Traffic flow change monitoring system

• US 5,281,964 A
• Filed: 10/04/1991
• Issued: 01/25/1994
• Est. Priority Date: 02/26/1990
• Status: Expired due to Term

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Kojima, Masahiro, Iida, Hideaki, Kamata, Joji, Itoh, Ko
• Primary Examiner(s): Peng, John K.
• Assistant Examiner(s): TONG, NINA C
• Application Number:
  US07/768,295
• Time in Patent Office: 844 Days
• Field of Search: 340/933, 340/934, 340/936, 340/937, 340/941, 340/942, 340/943
• US Class Current: 340/933
• CPC Class Codes: G08G 1/0104 Measuring and analyzing of parameters relative to traffic conditions

Abstract

A traffic flow change monitoring system is disclosed, which uses data obtained from a vehicle perceiving sensor placed on a road and which can detect a traffic congestion or an unexpected event. Since a change in traffic flow is monitored on the basis of the speeds or the like of individual vehicles and the distances between successive vehicles, it is possible to monitor a positional relationship between successively running vehicles Also, it is possible to make a prompt detection of an unexpected event such as an accident by detecting a change in relative vehicle speed difference between traffic lanes at each measurement spot.

Claims

1. A traffic flow monitoring system comprising:

a signal generating means for producing an output signal in response to vehicle perception signals generated by a vehicle perceiving sensor means disposed on a road;

vehicle perception data compilation means for producing vehicle perception data from said output signal;

vehicle perception data classification means for ranking said vehicle perception data;

inter-vehicle distance data compilation means for producing inter-vehicle distance data rom said output signal;

inter-vehicle distance data classification means for ranking said inter-vehicle distance data; and

judgement means for judging a change in traffic flow by performing a comparison of results of the ranking of said vehicle perception data and the ranking of said inter-vehicle distance data with a combinative decision value and monitoring a time-dependent change in a result of said comparison.

2. A traffic flow change monitoring system comprising:

a signal detection section for detecting a vehicle perception signal from a vehicle perceiving sensor on each of traffic lanes at each measuring spot;

inter-lane change judgement means for judging a relative change in traffic flow between the traffic lanes at each measuring spot on the basis of the vehicle perception signals detected by said signal detection section;

speed-by-location data generation means for producing vehicle speed data at each measuring spot on the basis of the vehicle perception signals perceived by said signal detection section;

condition-by-location judgement means for judging the condition of a traffic flow at each measuring spot on the basis of the vehicle speed data at each measuring spot produced by said speed-by-location data generation means;

sectional comprehensive judgement means for judging the condition of a traffic flow in a section inclusive of a plurality of measuring spots in accordance with the results of judgement by said inter-lane change judgement means and said condition-by-location judgement means; and

change judgement means for judging a change in traffic flow in accordance with the result of judgement by said sectional comprehensive judgement means.