VEHICLE SENSING DEVICE

PURPOSE:To unnecessitate setting a strut on a roadside, to eliminate the obstacles of drivers and general passers-by, to be advantageous for the fine appearance of a city and to safely perform maintenance and inspection. CONSTITUTION:Bumps 11 are set on a part of a road surface 1 and vehicle passing sound is forcedly generated. The vehicle passing sound by the bumps 11 is detected by detectors 12 such as a microphone and a vibration meter, etc., amplified at an amplifier 14 and noise is removed by a filter 15. Further, the sound is smoothed at an RMS module 16 and is inputted to a CPU 17. The CPU 17 counts the number of passing vehicles per unit time by input signals and the degree of traffic jam is calculated.