Reducing probe car data transmission

Abstract

A technique for reducing transmission of probe car data over a network is provided. The technique includes using a processor to receive, at one or more processors remote from the vehicle, a first set of probe car data for the vehicle, the first set of probe car data including a trigger event from a first time. The processor determines that a further set of probe car data has not been received during a second time interval. The processor also determines that a trigger event did not occur during the second time interval based on the determination that a further set of probe car data has not been received. The processor also estimates estimated probe car data for the vehicle during the second time interval based on the first set of probe car data and a non-triggering assumption.

Description

[Technical Field]

[0001] The present invention relates generally to the field of traffic tracking and forecasting, and more particularly to using trigger events to reduce the amount and frequency of probe car data transmission over a network. [Background technology]

[0002] Probe car data includes location and speed data collected by vehicles while they are traveling. Vehicle manufacturers are increasingly producing vehicles with internal sensors, such as global positioning system (GPS) units, that collect probe car data. These vehicles help determine traffic speeds, congestion, accidents, and other incidents on roads. Vehicles can also transmit this information to remote servers that track traffic conditions, calculate travel times, and generate traffic reports. Remote servers can collect probe car data from vehicles using cellular network data. When cellular networks are used, every phone in the traffic flow is a potential traffic probe and anonymous information source. The location of each phone can be tracked, and high-quality data can be extracted using algorithms. In this way, this probe car data can be utilized without installing infrastructure or special hardware in the vehicles or along the roads. Summary of the Invention

[0003] In one embodiment, the present invention discloses a computer-implemented method for reducing transmission of probe car data over a network. The method includes receiving, at a server remote from the vehicle, a first set of probe car data for the vehicle, the first set of probe car data including a trigger event from a first time interval. The method further includes detecting, at the server, that a second set of probe car data from a second time interval has not been transmitted from the vehicle. The method further includes determining that the second set of probe car data does not include the trigger event. The method further includes estimating estimated probe car data for the vehicle during the second time interval based on the first set of probe car data and a non-triggering assumption.

[0004] In another embodiment, the present invention provides a computer program product for reducing transmission of probe car data over a network. The computer program product includes one or more computer-readable storage media and program instructions stored on the one or more computer-readable storage media. The program instructions include program instructions for receiving, at a server remote from the vehicle, a first set of probe car data for the vehicle, the first set of probe car data including a trigger event from a first time. The program instructions also include program instructions for detecting, at the server, that a second set of probe car data from a second time interval has not been transmitted from the vehicle. The program instructions also include program instructions for determining that the second set of probe car data does not include a trigger event. The program instructions also include program instructions for estimating estimated probe car data for the vehicle during the second time interval based on the first set of probe car data and a non-trigger assumption.

[0005] In another embodiment, the present invention provides a computer system for reducing transmission of probe car data over a network. The computer system includes one or more computer processors, one or more computer-readable storage media, and program instructions stored on the computer-readable storage media and executed by at least one of the one or more processors. The program instructions include program instructions for receiving, at a server remote from the vehicle, a first set of probe car data for the vehicle, the first set of probe car data including a trigger event from a first time. The program instructions also include program instructions for detecting, at the server, that a second set of probe car data from a second time interval has not been transmitted from the vehicle. The program instructions also include program instructions for determining that the second set of probe car data does not include a trigger event. The program instructions also include program instructions for estimating estimated probe car data for the vehicle during the second time interval based on the first set of probe car data and a non-trigger assumption. [Brief explanation of the drawings]

[0006] [Figure 1] 1 shows a diagram of a vehicle monitoring system according to one embodiment of the present invention; [Figure 2] 2 shows a flowchart of vehicle sensor monitoring program steps executed within the system of FIG. 1 according to one embodiment of the present invention. [Figure 3] 2 shows a graph of acceleration change versus time interval for a vehicle in the system of FIG. 1 in accordance with one embodiment of the present invention. [Figure 4] 1 shows a schematic diagram of vehicle agents mapped to roads according to one embodiment of the present invention; [Figure 5] FIG. 2 illustrates a block diagram of components of a monitoring server and a vehicle in accordance with an exemplary embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0007] When probe car data is collected over a cellular network, the amount of data can be large and transmission can be expensive and burdensome. Therefore, embodiments disclosed herein selectively transmit probe car data to enable tracking, estimation, or interpolation of vehicle position, speed, acceleration, heading, or other data without requiring constant, continuous monitoring by a server over the network. The embodiments described herein rely on trigger events to determine the timing of transmission / reception of probe car data. The trigger events are selected to reduce data points while still providing sufficient information for vehicle tracking.

