TW201705099A - Method and system for location and status detection of traffic signs by deploying multiple detecting vehicles for detecting status of traffic signs in real time and recording dense and sparse tracks of GPS data - Google Patents

Abstract

A system for location and status detection of traffic signs is disclosed, which analyzes historic tracks of GPS in multiple detection vehicles in order to estimate a parking location and its parking time of the multiple detection vehicles at each intersection, and the passing time at the intersections as well. For detection vehicles coming from all directions at a single intersection, summing up and calculating each brief time period (for example, 3 seconds) in a day by counting the number of the detection vehicles passing the intersection and then subtracting the number of the parking time. The disclosed system detects the aforementioned summed value to determine whether a periodic change exits or not, if yes, the intersection is arranged with traffic signs; the system further calculates periodic lengths using statistical approaches for the starting and ending time of both the red and green cycles. The traffic information center issues the locations of traffic lights and periodic statuses on the aforementioned to the multiple detecting vehicles, and set up reporting conditions for the multiple detecting vehicles. When a detecting vehicle passes an intersection, the system analyzes its driving tracks and reports its GPS track in real time when a reporting condition is met, and then the traffic information center updates a traffic sign status based on the real time reporting track of the detecting vehicle and issues the status accordingly.

Description

Method and system for detecting location and status of traffic signals

The invention belongs to a method for detecting the location and status of traffic signs.

Existing methods for detecting the location and status of traffic signs mostly use the camera or camera on the probe vehicle to obtain images of the intersections to determine the location and status of the traffic signals. This traditional method requires fixed erection imaging equipment and a large amount of image processing calculations, and is suitable for companies that are willing to invest a large amount of early construction costs, such as Google, and is not suitable for the current popular smart phone applications.

In addition, the statistical probe vehicle estimates the phase of the traffic light through the position and movement parameters of the traffic sign intersection. However, this method is only applicable to denser GPS track records and may not be suitable for sparse GPS track records.

Due to the traditional use of image recognition and other methods to explore traffic light information, it is necessary to invest a large amount of early construction costs, which is actually difficult to implement.

In view of the shortcomings derived from the above-mentioned conventional methods, the inventor of the present invention has improved and innovated, and after years of painstaking research, he finally succeeded in researching and developing the method and system for detecting the location and status of traffic signs.

In order to achieve the above object, the present invention proposes a detection by the present invention. The location and status of the traffic sign provides Green Light Optimal Speed Advisory for users to save energy and reduce carbon emissions.

If we can further consider the location and real-time status of traffic signs, we can enhance the existing car navigation function. Urban road traffic is heavy, and traffic signs must be used to enable vehicles to pass through the intersections in an orderly and efficient manner. Traffic control can be divided into: (1) fixed period, different but fixed traffic light cycle and phase in different time periods; (2) dynamic cycle, dynamically changing traffic light cycle and phase according to traffic flow at that time.

The invention of the present invention can statistically analyze the historical trajectory of the probe vehicle, and obtain the position, period length and phase of the fixed-cycle traffic number.

In order to solve the problems disclosed above, the object of the present invention is to provide a method and system for detecting the location and status of traffic signs, and to search for traffic light information by using GPS trajectory data, which not only has low construction cost, but also can be combined with already collected vehicles. The GPS positioning information function system, such as the vehicle dispatch system, has the advantages of being easy to implement and saving construction costs. In the early stage of construction, statistical analysis of the historical track record of the probe vehicle can detect the position, period and phase of the traffic light. The pre-built detective vehicles can be dominated by existing GPS-equipped fleets (the GPS track record is usually sparse, such as every 30 seconds). During the service operation period, smart phones that can be expanded to all download services become probe vehicles, and the state of the traffic lights is corrected in a crowd-sourcing manner, so that a wider traffic status and status can be obtained. Compared with the traditional image recognition method, the method can also save the cost of additional equipment construction at the intersection due to the traffic department's adjustment of the traffic light management strategy.

To achieve the above object, the present invention provides a system for detecting the location and status of a traffic signal, which mainly includes a Traffic Information Center (TIC), which is used to analyze the history data of the probe vehicle stored in the Detector trajectory database. To estimate the location and time point of the surveillance vehicle historical data at each intersection and the time point of passing through the intersection, and calculate the location, cycle and phase information of the intersection traffic lights, store the results in the traffic light information database; release the traffic light position, cycle And phase information; receive the real-time return trajectory of the Detective Vehicle and store it in the Detector trajectory database to confirm whether to recalculate the traffic light information, and if so, update the traffic ticker status and release the traffic light information in the traffic light information database; at least one Detective Vehicle, It is a vehicle that travels on the road and is able to pass back the location information or abnormal conditions to the traffic information center through the on-board equipment; the Detector trajectory database is the information of the Detector trajectory received for storing the traffic information center; traffic light information The library is obtained after analyzing the traffic information center. The position, period and phase information of the traffic lights, and the equipment on the vehicle are the positioning devices of the GPS positioning device and the mobile phone.

