Signal control system, apparatus, method, and computer-readable medium

A signal control method comprising:

• detecting a vehicle present in a lane from which a vehicle entering an intersection at which a traffic light is installed from a first direction crosses an opposite lane and turns left, and a vehicle entering the lane;
• measuring a flow of traffic of an oncoming vehicle that travels in the opposite lane from a second direction opposite to the first direction, enters the intersection, and passes through the intersection;
• acquiring a traffic condition comprising a speed of the oncoming vehicle based on the measured flow of the traffic of the oncoming vehicle;
• acquiring an intersection entry time indicating a time until the oncoming vehicle reaches the intersection;
• predicting an intersection entry time point at which the oncoming vehicle enters the intersection based on the intersection entry time;
• controlling a timing of a signal indication for facilitating the left turn-in controlling signal indications of a first traffic light and a second traffic light configured to control traffic of vehicles entering the intersection from the first direction and the second direction, respectively, based on the predicted intersection entry time point and a time point corresponding to a predetermined timing for starting the signal indication for facilitating the left turn in a signal indication cycle;
• determining, based on the predicted intersection entry time point, whether or not the oncoming vehicle enters the intersection until a time point at which passage on the straight traveling side is not allowed;
• and
• determining, in a case where it is determined that the oncoming vehicle does not enter the intersection until the time point at which passage on the straight traveling side is not allowed, to advance the timing of the signal indication for facilitating the left turn.

A non-transitory computer-readable medium storing a program for causing a computer to execute a process comprising:

• detecting a vehicle present in a lane from which a vehicle entering an intersection at which a traffic light is installed from a first direction crosses an opposite lane and turns left, and a vehicle entering the lane;
• measuring a flow of traffic of an oncoming vehicle that travels in the opposite lane from a second direction opposite to the first direction, enters the intersection, and passes through the intersection;
• acquiring a traffic condition comprising a speed of the oncoming vehicle based on the measured flow of the traffic of the oncoming vehicle;
• acquiring an intersection entry time indicating a time until the oncoming vehicle reaches the intersection;
• predicting an intersection entry time point at which the oncoming vehicle enters the intersection based on the intersection entry time;
• controlling a timing of a signal indication for facilitating the left turn in controlling signal indications of a first traffic light and a second traffic light configured to control traffic of vehicles entering the intersection from the first direction and the second direction, respectively, based on the predicted intersection entry time point and a time point corresponding to a predetermined timing for starting the signal indication for facilitating the left turn in a signal indication cycle;
• determining, based on the predicted intersection entry time point, whether or not the oncoming vehicle enters the intersection until a time point at which passage on the straight traveling side is not allowed;
• and
• determining, in a case where it is determined that the oncoming vehicle does not enter the intersection until the time point at which passage on the straight traveling side is not allowed, to advance the timing of the signal indication for facilitating the left turn.