Systems and methods for controlling traffic lights

Patent metadata

Field	Value
Publication number	US-2020184810-A1
Application number	US-202016788106-A
Country	US
Kind code	A1
Filing date	Feb 11, 2020
Priority date	Jul 25, 2018
Publication date	Jun 11, 2020
Grant date	—

Abstract

A method for controlling traffic lights is provided. The method may include obtaining historical track data of a plurality of vehicles. The method may include obtaining a congestion period. The method may include determining a discharge speed during the congestion period based on a portion of the historical track data corresponding to the congestion period. The method may further include determining an offset value based on a length of the road, the discharge speed, a cycle length of a first traffic light at the downstream intersection, a cycle length of a second traffic light at the upstream intersection, and a time length of a green light of the second traffic light being lit, and determining a signal timing of the second traffic light based on the offset value.

First claim

What is claimed is:

1 . A method implemented on a computing device having at least one processor and at least one storage device, comprising:
obtaining, from a server, historical track data of a plurality of vehicles that passed a road connecting an upstream intersection and a downstream intersection; determining, based on the historical track data, a time-space diagram; analyzing, based on the time-space diagram, a discharge wave propagated from the downstream intersection to the upstream intersection; determining, based on information related to the discharge wave, a relative time within a cycle at which the discharge wave from the downstream intersection reaches the upstream intersection; and determining an offset value of a second traffic light relative to a first traffic light based on the relative time, the first traffic light being at the downstream intersection, the second light being at the upstream intersection.

2 . The method of claim 1 , wherein the historical track data include spatial information and time information associated with the plurality of vehicles.

3 . The method of claim 2 , wherein the determining, based on the historical track data, a time-space diagram includes:
determining the time-space diagram based on the spatial information and time information associated with the plurality of vehicles.

4 . The method of claim 1 , wherein the analyzing, based on the time-space diagram, a discharge wave propagated from the downstream intersection to the upstream intersection includes:
determining a discharge speed of the discharge wave based on the time-space diagram.

5 . The method of claim 4 , wherein the determining a discharge speed of the discharge wave based on the time-space diagram includes:
obtaining, based on the time-space diagram, second historical track data corresponding to a congestion period; mapping the second historical track data to a cycle duration of the first traffic light on a second time-space diagram; and determining the discharge speed based on the second time-space diagram.

6 . The method of claim 5 , wherein the relative time is associated with the discharge speed, a length of the road, the cycle duration of the second traffic light and the offset value.

7 . The method of claim 6 , wherein the determining an offset value of a second traffic light relative to a first traffic light based on the relative time includes:
determining an offset value range that ensures the relative time is less than a green light duration of the second traffic light; and determining the offset value based on the offset value range.

8 . The method of claim 7 , wherein the offset value is greater than or equal to zero and less than the cycle duration of the second traffic light.

9 . The method of claim 7 , further comprising:
adjusting, based on the offset value, signal timing of the second traffic light such that the discharge wave from the downstream intersection reaches the upstream intersection during the green light duration of the adjusted second traffic light.

10 . A system, comprising:
at least one storage device including a set of instructions; and at least one processor in communication with the at least one storage device, wherein when executing the set of instructions, the at least one processor is directed to perform operations including:
obtaining, from a server, historical track data of a plurality of vehicles that passed a road connecting an upstream intersection and a downstream intersection;
determining, based on the historical track data, a time-space diagram;
analyzing, based on the time-space diagram, a discharge wave propagated from the downstream intersection to the upstream intersection;
determining, based on information related to the discharge wave, a relative time within a cycle at which the discharge wave from the downstream intersection reaches the upstream intersection; and
determining an offset value of a second traffic light relative to a first traffic light based on the relative time, the first traffic light being at the downstream intersection, the second light being at the upstream intersection.

11 . The system of claim 10 , wherein the historical track data include spatial information and time information associated with the plurality of vehicles.

12 . The system of claim 11 , wherein the determining, based on the historical track data, a time-space diagram includes:
determining the time-space diagram based on the spatial information and time information associated with the plurality of vehicles.

13 . The system of claim 10 , wherein the analyzing, based on the time-space diagram, a discharge wave propagated from the downstream intersection to the upstream intersection includes:
determining a discharge speed of the discharge wave based on the time-space diagram.

14 . The system of claim 13 , wherein the determining a discharge speed of the discharge wave based on the time-space diagram includes:
obtaining, based on the time-space diagram, second historical track data corresponding to a congestion period; mapping the second historical track data to a cycle duration of the first traffic light on a second time-space diagram; and determining the discharge speed based on the second time-space diagram.

15 . The system of claim 14 , wherein the relative time is associated with the discharge speed, a length of the road, the cycle duration of the second traffic light and the offset value.

16 . The system of claim 15 , wherein the determining an offset value of a second traffic light relative to a first traffic light based on the relative time includes:
determining an offset value range that ensures the relative time is less than a green light duration of the second traffic light; and determining the offset value based on the offset value range.

17 . The system of claim 16 , wherein the offset value is greater than or equal to zero and less than the cycle duration of the second traffic light.

18 . The system of claim 16 , wherein the at least one processor is further directed to perform the operations including:
adjusting, based on the offset value, signal timing of the second traffic light such that the discharge wave from the downstream intersection reaches the upstream intersection during the green light duration of the adjusted second traffic light.

19 . A non-transitory computer readable medium, comprising at least one set of instructions, wherein when executed by at least one processor of a computer device, the at least one set of instructions directs the at least one processor to perform operations including:
obtaining, from a server, historical track data of a plurality of vehicles that passed a road connecting an upstream intersection and a downstream intersection; determining, based on the historical track data, a time-space diagram; analyzing, based on the time-space diagram, a discharge wave propagated from the downstream intersection to the upstream intersection; determining, based on information related to the discharge wave, a relative time within a cycle at which the discharge wave from the downstream intersection reaches the upstream intersection; and determining an offset value of a second traffic light relative to a first traffic light based on the relative time, the first traffic light being at the downstream intersection, the second light being at the upstream intersection.

20 . The non-transitory computer readable medium of claim 19 , wherein the at least one set

Assignees

• Beijing Didi Infinity Technology & Dev Co Ltd

Inventors

• Sun Weili
• Liu Xianghong
• Zheng Jianfeng
• Zhu Jinqing

Classifications

• G08G1/095

  Traffic lights · CPC title

• G08G1/08

  according to detected number or speed of vehicles · CPC title

• G08G1/0145

  for active traffic flow control · CPC title

• G08G1/0129

  for creating historical data or processing based on historical data · CPC title

• G08G1/0133

  for classifying traffic situation · CPC title