The detection vehicle returns the location information or abnormal condition to the traffic information center, which means that when the detective vehicle passes the intersection, it analyzes whether the traffic trajectory meets the information of the traffic information center to release the traffic light information. If the match is required, the investigation vehicle returns the condition to report the return confirmation. If the traffic information center requires a return, the investigation vehicle returns the confirmation and its GPS trajectory; if the Detector's driving trajectory does not meet the TIC release data, or the red light cycle start point or the green light cycle makes the point to be tested, the report detector is returned. Its GPS track.

When the Traffic Information Centre receives the information reported by the Detective Vehicle, it determines whether to correct the traffic light information, receives the information reported by the Detective Vehicle, and confirms the information return. If there is, it does not need to correct the traffic light information; if there is no confirmation information, it will be based on the Detective Vehicle return trajectory. Recalculate traffic light position, period and phase information, and After updating the traffic light information and reward conditions and re-posting the traffic light information.

In order to achieve the above object, the present invention provides a method for detecting the location and status of a traffic signal. The steps are as follows: Step 1: Count each time interval of each intersection and obtain a C value, wherein the C value is reduced by the number of times the probe passes. Go to the number of times the vehicle is parked; Step 2: Does the correlation diagram of the C value show periodic changes, if not, it means that there is no traffic sign at the intersection; Step 3, if yes, the time series C value is folded according to the length of the cycle considered After the total value, the C value has the largest variation, which is the correct cycle length. Step 4: Estimate the red light cycle start time point according to the relationship between the detection vehicle parking position and the detection vehicle parking time point in the correct cycle. Step 5: Estimate the start time of the green light cycle according to the relationship between the parking position of the probe vehicle and the time point of the probe passing through the intersection in the correct cycle; Step 6. Record the cycle and phase of the traffic sign of the green road intersection.

In order to achieve the above object, the present invention provides a method for detecting the location and status of a traffic signal, which further includes a method for distributing and maintaining traffic light information by the traffic information center. The steps are as follows: Step 1: Release traffic light position, period, phase information and reward Condition; Step 2: Whether to receive the return of the probe vehicle, if not, go back to step 1; Step 3, if yes, confirm whether the information return is correct, and if yes, go back to step one; Step 4: If not, recalculate the traffic light cycle, phase information, and return conditions.

In order to achieve the above object, the present invention provides a method for detecting the location and status of a traffic signal, which further includes a method for detecting the position information or abnormal condition of the probe vehicle, and the steps are as follows: Step 1: Obtain the position, period, phase information of the traffic light and Return condition; Step 2: Obtain the traffic light status through the intersection trajectory, if not, report the abnormality notification and the crossing trajectory, and return to step 1; Step 3, if yes, whether it needs to return the confirmation, if not, go back to step 1; 4. If yes, return the confirmation information and go back to step one.

The invention provides a method and a system for detecting the location and state of a traffic sign, and has the following advantages when compared with other conventional technologies:

1. More accurate assessment of travel time when selecting a route. Further, the green light optimal speed recommendation application can be further provided, so that the user can achieve the purpose of energy saving and carbon reduction.

2. The location and immediate cycle status of the traffic sign can also be applied to the Cycling Knight, giving the best speed advice, allowing the Cycling Knight to avoid waiting for the red light at the intersection and reducing the exhaust emissions from the steam locomotive. Cyclists are also often using dedicated GPS navigation and route recording instruments, or equivalent mobile apps. The above recommended speed recommendations can enhance existing navigation features.

110‧‧‧Traffic Information Center

111‧‧‧Probe vehicle track database

112‧‧‧ Traffic Light Information Database

120‧‧‧Detective vehicle

S210~S260‧‧‧Detection process

S310~S340‧‧‧Transportation Information Center publishes and maintains the traffic light information process

S410~S450‧‧‧Detective vehicle return location information or abnormal situation process

Please refer to the detailed description of the present invention and the accompanying drawings, and the technical contents of the present invention and its effects can be further understood; the related drawings are: 1 is a schematic structural diagram of a method and system for detecting a location and status of a traffic signal according to the present invention; FIG. 2 is a flow chart of a method and system for detecting a location and status of a traffic signal according to the present invention; The flow information center of the method and system for the location and status of the locomotive releases and maintains the flow chart of the traffic light information; FIG. 4 is a flow chart of the method and system for detecting the location and status of the traffic locator in the present invention. Figure.

