicle does not have to be capable of receiving and/or processing the RTCM signals. 
       FIGS. 1A through 1C  illustrate example environments  100  that include a roadside device  102  that can modify geometry data, or MAP data, and broadcasts the modified geometry data. The roadside device  102  may include one or more stationary roadside devices that broadcast data representing geometry data. The geometry data can represent surveyed data, including latitude, longitude, and/or altitude parameters representing a signalized intersection environment. One or more vehicles  104  proximate to an intersection  106  receive the modified geometry data. In the example environment shown in  FIG. 1A , the intersection  106  includes a signalized intersection that includes one or more traffic signals  107 . In the example environment shown in  FIGS. 1B and 1C , the intersection  106  includes an intersection including one or more traffic signs  109  and stop lines  111 . 
       FIG. 2  illustrates an example block diagram of the roadside device  102  that communicates with a vehicle  104 . The roadside device  102  includes a position determining module  108 , a V2X communication module  110 , and a control module  112 . The control module  112  includes a memory  114 , a deviation determination module  116 , and a modification module  118 . Referring to  FIG. 3 , the vehicle  104  can include a position determining module  120 , a V2X communication module  122 , a vehicle control module  124 , vehicle systems  126 , and a display  128 . 
     In one or more implementations, the vehicle systems  126  can include a powertrain system, a steering system, and/or a braking system. For example, the vehicle systems  126  include the systems and/or components that operate the vehicle  104 . It is understood that the vehicle systems  126  may include any number of additional vehicle systems that can operate the vehicle. It is understood that the vehicle systems  126  used herein can be used within an autonomous vehicle. 
     The roadside device  102  can represent a communication node that enables vehicle-to-everything (V2X) communication. In one example, the roadside device  102  is positioned within an intersection  106 , such as a signalized intersection (see  FIG. 1A ) or a non-signalized intersection (see  FIGS. 1B and 1C ), environment that broadcasts information to the vehicle  104 . For instance, the information provided by the roadside device  102  includes geometry data, such as position coordinates corresponding to one or more portions of the roadway or landmarks within the intersection  106 . The position coordinates can be represented by latitude, longitude, altitude parameters, and/or any other similar location description data related to three-dimensional spaces. 
     The roadside device  102  communicates with vehicles  104  via a communication network  129 . The communication network  129  may comprise a variety of different types of networks and connections that are contemplated, including, but not limited to: the Internet; an intranet; a satellite network; a cellular network; a mobile data network; wired and/or wireless connections; and so forth. Examples of wireless networks include, but are not limited to: networks configured for communications according to: one or more standard of the Institute of Electrical and Electronics Engineers (IEEE), such as 802.11 or 802.16 (Wi-Max) standards; Wi-Fi standards promulgated by the Wi-Fi Alliance; Bluetooth standards promulgated by the Bluetooth Special Interest Group; Dedicated Short Range Communications (DSRC); Cellular/LTE/5G; and so on. 
     The position determining modules  108 ,  120  generate respective GNSS signals identifying a location of the roadside device  102  and the vehicle  104 , respectively. In various implementations, the position determining module  108 ,  120  each include a GNSS transceiver for communicating with GNSS satellites. 
     Referring to  FIG. 2 , the roadside device  102  communicates with GNSS communication systems, such as GNSS satellites, via the position determining module  108  to determine a current position (i.e., a current positional reading) of the roadside device  102 . The position determining module  108  determines the current position of the roadside device  102  based upon the GNSS signals and provides a signal indicative of the current position to the deviation determination module  116 . 
     The deviation determination module  116  determines whether the current position (i.e., current positional reading) matches a predefined position of the roadside device  102 . The predefined position may represent a surveyed position of the roadside device  102  (i.e., a surveyed position corresponding to the position determining module  108 ). The predefined position can be stored in the memory  114  and accessed by the deviation determination module  116 . In an implementation, the deviation determination module  116  compares the current position with the predefined position to determine a difference between current position and the predefined position. For example, the difference includes a differential vector representative (e.g., a differential vector reference) of the change in latitude, the change in longitude, and/or the change in altitude between the predefined position and the current position. In one example, the current positional reading may indicate that the current coordinates of the roadside device  102  are North and West of the predefined position, as referenced by the roadside device  102 - 1 . 