[0008] 1 shows a diagram of a vehicle monitoring system 100 according to one embodiment of the invention. The system 100 includes a server 102 that connects to vehicles 104 (i.e., sensors / devices connected to processors within the vehicles 104) via a network 106. The vehicles 104 include processors (CPUs) that receive and process signals from sensors within the vehicles 104-1 to determine the status of the vehicle 104-1 and its surroundings. The processors are generally collectively described herein as part of the vehicle 104, and references to the vehicle 104-1 should be understood to include processors for processing sensor signals and transmitting data over the network 106.

[0009] The network 106 may be, for example, a telecommunications network, a local area network (LAN), a wide area network (WAN) such as the Internet, or a combination of the three, and may include wired, wireless, or fiber optic connections. The network 106 may include one or more wired and / or wireless networks capable of receiving and transmitting data, voice, or video signals, or combinations thereof, including multimedia signals including voice, data, and video information. In general, the network 106 may be any combination of connections and protocols that support communication between the monitoring server 102 and other computing devices, such as the vehicles 104 in the vehicle monitoring system 100. In various embodiments, the network 106 operates locally via wired, wireless, or optical connections and may be any combination of connections and protocols (e.g., personal area network (PAN), near field communication (NFC), laser, infrared, ultrasonic, etc.). The monitoring server 102 may include any suitable computer structure for receiving and storing data. For example, the monitoring server 102 may include one or more computer-readable storage media having computer-readable program instructions thereon for causing a processor to perform aspects of the present invention.

[0010] The vehicle 104 includes sensors for recording or collecting, or recording and collecting, probe car data while traveling along the road 108. The sensors may include a GPS location device, a speedometer, an odometer, a clock, an accelerometer, a compass, a pressure sensor, or other sensors for detecting internal or external (i.e., environmental) conditions related to the vehicle 104-1. Thus, the probe car data includes current data about the position, speed, distance, time, acceleration, direction of travel, pressure, identification, or other information related to the vehicle 104-1 that can be detected by the sensors. The probe car data may also be detected by devices / sensors not directly installed within the vehicle. For example, a user's smartphone or a standalone GPS device inside the vehicle 104-1 may collect the probe car data. For simplicity of explanation, this application will refer to all devices that collect and transmit probe car data as the vehicle 104-1.

[0011] In addition to sensor data, vehicle 104-1 collects or calculates, or collects and calculates, pre-processed data as part of the probe car data. For example, vehicle 104-1 can use its detected location and match the location to an onboard map or identified roads to include map matching data or road identification data in the set of probe car data. Additionally or alternatively, vehicle 104-1 can measure distance from a starting point and include this information in the set of probe car data. Vehicle 104-1 can collect the probe car data as a set of probe car data from all sensors and all calculations over a given time interval. The time interval can be customized for the driver but is typically a short time interval, such as approximately one second. Other time intervals can also be used according to embodiments of the present invention. Once the set of probe car data has been collected or pre-processed, or collected and pre-processed, vehicle 104 includes a network connection that can transmit the set of probe car data to network 106 and monitoring server 102.

[0012] The monitoring server 102 includes a vehicle monitoring program 110 that receives sets of probe car data, monitors the status of the vehicles 104, and makes decisions about the road 108 based on the status. To accurately monitor the status, the vehicle monitoring program 110 can receive multiple sets of probe car data detected and preprocessed by the vehicles 104. However, short time intervals between sets of probe car data can congest the network 106 and increase the cost of monitoring the road 108. To reduce the burden on the network 106, the vehicle monitoring program 110 can receive probe car data only when a trigger event occurs. That is, the vehicle 104-1 can collect a set of probe car data every second or other short time interval, but the vehicle monitoring program 110 can receive a set of trigger event probe car data 112 only when a trigger event occurs on the vehicle 104-1. This reduces the amount of data transmitted over the network, thereby improving speed and reducing costs. The vehicle monitoring program 110 uses the trigger event probe car data 112 to store vehicle agents 114 on the monitoring server 102, representing the vehicles 104 and their associated location, speed, heading, etc. As will be described in more detail below, the vehicle monitoring program 110 estimates estimated probe car data 116 for time intervals during which the vehicle monitoring program 110 does not receive actual probe car data.