The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It is understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

Hereinafter, the present invention will be further described with reference to the accompanying drawings:

Please refer to FIG. 1 , which is a schematic structural diagram of a method and system for detecting the location and status of a traffic signal, which mainly includes a Traffic Information Center (TIC) 110, which is used to analyze the Detector trajectory database. The historical data of the survey vehicle stored in 111 is used to estimate the location and time point of the survey vehicle historical data at each intersection and the time point of passing through the intersection, and calculate the location, cycle and phase information of the traffic light at the intersection, and store the result in the traffic light information. The data library 112; publish the traffic light position, period and phase information; receive the real-time return trajectory of the probe vehicle 120 and store it in the Detector trajectory database 111, confirm whether to recalculate the traffic light information, and if so, update the traffic signal at the traffic light information database. Status and release; at least one detective vehicle 120 is a vehicle driving on the road, and is able to pass the on-board equipment to return location information or abnormal conditions to the traffic information center 110, wherein the vehicle equipment is equipped for GPS positioning The positioning device of the mobile phone and the mobile phone; the Detector trajectory database 111 is for storing the Detector trajectory data received by the traffic information center; the traffic light information database 112 is the traffic light position and period obtained after the traffic information center 110 is stored. And phase information.

Its Traffic Information Center (TIC) 110 and a plurality of Detective Vehicles 120 are placed in front of the immediate traffic light status service. The Detective Vehicle 120 transmits its driving trajectory to the Traffic Information Center (TIC) 110. The Traffic Information Center (TIC) 110 stores the exploration. The track of the car 120 is recorded in the probe track database 111. The Traffic Information Center (TIC) 110 analyzes and analyzes the historical track of the detective vehicle, and can know the intersection and phase of the intersection with traffic lights and traffic lights.

Please refer to FIG. 2, which is a flow chart of a method and system for detecting the location and status of a traffic signal according to the present invention. The steps are as follows: Step 1: S210 counts each time interval of each intersection and obtains a C value, wherein The value of C is the number of times the probe vehicle passes minus the number of probes. In step 2, the correlation diagram of the S220 C value shows periodic changes. If not, it means that there is no traffic sign at the S221 intersection; if not, S230 will time series. The C value is folded according to the length of the cycle considered, and the total C value has the largest variation, which is the correct cycle length. Step 4: S240 is based on the parking position of the probe and the parking time of the probe in the correct cycle. The relationship diagram estimates the start time of the red light cycle; step 5, S250 estimates the start time of the green light cycle according to the relationship between the parking position of the probe vehicle and the time point of the probe passing through the intersection in the correct cycle; Step 6. S260 records the cycle and phase of the traffic sign at the green intersection.

It can be seen from the above steps that the Traffic Information Center (TIC) analyzes the GPS trajectories of multiple Detective Vehicles, estimates the location and time point of the Detective Vehicle parking at each intersection, and the time point of passing the intersection. For a single intersection, the detectors from all directions, each time a small time interval (such as every 3 seconds, the time can be arbitrarily determined), the number of times the probe car stops S and the number of passes G, and each time is calculated. The difference C between the intervals G and S is as follows: C=GS

That is, Correlograms of each intersection C value are generated to determine whether a periodic change is present. If there is, there is a traffic sign at the intersection; if not, there is no traffic sign.

According to the time difference corresponding to the peak of Correlograms of C value, it is the length of the initial estimated traffic light cycle, and the correct period length is found in the interval where the initial estimated period length is positive and negative (such as 30 seconds). The C value of the time series is folded and added according to the considered cycle length. If the cycle length considered is the correct cycle length, then the total C value is folded and has the largest variance.

According to the correct traffic light cycle, the detection vehicle parking time point is folded to the time point in the cycle, and according to the corresponding map of the detection vehicle parking position and the detection vehicle parking time point, the red light cycle starting time point can be obtained.

After the same folding probe vehicle stops waiting for the red light at the intersection, the time point through the intersection, to the time point in the cycle, and then according to the corresponding map of the detection vehicle parking position and the probe vehicle passing the intersection time point in the cycle, Get the green light cycle start time point.

Referring to FIG. 3, the traffic information center of the method and system for detecting the location and status of the traffic sign is the release and maintenance of the traffic light information. The flow chart has the following steps: Step 1: S310 issues the traffic light position, period, phase information and return conditions; Step 2: S320 receives the probe search report, if not, then returns to S310 step one; Step 3, if yes, S330 confirms the information Whether the return is correct, if yes, return to step S310, step one; step four, if not, S340 recalculates the traffic light cycle, phase information, and reward condition.

