초록 ▼

The present invention provides a method and detection system for determining whether a person or other animate body is present in a vehicle by analyzing the power of the output signal from a geophone placed in contact with the vehicle structure. First an electrical signal is obtained which is a func

The present invention provides a method and detection system for determining whether a person or other animate body is present in a vehicle by analyzing the power of the output signal from a geophone placed in contact with the vehicle structure. First an electrical signal is obtained which is a function of the vibrations emanating from the structure, and this signal is sampled on a contiguous basis over a plurality of time periods of equal duration. From these samples, a determination is then made as to whether a dense accumulation of power exists in the vicinity of the lowest power point of the sampled time periods and whether this lowest power point is above a predetermined minimum level. The system for accomplishing this method may include a seismic transducer used as a sensing device and a micro-computer for processing the output signals from the seismic transducer. The micro-computer will, on a continguous basis, sample about 2⅔ seconds of data at a time. The total power from each of these 2⅔ second data segments is calculated. If the computer sees that there is a dense accumulation of power at the lowest power point and above and that this is larger than a minimum requirement, then it will signal the presence of one or more concealed persons. There is a variable operating time as the computer continuously accumulates new data and, hence, new power points. It will collect data until it has sufficient information to make a reliable decision. In a quiet environment this may be 6-10 seconds whereas, in a noisy environment it may be two minutes or longer.

대표청구항 ▼

A time domain power evaluation method for detecting the presence of an animate body in an inanimate mobile structure which includes: a. sensing the mechanical vibrations emanating from a mobile structure and deriving therefrom an electrical signal which is a function of such vibrations; b. sampling

A time domain power evaluation method for detecting the presence of an animate body in an inanimate mobile structure which includes: a. sensing the mechanical vibrations emanating from a mobile structure and deriving therefrom an electrical signal which is a function of such vibrations; b. sampling said electrical signal during a plurality of equal time periods and obtaining the power level of said sampled electrical signal during said equal time periods; c. determining whether an accumulation of power levels of a selected magnitude exists within a selected power range of power levels close to but above the lowest power level obtained during said sampled time periods; d. determining whether said lowest power level is above a predetermined minimum power level; e. and providing an output indication in the presence of an accumulation of power levels at or in excess of said selected magnitude in said selected power range when said lowest power level is above said predetermined minimum power level.