[0013] The trigger event probe car data 112 and the inferred probe car data 116 may be sent to a post-processing program 118, which can be used to optimize driver journeys by managing fleet operations, monitoring driver behavior, streamlining car sharing, and the like. Additionally, the post-processing program 118 can anticipate vehicle failures by monitoring usage, fuel consumption, security, and in-vehicle activity to reduce vehicle 104-1 maintenance. The post-processing program 118 can communicate back to the driver of the vehicle 104-1 to provide the driver with data that adds context and situational awareness, and to provide insight into the travel and driving behavior of each vehicle 104. The post-processing program 118 can also evaluate real-time interval data from multiple sources, including weather, geographic location, traffic, social media, and other data systems, to derive a holistic model of the vehicle 104-1 and road 108.

[0014] FIG. 2 illustrates a flowchart of steps of the vehicle monitoring program 110 executed within the system 100 of FIG. 1 in accordance with one embodiment of the present invention. During operation of the system 100, the vehicle monitoring program 110 receives a first set of probe car data from one of the vehicles 104 (e.g., one vehicle 104-1) over the network 106 (block 202). The first set of probe car data includes trigger event probe car data 112 from a first time interval having a trigger event and other sensor data detected by the vehicle 104-1. The vehicle 104-1 does not transmit the set of probe car data to the network 106 unless it experiences a trigger event. A trigger event is a condition detected by the vehicle 104-1 that is predefined to trigger transmission of the probe car data. Such conditions can be classified as "global events" or "prompt events."

[0015] Global events can include events that can detect triggering differences between two probe car data over a long time interval. For example, if the angle of road 108 changes by one degree per second, a one-degree change would not cause vehicle 104-1 to transmit triggering event probe car data 112. However, if road 108 continues to change by one degree per second for 30 seconds, vehicle 104-1 would recognize a significant 30-degree change and trigger a global event and transmission of triggering event probe car data 112. Vehicle 104-1 also triggers a global event after a predefined duration has expired. Prompt events are more immediately detected using only prompt data (e.g., the current acceleration derivative). For example, vehicle 104-1 can monitor the absolute value of the difference in acceleration between two consecutive time intervals to determine whether the difference is greater than an acceleration trigger threshold.

[0016] FIG. 3 illustrates a graph 300 of acceleration differential 302 over time interval 304 for a vehicle 104 in the system 100 of FIG. 1 , according to one embodiment of the present invention. The vehicle 104-1 tracks the current acceleration differential 306 and compares it to a threshold value 308. If the absolute value of the current acceleration differential 306 is detected to be outside the threshold value 308 (e.g., during time interval 310), the vehicle 104-1 recognizes a trigger event, and a set of trigger event probe car data 112 is transmitted to the network 106 and received by the vehicle monitoring program 110. Acceleration changes that are not outside the threshold value 308 (e.g., during time interval 312) do not trigger transmission of the trigger event probe car data 112. Similar tracking can be maintained for speed, direction of travel, or other sensor data that may indicate a trigger event. Thresholds may be programmed from known general operating conditions or customized based on the type of vehicle, the driver's driving habits, the characteristics of the road 108, or other details related to the particular vehicle 104.

[0017] Returning to FIG. 2, the vehicle monitoring program 110 monitors the vehicles 104 for incoming signals and detects that a second set of probe car data from a second time interval has not been transmitted from the vehicle 104-1 (block 204). The vehicle monitoring program 110 may have a minimum wait time interval before determining that the vehicle monitoring program 110 has not received a set of probe car data. The minimum wait time interval may be short (e.g., a time interval for collecting probe car data: 1.5 to 2 seconds), but upon its expiration, the vehicle monitoring program 110 can detect the absence of the second set of probe car data and determine that the second set of probe car data does not include a trigger event (block 206).

