Intersection phase map
Methods and apparatus are disclosed for providing information about road features. A server can receive reports from information sources associated with a road feature that can include a road intersection. Each report can include source data obtained at a respective time. The source data from the reports can be stored at the server. The server can construct a phase map, where the phase map is configured to represent a status of the road feature at one or more times. The server can receive an information request related to the road feature at a specified time. In response to the information request, the server can generate an information response including a prediction of a status related to the road feature at the specified time. The prediction can be provided by the phase map and is based on information request. The information response can be sent from the server.
1. A method comprising:
receiving, at a server from at least one information source, data related to a traffic signal controlling traffic through a road intersection being approached by a vehicle;
determining, based on the data, a current status of the traffic signal and a prediction of future status of the traffic signal at one or more future times, wherein the prediction of future status of the traffic signal includes indicating a beginning time and an end time between which the traffic signal will display a particular color;
determining that, for the traffic signal controlling traffic through the road intersection, a drift has occurred between two adjacent days in the beginning time at which the traffic signal will display the particular color;
determining an amount of the drift in the beginning time between the two adjacent days;
determining a level of certainty for the prediction of future status of the traffic signal, wherein the level of certainty is based at least on the determined amount of drift;
receiving, at the server, an information request by the vehicle related to the road intersection;
in response to the information request, the server generating information including the current status of the traffic signal, the prediction of future status of the traffic signal at a specified time at which the vehicle reaches the road intersection, and the level of certainty; and
sending the information to the vehicle.
2. The method of claim 1 , wherein the prediction of the future status comprises a predicted red/yellow/green-light status of the traffic signal at the specified time at which the vehicle reaches the intersection.
3. The method of claim 1 , wherein generating the information in response to the information request comprises:
obtaining one or more data items from the data; and
for each data item of the one or more data items:
determining an age of the data item,
comparing the age of the data item to a threshold age, and
in response to the age of the data item being less than the threshold age, using the data item to determine the response data.
4. The method of claim 3 , wherein the traffic signal is configured to sequence through a series of signals during a predetermined traffic-cycle time, and wherein the threshold age is based on the traffic-cycle time.
5. The method of claim 1 , wherein the level of certainty indicates a period of time different from a respective period of time between the beginning time and the end time.
6. The method of claim 1 , further comprising:
receiving additional data related to a plurality of objects at or proximate to the road intersection being approached by the vehicle;
determining, based on the additional data, a current status of the plurality of objects relative to the road intersection and a prediction of future status of the plurality of objects relative to the road intersection at the one or more future times;
determining a respective level of certainty for the prediction of future status of the plurality of objects, wherein the information generated in response to the information request further includes the current status of the plurality of objects relative to the road intersection, the prediction of future status of the plurality of objects relative to the road intersection at the specified time at which the vehicle reaches the road intersection, and the respective level of certainty.
7. The method of claim 6 , wherein the prediction of the future status of the plurality of objects comprises a prediction of whether an object of the plurality of objects will be in a path of the vehicle at the specified time at which the vehicle reaches the intersection.
8. The method of claim 6 , wherein the additional data comprises one or more of: data about another vehicle at or proximate to the road intersection, data about a pedestrian crossing or about to cross the road intersection, data about road construction proximate to the road intersection, and data about a blockage of the road intersection.
9. The method of claim 6 , wherein the plurality of objects includes an object approaching the road intersection, wherein the prediction of future status of the plurality of objects relative to the road intersection indicates whether the object will obstruct the vehicle at specified time at which the vehicle reaches the road intersection, and wherein the respective level of certainty represents a probability that the object will obstruct the vehicle at the specified time.