It can be seen from the above steps that the traffic information center (TIC) issues the above traffic light position and cycle status to the probe vehicle, and sets the probe vehicle return condition. The red light cycle start point and the green light cycle start point may be known or to be tested, traffic The Information Center (TIC) can set a return condition, requiring the detective vehicle to report the status of the traffic light or its GPS trajectory. The Traffic Information Center (TIC) updates the status of the traffic ticker according to the trajectory of the Detective Vehicle and publishes it.

Please refer to FIG. 4 , which is a flow chart of the method and system for detecting the position and state of the traffic sign of the present invention. The steps are as follows: Step 1: S410 obtains the position, period and phase of the traffic light. Information and return conditions; Step 2: S420 meets the status of the traffic light through the intersection trajectory. If not, the S430 returns the abnormal notification and the trajectory through the intersection, and returns to step S410. Step 3: If yes, whether the S440 needs to report the return, if not, Then, step S410 is performed; step 4; if yes, the S450 returns the confirmation information, and returns to step S410.

The detective vehicle gets the traffic light position, cycle status, and return conditions. When the probe vehicle passes through the intersection, analyze whether the traffic trajectory meets the information released by the Traffic Information Center (TIC). If it is met, the prober checks whether the return condition requires a return confirmation. If there is a traffic information center requesting a return, the detective vehicle returns a confirmation and its GPS trajectory. If the vehicle's trajectory does not conform to the information released by the Traffic Information Center (TIC), or the red light cycle start point or the green light cycle makes the point to be tested, the GPS track of the probe vehicle is reported.

The detailed description of the present invention is intended to be illustrative of a preferred embodiment of the invention, and is not intended to limit the scope of the invention. The patent scope of this case.

To sum up, this case is not only innovative in terms of technical thinking, but also has many of the above-mentioned functions that are not in the traditional methods of the past. It has fully complied with the statutory invention patent requirements of novelty and progressiveness, and applied for it according to law. Approved this invention patent application, in order to invent invention, to the sense of virtue.

110‧‧‧Traffic Information Center

111‧‧‧Probe vehicle track database

112‧‧‧ Traffic Light Information Database

120‧‧‧Detective vehicle

Claims (5)

A system for detecting the location and status of a traffic signal includes: a Traffic Information Center (TIC), which includes: analyzing the history data of the probe vehicle stored in the Detector trajectory database to estimate the history of the Detective Vehicle The location and time of each stop at the intersection and the time point of passing through the intersection, and calculate the location, cycle and phase information of the intersection traffic lights, store the results in the traffic light information database; release the position, period and phase information of the traffic lights; The vehicle's real-time return trajectory is stored in the Detector's trajectory database to confirm whether to recalculate the traffic light information. If there is, the traffic signal status is updated and released in the traffic light information database; at least one Detective Vehicle is a vehicle driving on the road. And through the on-board equipment, to return location information or abnormal conditions to the traffic information center; the detective vehicle trajectory database is to store the Detector trajectory data received by the traffic information center; the traffic light information database is Store the location and cycle of traffic lights obtained after analysis of the traffic information center And phase information. For example, the device and alarm event processing system of the smart community described in claim 1 is the device for positioning the GPS positioning device and the mobile phone. A method for detecting the location and status of a traffic signal includes: step one: counting each time interval of each intersection and obtaining a C value; and step 2, whether the correlation diagram of the C value exhibits a periodic change, and if not, Indicates that there is no traffic sign at the intersection; Step 3: If yes, the time series C value is folded according to the considered cycle length, and the total C value has the largest variation, which is the correct cycle length; step 4, according to the detection vehicle parking position and the probe vehicle The relationship diagram of the parking time point in the correct cycle, estimating the starting time of the red light cycle; step 5, estimating the green light cycle start time according to the relationship between the parking position of the detecting vehicle and the passing time point of the detecting vehicle in the correct cycle Point; Step 6, remember the cycle and phase of the traffic sign of the green road junction. The method for detecting the location and status of a traffic sign as described in claim 3, wherein the C value is the number of times the probe vehicle passes minus the number of probes. A method for detecting the location and status of a traffic signal, which further includes a method for distributing and maintaining traffic light information by the traffic information center, and the steps are as follows: Step 1: Release traffic position, period, phase information, and reward conditions; Step 2: Whether to receive detection Return the vehicle, if not, go back to step one; step three, if yes, confirm whether the information return is correct, and if yes, go back to step one; step four, if not, recalculate the traffic light cycle, phase information, and return conditions.