[0018] If the second set of probe car data is not received, the vehicle monitoring program 110 estimates estimated probe car data 116 for the vehicle 104-1 (block 208). Estimating the estimated probe car data 116 involves using the trigger event probe car data 112 and a non-trigger assumption (i.e., no trigger event occurred during the second time interval). This means, for example, that the heading angle, speed, acceleration, etc. have not changed more than permitted by the heading threshold, speed threshold, or both. In certain embodiments, the vehicle monitoring program 110 estimates a changing acceleration whose absolute value is not outside the threshold. For example, if acceleration increases from zero, triggering transmission of the trigger event probe car data 112, the vehicle monitoring program 110 calculates the current acceleration using a constant decay rate. That is, the vehicle monitoring program 110 is programmed to recognize that the acceleration of the vehicle 104-1 decreases as the vehicle 104-1 approaches cruising speed, and a constant decay rate has been found to accurately measure the behavior of many vehicles 104.

[0019] FIG. 4 shows a schematic diagram of vehicle agents 414 mapped to a road 408 according to one embodiment of the present invention. The schematic diagram does not necessarily reflect an actual implementation of vehicle agents according to all embodiments and is merely an example for the purposes of explanation of this application. In the illustrated embodiment, the vehicle monitoring program 110 receives trigger event probe car data for a first time interval. The trigger event probe car data includes (among other potential data) a location, a heading angle, and a speed, graphically represented (for illustrative purposes only) as a first vehicle agent 422, where the location is represented as a position relative to the roadway, the heading angle as an arrow direction, and the speed as an arrow length. During a second time interval, the vehicle monitoring program 110 does not receive the trigger event probe car data and estimates estimated probe car data (represented by a second vehicle agent 424) using the trigger event probe car data (represented by the first vehicle agent 422) and the non-trigger assumption that the heading angle and speed are within associated thresholds. Similarly, the vehicle monitoring program 110 does not receive trigger event probe car data for the third or fourth time interval and estimates estimated probe car data (represented by the third vehicle agent 426 and the fourth vehicle agent 428).

[0020] The vehicle monitoring program 110 can estimate the probable probe car data by eliminating potential routes based on the configuration of the road 408. That is, the vehicle monitoring program 110 can recognize alternative routes (represented by virtual vehicle agents 430), but eliminates these routes relying on the required turn change that would have accompanied vehicle 104-1's travel on the alternative route during the third time interval and the subsequent receipt of trigger event probe car data. Because the vehicle monitoring program 110 did not receive the trigger event probe car data, the vehicle monitoring program 110 estimates a straight course for the vehicle (i.e., the third vehicle agent 426 and the fourth vehicle agent 428).

[0021] FIG. 4 illustrates two possible trigger event options that may occur during the fifth time period. One option is for vehicle 104-1 to make a slight left turn along left branch 408a. Vehicle 104-1 transmits trigger event probe car data due to a change in heading 430 between the fourth heading (i.e., the heading of fourth vehicle agent 428) and the fifth heading (i.e., the heading of fifth vehicle agent 432a) being greater than a threshold. Thus, vehicle monitoring program 110 does not estimate the probe car data and records the probe car data as vehicle agent 432a. A second option shown in FIG. 4 is for vehicle 104-1 to take a straighter path along right branch 408b but still transmit trigger event probe car data due to a speed change that exceeds a threshold. If vehicle 104-1 were to perform this option during the fourth time period, vehicle monitoring program 110 would represent vehicle 104-1 as vehicle agent 432b.

[0022] Certain embodiments of the present invention may include interpolating probe car data rather than estimating it in advance. Interpolation by the vehicle monitoring program 110, in the context of FIG. 4, involves waiting between a first time interval (vehicle agent 422) and a fifth time interval (vehicle agents 432a, 432b). When trigger event probe car data is received in the fifth time interval, the vehicle monitoring program 110 interpolates the probe car data that most likely occurred between the first and fifth time intervals. In the illustrated example, it is unlikely that vehicle 104-1 would be able to make any of the turns indicated by virtual vehicle agent 430 and return to the position received by the fifth time interval, so virtual vehicle agent 430 is eliminated. Therefore, the vehicle monitoring program 110 interpolates that vehicle 104-1 traveled along the roadway as indicated by vehicle agents 424, 426, and 428.