     In an implementation, the deviation determination module  116  provides a difference signal indicative of the difference (i.e., the differential vector) between the current position and the predefined position to the modification module  118 . The modification module  118  modifies the geometry data according to the determined difference between the current position and the predefined position. The geometry data represents the surveyed intersection  106  including the roadside device  102  at the predefined position. For example, the modification module  118  accesses the geometry data from the memory  114  and modifies the geometry data based upon the determined difference. 
     In an implementation, the geometry data is modified (i.e., translated, etc.) such that the coordinates of the geometry data are modified according to the differential vector. For example, each latitude coordinate is modified based upon the difference in latitude coordinates of the current position and the predefined position; each longitude coordinate is modified based upon the difference in longitude coordinates of the current position and the predefined position; and each altitude coordinate is modified based upon the difference in altitude coordinates of the current position and the predefined position. Thus, the modified coordinates of the modified intersection data correspond to the current position of the roadside device  102 , and the surveyed coordinates of the non-modified intersection data correspond to the predefined position of the roadside device  102 . The modification module  118  provides the modified intersection data to the V2X communication module  110 . 
     The V2X communication module  110  broadcasts the modified geometry data via the communication network  129 . Vehicles  104  within the intersection  106  receive the broadcasted modified geometry data, and the vehicles  104  can use the modified geometry data to localize to a given single lane approach and/or the stop lines  111 . 
     In non-signalized intersection environments (see  FIGS. 1B and 1C ), the roadside device  102  broadcasts modified geometry data. Vehicles  104  can use the modified data to determine proximity of the vehicle  104  with respect to traffic markers, such as stop lines  111 . In some implementations, the roadside device  102  can broadcast modified geometry data relating to multiple intersections  106  within the intersection environment. For example, with respect to  FIG. 1C , the roadside device  102  can broadcast modified geometry data pertaining to a first intersection  106 - 1  and a second intersection  106 - 2 . Vehicles  104  proximate to the second intersection  106 - 2  can use the modified geometry data broadcast from the roadside device  102  to determine proximity of the vehicle to traffic markers within the second intersection  106 - 2 . In this implementation, the roadside device  102  is located proximate to the first intersection  106 - 1  and distal to the second intersection  106 - 2 . 
     Referring to  FIG. 3 , the V2X communication module  122  receives the modified geometry data and provides this data to the vehicle control module  124 . The position determining module  120  communicates with the GNSS communication system to determine a current position (i.e., current positional reading) of the vehicle  104  and is provided to the vehicle control module  124 . The vehicle control module  124  determines the lane approach according to the geometry data and the current positional reading of the vehicle  104 . 
     The V2X communication module  122  receives signal phase and timing (SPaT) signals transmitted by the traffic signal  107 . For example, the traffic signal  107  includes a communication module  130  that receives SPaT signals from a traffic signal  107  controller and broadcasts the SPaT signals to vehicles approaching the signalized intersection  106 . The communication module  130  can transmit the SPaT signals via the communication network  129 . Based upon the determined lane approach, the vehicle control module  124  can determine the SPaT signal corresponding to the determined lane approach provided by a traffic signal  107 . 
     Based upon the determined SPaT signal, the vehicle control module  124  can operate one or more aspects of the vehicle  104 . For example, the vehicle control module  124  can generate and transmit a control signal to one or more vehicle systems  126  to operate the vehicle  104  accordingly. For instance, the control signal may actuate the braking system causing the vehicle  104  to brake, actuate the steering system causing the vehicle  104  to turn, and/or actuate the powertrain system to cause the vehicle  104  to accelerate. However, it is understood that the any number of control signals to operate various vehicle systems  126  can be generated to cause the vehicle  104  to operate accordingly. 
     The vehicle control module  124  can also generate a display control signal to cause the display  128  to display information pertaining to the intersection  106 . In one example, the vehicle control module  124  generates the display control signal to display a warning at the display  128 . In another example, the vehicle control module  124  generates the display control signal to display traffic signal  107  information. The traffic signal  107  information may include timing information of how long the current operational lane traffic signal is going to maintain its current signal state, timing information indicating a time length that the next state of operational lane traffic signal will maintain that state, and the like. 