10. A server, comprising:
a processor; and
non-transitory computer readable medium having stored thereon executable instructions that, upon execution by the server, cause the server to perform operations comprising:
receiving, from at least one information source, data related to a traffic signal controlling traffic through a road intersection being approached by a vehicle;
determining, based on the data, a current status of the traffic signal and a prediction of future status of the traffic signal at one or more future times, wherein the prediction of future status of the traffic signal includes indicating a beginning time and an end time between which the traffic signal will display a particular color;
determining that, for the traffic signal controlling traffic through the road intersection, a drift has occurred between two adjacent days in the beginning time at which the traffic signal will display the particular color;
determining an amount of the drift in the beginning time between the two adjacent days;
determining a level of certainty for the prediction of future status of the traffic signal, wherein the level of certainty is based at least on the determined amount of drift;
receiving an information request by the vehicle related to the road intersection;
in response to the information request, generating information including the current status of the traffic signal, the prediction of future status of the traffic signal at a specified time at which the vehicle reaches the road intersection, and the level of certainty; and
sending the information to the vehicle.
11. The server of claim 10 , wherein the prediction of the future status comprises a predicted red/yellow/green-light status of the traffic signal at the specified time at which the vehicle reaches the intersection.
12. The server of claim 10 , wherein generating the information in response to the information request comprises:
obtaining one or more data items from the data; and
for each data item of the one or more data items:
determining an age of the data item,
comparing the age of the data item to a threshold age, and
in response to the age of the data item being less than the threshold age, using the data item to determine the response data.
13. The server of claim 12 , wherein the traffic signal is configured to sequence through a series of signals during a predetermined traffic-cycle time, and wherein the threshold age is based on the traffic-cycle time.
14. The server of claim 10 , wherein the level of certainty indicates a period of time different from a respective period of time between the beginning time and the end time.
15. A non-transitory computer readable medium having stored thereon executable instructions that, upon execution by a server, cause the server to perform operations comprising:
receiving, from at least one information source, data related to a traffic signal controlling traffic through a road intersection being approached by a vehicle;
determining, based on the data, a current status of the traffic signal and a prediction of future status of the traffic signal at one or more future times, wherein the prediction of future status of the traffic signal includes indicating a beginning time and an end time between which the traffic signal will display a particular color;
determining that, for the traffic signal controlling traffic through the road intersection, a drift has occurred between two adjacent days in the beginning time at which the traffic signal will display the particular color;
determining an amount of the drift in the beginning time between the two adjacent days;
determining a level of certainty for the prediction of future status of the traffic signal, wherein the level of certainty is based at least on the determined amount of drift;
receiving an information request by the vehicle related to the road intersection;
in response to the information request, generating information including the current status of the traffic signal, the prediction of future status of the traffic signal at a specified time at which the vehicle reaches the road intersection, and the level of certainty; and
sending the information to the vehicle.
16. The non-transitory computer readable medium of claim 15 , wherein the prediction of the future status comprises a predicted red/yellow/green-light status of the traffic signal at the specified time at which the vehicle reaches the intersection.
17. The non-transitory computer readable medium of claim 15 , wherein generating the information in response to the information request comprises:
obtaining one or more data items from the data; and
for each data item of the one or more data items:
determining an age of the data item,
comparing the age of the data item to a threshold age, and
in response to the age of the data item being less than the threshold age, using the data item to determine the response data.
18. The non-transitory computer readable medium of claim 17 , wherein the traffic signal is configured to sequence through a series of signals during a predetermined traffic-cycle time, and wherein the threshold age is based on the traffic-cycle time.
19. The non-transitory computer readable medium of claim 15 , wherein the level of certainty indicates a period of time different from a respective period of time between the beginning time and the end time.
20. The non-transitory computer readable medium of claim 15 , wherein the operations further comprise:
receiving additional data related to a plurality of objects at or proximate to the road intersection being approached by the vehicle;
determining, based on the additional data, a current status of the plurality of objects relative to the road intersection and a prediction of future status of the plurality of objects relative to the road intersection at the one or more future times;
determining a respective level of certainty for the prediction of future status of the plurality of objects, wherein the information generated in response to the information request further includes: the current status of the plurality of objects relative to the road intersection, the prediction of future status of the plurality of objects relative to the road intersection at the specified time at which the vehicle reaches the road intersection, and the respective level of certainty.