[0023] In particular embodiments, the vehicle monitoring program 110 can determine traffic conditions in conjunction with estimating probe car data for vehicles 104 along the road 108 (block 210). Determining traffic conditions can be based on trigger event probe car data or from estimated probe car data estimated by the vehicle monitoring program 110. For example, if one or more vehicles experience a change in acceleration at a location on the road 108 where such changes in acceleration are not normally present, the vehicle monitoring program 110 can determine that an accident has occurred at that location, or that there is an obstacle in the road, or some other event has occurred. If there is a constant slowdown by many vehicles 104 along a stretch of the road 108, the vehicle monitoring program 110 can determine that an obstacle, such as a hole, crack, or bump, has occurred in that stretch. Similarly, temporary obstacles, such as debris on the road, can be determined based on the probe car data received by the vehicle monitoring program 110. The vehicle 104 can assist in determining traffic conditions by transmitting a wave flag (indicating a wave-like speed or movement of traffic, or both) rather than trigger event probe car data. That is, if vehicle 104-1 encounters a traffic congestion along road 108, vehicle 104-1 may rely on a trigger event to stop transmitting probe car data and instead periodically transmit a wave flag along with vehicle 104-1's current position. The vehicle monitoring program 110 determines whether there is a wave flag (block 212), and if so, determines that the road conditions include a traffic congestion (block 212, "Yes"). For vehicles 104 transmitting a wave flag, the vehicle monitoring program 110 may not estimate estimated probe car data 116 at all and instead only track the congestion on road 108. If vehicle monitoring program 110 does not receive a wave flag (block 212, "No"), the vehicle monitoring program 110 determines whether vehicle 104-1 is still operating.If vehicle 104-1 is still moving (block 214, "Yes"), vehicle monitoring program 110 receives another set of trigger event probe car data. If vehicle 104-1 is not moving (block 214, "No"), the method used by vehicle monitoring program 110 ends until the next iteration.

[0024] 5 illustrates a block diagram of components of a monitoring server 102 and a vehicle 104 in accordance with an exemplary embodiment of the present invention. It should be understood that FIG. 5 is intended to be an illustration of one implementation and is not intended to imply any limitation with regard to the environments in which different embodiments may be implemented. Many modifications to the depicted environments may be made.

[0025] The monitoring server 102 and the vehicle 104 each include a communications fabric 502 that provides communications between a computer processor 504, memory 506, persistent storage 508, a communications unit 510, and an input / output (I / O) interface 512. The communications fabric 502 may be implemented with any architecture designed to pass data or control information, or both, between processors (such as microprocessors, communications and network processors), system memory, peripheral devices, and any other hardware components in the system. For example, the communications fabric 502 may be implemented with one or more buses.

[0026] Memory 506 and persistent storage 508 are computer-readable storage media. In this embodiment, memory 506 includes random access memory (RAM) 514 and cache memory 516. In general, memory 506 may include any suitable volatile or non-volatile computer-readable storage media.

[0027] The vehicle monitoring program 110 is stored in persistent storage 508 of the monitoring server 102 for execution and / or access by one or more of the monitoring server's 102's respective computer processors 504 via one or more memories in memory 506. In this embodiment, persistent storage 508 includes a magnetic hard disk drive. Alternatively, or in addition to a magnetic hard disk drive, persistent storage 508 may include a solid-state hard drive, a semiconductor storage device, a read-only memory (ROM), an erasable programmable read-only memory (EPROM), a flash memory, or any other computer-readable storage medium capable of storing computer-readable program instructions or digital information.

[0028] The media used by persistent storage 508 may be removable. For example, a removable hard drive may be used for persistent storage 508. Other examples include optical and magnetic disks, thumb drives, and smart cards that are inserted into a drive for transfer to another computer-readable storage medium that is also part of persistent storage 508.

[0029] The communications unit 510, in these examples, provides for communication with other data processing systems or devices. In these examples, the communications unit 510 includes one or more network interface cards. The communications unit 510 may provide communication through the use of either or both physical and wireless communications links. The vehicle monitoring program 110 may be downloaded to the persistent storage 508 of the monitoring server 102 through the communications unit 510 of the monitoring server 102.