       FIG. 4  illustrates an example method  400  for modifying geometry data in accordance with an example implementation of the present disclosure. The method begins at  402 . At  404 , the predefined position of the roadside device  102  is retrieved. At  406 , deviation determination module  116  receives the determined current position of the roadside device  102 . At  408 , the deviation determination module  116  calculates the difference between the current position and the predefined position of the roadside device  102 . 
     At  410 , the modification module  118  accesses the geometry data from the memory  114 . At  412 , the modification module  118  modifies the geometry data based upon the difference. At  414 , the V2X communication module  110  broadcasts the modified geometry data within the signalized intersection environment  100 . At  416 , the method ends. 
       FIG. 5  illustrates an example method  500  for receiving the modified geometry data at a vehicle  104  within a signalized intersection environment. At  502 , the method starts. At  504 , the V2X communication module  122  receives the modified geometry data broadcast from a roadside device  102 . At  506 , the position determining module  120  determines the current position of the vehicle  104  based upon the signals received from the GNSS satellites. At  508 , the V2X communication module  122  receives SPaT signals broadcast from the communication module  130  of one or more traffic signals  107  located within the intersection  106 . 
     At  510 , the vehicle control module  124  determines the lane (i.e., roadway) the vehicle is traveling within. For example, the vehicle control module  124  compares the current position determined by the position determining module  120  with the modified geometry data received by the V2X communication module  122 . Based upon the comparison, the vehicle control module  124  determines, or identifies, the lane in which the vehicle  104  is travelling. At  512 , the vehicle control module  124  determines whether any SPaT signals have been received corresponding to the identified lane. 
     The method returns to  506  when the vehicle control module  124  determines that no SPaT signals corresponding to the identified lane have been received. At  514 , the vehicle control module  124  may actuate the vehicle systems  126  based upon the received SPaT signal. For example, the vehicle control module  124  generates and transmits a control signal to the vehicle systems  126  to control one or more operational aspects of the vehicle  104 . At  516 , the vehicle control module  124  causes the display  128  to display information based upon the SPaT signals. For example, the vehicle control module  124  generates and transmits a display control signal to cause the display  128  to display information pertaining to the intersection  106 . The method ends at  518 . 
     The foregoing description is merely illustrative in nature and is in no way intended to limit the disclosure, its application, or uses. The broad teachings of the disclosure can be implemented in a variety of forms. Therefore, while this disclosure includes particular examples, the true scope of the disclosure should not be so limited since other modifications will become apparent upon a study of the drawings, the specification, and the following claims. It should be understood that one or more steps within a method may be executed in different order (or concurrently) without altering the principles of the present disclosure. Further, although each of the embodiments is described above as having certain features, any one or more of those features described with respect to any embodiment of the disclosure can be implemented in and/or combined with features of any of the other embodiments, even if that combination is not explicitly described. In other words, the described embodiments are not mutually exclusive, and permutations of one or more embodiments with one another remain within the scope of this disclosure. 
     Spatial and functional relationships between elements (for example, between modules, circuit elements, semiconductor layers, etc.) are described using various terms, including “connected,” “engaged,” “coupled,” “adjacent,” “next to,” “on top of,” “above,” “below,” and “disposed.” Unless explicitly described as being “direct,” when a relationship between first and second elements is described in the above disclosure, that relationship can be a direct relationship where no other intervening elements are present between the first and second elements, but can also be an indirect relationship where one or more intervening elements are present (either spatially or functionally) between the first and second elements. As used herein, the phrase at least one of A, B, and C should be construed to mean a logical (A OR B OR C), using a non-exclusive logical OR, and should not be construed to mean “at least one of A, at least one of B, and at least one of C.” 
     In the figures, the direction of an arrow, as indicated by the arrowhead, generally demonstrates the flow of information (such as data or instructions) that is of interest to the illustration. For example, when element A and element B exchange a variety of information but information transmitted from element A to element B is relevant to the illustration, the arrow may point from element A to element B. This unidirectional arrow does not imply that no other information is transmitted from element B to element A. Further, for information sent from element A to element B, element B may send requests for, or receipt acknowledgements of, the information to element A. 
