×

Traffic signal control method

  • US 6,937,161 B2
  • Filed: 04/08/2003
  • Issued: 08/30/2005
  • Est. Priority Date: 05/13/2002
  • Status: Expired due to Fees
First Claim
Patent Images

1. A traffic signal control method for setting a green light time to a value between a lower limit time and an upper limit time in real time depending on a traffic volume sensed by a vehicle sensor, wherein:

  • an evaluation value is found for each phase, the evaluation value being a sum of the traffic volume in a past cycle and a set value given to the number of vehicles waiting on a red light in a case where the green light time in a last cycle had reached the upper limit time, and in a case where the green light time in the last cycle had not reached the upper limit time, the evaluation value being the traffic volume in the past cycle; and

    a longer upper limit time is allocated to a phase in question as the evaluation value becomes greater, and a shorter upper limit time is allocated to the phase in question as the evaluation value becomes smaller.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×