[0030] The I / O interface 512 allows for the input and output of data to and from other devices that may be connected to the monitoring server 102, the vehicle 104-1, or both. For example, the I / O interface 512 may provide connection to an external device 518, such as a keyboard, keypad, touchscreen, or any other suitable input device or combination thereof. The external device 518 may also include portable computer-readable storage media, such as thumb drives, portable optical or magnetic disks, and memory cards. Software and data used to implement embodiments of the present invention, such as the vehicle monitoring program 110, may be stored on such portable computer-readable storage media and loaded into the persistent storage 508 of the monitoring server 102 via the I / O interface 512 of the vehicle 104-1. Software and data used to implement embodiments of the present invention may be stored on such portable computer-readable storage media and loaded into the persistent storage 508 of the vehicle 104-1 via the I / O interface 512 of the vehicle 104-1. The I / O interface 512 is also connected to a display 520.

[0031] Display 520 provides a mechanism for displaying data to a user and may be, for example, a computer monitor.

[0032] The programs described herein are identified based on the application for which they are implemented in particular embodiments of the invention. However, it should be understood that any particular program nomenclature herein is used merely for convenience, and thus the invention should not be limited to use in any particular application identified and / or implied by such nomenclature.

[0033] The present invention may be implemented as a system, method, or computer program product, or a combination thereof, at any possible level of technical detail. The computer program product may include one or more computer-readable storage media having computer-readable program instructions for causing a processor to perform aspects of the present invention.

[0034] A computer-readable storage medium may be a tangible device that can hold and store instructions for use by an instruction-execution device. A computer-readable storage medium may be, for example, but not limited to, an electronic storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any suitable combination of the above. A non-exhaustive list of more specific examples of computer-readable storage media includes portable computer diskettes, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), static random access memory (SRAM), portable compact disc read-only memory (CD-ROM), digital versatile disc (DVD), memory stick, floppy disk, mechanical coding devices such as punch cards or raised groove structures with recorded instructions, and any suitable combination of the above. Computer-readable storage medium, as used herein, should not be construed as a transitory signal per se, such as a radio wave or other freely propagating electromagnetic wave, an electromagnetic wave propagating through a waveguide or other transmission medium (e.g., a light pulse through a fiber optic cable), or an electrical signal transmitted through an electrical wire.

[0035] The computer-readable program instructions described herein can be downloaded from a computer-readable storage medium into each computing / processing device, or can be downloaded to an external computer or storage device, for example, via the Internet, a local area network, a wide area network, or a wireless network, or a combination thereof. The network can include copper transmission cables, fiber optic transmissions, wireless transmissions, routers, firewalls, switches, gateway computers, or edge servers, or a combination thereof. A network adapter card or network interface in each computing / processing device receives the computer-readable program instructions from the network and transfers the computer-readable program instructions to a computer-readable storage medium in the respective computing / processing device for storage.

[0036] The computer-readable program instructions for carrying out the operations of the present invention can be either assembler instructions, instruction set architecture (ISA) instructions, machine language instructions, machine-dependent instructions, microcode, firmware instructions, state setting data, configuration data for integrated circuits, or source or object code written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Smalltalk or C++, and conventional procedural programming languages ​​such as the "C" programming language or similar programming languages. The computer-readable program instructions may execute entirely on the user's computer, partially on the user's computer as a stand-alone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the latter scenario, the remote computer may be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., via the Internet using an Internet Service Provider). In some embodiments, electronic circuitry, including, for example, a programmable logic circuit, a field programmable gate array (FPGA), or a programmable logic array (PLA), can execute computer-readable program instructions by utilizing state information in the computer-readable program instructions to individualize the electronic circuitry to implement aspects of the present invention.

[0037] Aspects of the present invention are described herein with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems) and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer-readable program instructions.

[0038] These computer-readable program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, or other programmable data processing apparatus to produce a machine, whereby the instructions executed by the processor of the computer or other programmable data processing apparatus create means for implementing the functions / acts specified in one or more blocks of the flowcharts and / or block diagrams. These computer-readable program instructions can also be stored in a computer-readable storage medium that can direct a computer, programmable data processing apparatus, or other device, or combination thereof, to function in a particular manner, whereby the computer-readable medium having instructions stored therein comprises an article of manufacture containing instructions that implement aspects of the functions / acts specified in one or more blocks of the flowcharts and / or block diagrams.