     In this application, including the definitions below, the term “module” or the term “controller” may be replaced with the term “circuit.” The term “module” may refer to, be part of, or include: an Application Specific Integrated Circuit (ASIC); a digital, analog, or mixed analog/digital discrete circuit; a digital, analog, or mixed analog/digital integrated circuit; a combinational logic circuit; a field programmable gate array (FPGA); a processor circuit (shared, dedicated, or group) that executes code; a memory circuit (shared, dedicated, or group) that stores code executed by the processor circuit; other suitable hardware components that provide the described functionality; or a combination of some or all of the above, such as in a system-on-chip. 
     The module may include one or more interface circuits. In some examples, the interface circuits may include wired or wireless interfaces that are connected to a local area network (LAN), the Internet, a wide area network (WAN), or combinations thereof. The functionality of any given module of the present disclosure may be distributed among multiple modules that are connected via interface circuits. For example, multiple modules may allow load balancing. In a further example, a server (also known as remote, or cloud) module may accomplish some functionality on behalf of a client module. 
     The term code, as used above, may include software, firmware, and/or microcode, and may refer to programs, routines, functions, classes, data structures, and/or objects. The term shared processor circuit encompasses a single processor circuit that executes some or all code from multiple modules. The term group processor circuit encompasses a processor circuit that, in combination with additional processor circuits, executes some or all code from one or more modules. References to multiple processor circuits encompass multiple processor circuits on discrete dies, multiple processor circuits on a single die, multiple cores of a single processor circuit, multiple threads of a single processor circuit, or a combination of the above. The term shared memory circuit encompasses a single memory circuit that stores some or all code from multiple modules. The term group memory circuit encompasses a memory circuit that, in combination with additional memories, stores some or all code from one or more modules. 
     The term memory circuit is a subset of the term computer-readable medium. The term computer-readable medium, as used herein, does not encompass transitory electrical or electromagnetic signals propagating through a medium (such as on a carrier wave); the term computer-readable medium may therefore be considered tangible and non-transitory. Non-limiting examples of a non-transitory, tangible computer-readable medium are nonvolatile memory circuits (such as a flash memory circuit, an erasable programmable read-only memory circuit, or a mask read-only memory circuit), volatile memory circuits (such as a static random access memory circuit or a dynamic random access memory circuit), magnetic storage media (such as an analog or digital magnetic tape or a hard disk drive), and optical storage media (such as a CD, a DVD, or a Blu-ray Disc). 
     The apparatuses and methods described in this application may be partially or fully implemented by a special purpose computer created by configuring a general purpose computer to execute one or more particular functions embodied in computer programs. The functional blocks, flowchart components, and other elements described above serve as software specifications, which can be translated into the computer programs by the routine work of a skilled technician or programmer. 
     The computer programs include processor-executable instructions that are stored on at least one non-transitory, tangible computer-readable medium. The computer programs may also include or rely on stored data. The computer programs may encompass a basic input/output system (BIOS) that interacts with hardware of the special purpose computer, device drivers that interact with particular devices of the special purpose computer, one or more operating systems, user applications, background services, background applications, etc. 
     The computer programs may include: (i) descriptive text to be parsed, such as HTML (hypertext markup language), XML (extensible markup language), or JSON (JavaScript Object Notation) (ii) assembly code, (iii) object code generated from source code by a compiler, (iv) source code for execution by an interpreter, (v) source code for compilation and execution by a just-in-time compiler, etc. As examples only, source code may be written using syntax from languages including C, C++, C#, Objective-C, Swift, Haskell, Go, SQL, R, Lisp, Java®, Fortran, Perl, Pascal, Curl, OCaml, Javascript®, HTML5 (Hypertext Markup Language 5th revision), Ada, ASP (Active Server Pages), PHP (PHP: Hypertext Preprocessor), Scala, Eiffel, Smalltalk, Erlang, Ruby, Flash®, Visual Basic®, Lua, MATLAB, SIMULINK, and Python®. 
     None of the elements recited in the claims are intended to be a means-plus-function element within the meaning of 35 U.S.C. § 112(f) unless an element is expressly recited using the phrase “means for,” or in the case of a method claim using the phrases “operation for” or “step for.”