[0039] The computer-readable program instructions may be loaded onto a computer, other programmable data processing apparatus, or other device to cause a series of operational steps to be performed on the computer, other programmable data processing apparatus, or other device to generate a computer-implemented process, such that the instructions executing on the computer, other programmable apparatus, or other device implement the functions / acts specified in one or more blocks of the flowcharts and / or block diagrams.

[0040] The flowcharts and block diagrams in the figures illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of the present disclosure. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of instructions, including one or more executable instructions for implementing the specified logical function(s). In some alternative implementations, the functions noted in the blocks may occur out of the order noted in the figures. For example, two blocks shown in succession may actually be accomplished in one step, executed simultaneously, or substantially simultaneously, in a partially or completely overlapping manner, depending on the functionality involved, or the blocks may sometimes be executed in the reverse order. It should also be noted that each block in the block diagrams and / or flowchart diagrams, and combinations of blocks in the block diagrams and / or flowchart diagrams, may be implemented by a dedicated hardware-based system that performs the specified functions or operations, or may execute a combination of dedicated hardware and computer instructions.

Claims

1. 1. A computer-implemented method comprising: receiving, by one or more processors remote from a vehicle, a first set of probe car data for the vehicle, the first set of probe car data including trigger events detected by the vehicle during a first time interval, the trigger events being predefined conditions for triggering transmission of the probe car data; determining that no further sets of probe car data are received during a second time interval subsequent to the first time interval; determining that no trigger event occurred during the second time interval based on a determination that no further sets of probe car data were received; and estimating estimated probe car data for the vehicle during the second time interval based on the first set of probe car data and a non-trigger hypothesis indicating that no trigger event occurred during the second time interval; A method comprising:

2. The method of claim 1 , wherein the first set of probe car data includes a selection from the group consisting of: position, speed, time, heading angle, and vehicle ID.

3. The method of claim 1 , wherein the first set of probe car data includes pre-processed data selected from the group consisting of map matching data, road identification data, and measured distance from a starting point.

4. 2. The method of claim 1, wherein the first set of probe car data includes a first heading angle and a first speed, and the non-triggering assumption means that the current heading angle in the second time interval is within a heading angle threshold from the first heading angle, or that the current speed in the second time interval is within a speed threshold from the first speed, or both.

5. The method of claim 1 , wherein estimating estimated probe car data for the vehicle during the second time interval includes calculating a current acceleration using a constant decay rate for acceleration.

6. receiving a wave flag and a vehicle location at a third time interval, the wave flag including an indication of wave-like traffic movement; determining, in response to receiving the wave flag, that road conditions include congestion without estimating estimated probe car data for the third time interval; The method of claim 1 , comprising:

7. receiving, by one or more processors remote from the vehicle, a third set of probe car data for the vehicle, the third set of probe car data including a trigger event detected by the vehicle during a third time interval and being a predefined condition for triggering transmission of the probe car data; interpolating a position of the vehicle during the second time interval based on the first set of probe car data and the third set of probe car data; The method of claim 1 , comprising:

8. The method of claim 1 , wherein the trigger event comprises an absolute value of a difference in acceleration between two consecutive time intervals that is greater than an acceleration trigger threshold.

9. Estimating the position of the vehicle during the second time interval includes: calculating an estimated distance traveled by the vehicle since the time interval associated with the trigger event; calculating an estimated heading range for the vehicle, the estimated heading range including a current heading received at a remote server including the one or more processors and a heading threshold within which the one or more processors will not trigger a trigger event; comparing the estimated travel distance and the estimated travel direction range with map data stored on the remote server; The method of claim 1 , comprising:

10. The method of claim 9 , wherein the range of probable headings comprises the current heading received at the remote server plus or minus the heading threshold.

11. A computer program causing a computer to carry out the method according to any one of claims 1 to 10.

12. A computer readable storage medium having stored thereon the computer program of claim 11.

13. 1. A computer system for reducing transmission of probe car data, the computer system comprising:

11. A computer system comprising one or more computer processors, one or more computer readable storage media, and program instructions stored on the computer readable storage media that cause at least one of the one or more processors to perform a method according to any of claims 1 to 10.

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