JPH0342592A - Human body detector - Google Patents

Abstract

PURPOSE:To accurately detect even a stopped human body by providing a computing means which calculates the absolute value and deviation of the output value of an IR sensor and a human body deciding means which decides whether the result of the computation is of the human body or not. CONSTITUTION:The visual field of the IR sensor 1 is previously held directed to a prescribed direction in order to detect whether the human body exists in the range of A or not. The absolute value (a) and deviation (d) of the output of the sensor 1 are applied from the computing means. Firstly, the object is decided to be the human body if the absolute value (a) is within the range of the 1st threshold value fa1 and the 2nd threshold value fa2 smaller than this threshold value fa1 and when the deviation (d) larger than the threshold value fa1 is detected. Secondly, the human body is decided to exist within the detection range if the absolute value (a) is larger than the threshold value fa1 and when the derivation (d) larger than the 2nd threshold value fd2 larger than the threshold value fd1 is intermittently outputted. The absence of the human body is decided regardless of the value of the deviation (d) if the absolute value (a) is smaller than the threshold value fa2.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a device for detecting the presence or absence of a human body in a room or the like.

2. Description of the Related Art A conventional human body detection device of this type detects the amount of change in the output of an infrared sensor, that is, the differential value, and detects a human body when there is a change in the amount of infrared rays. In other words, it detects intrusion into a certain range.

Problems to be Solved by the Invention However, with the above-mentioned configuration in which the presence or absence of a human body is determined based on the amount of change in infrared rays, it is impossible to detect a human body if it stops within the field of view of the sensor.
There is a drawback that malfunctions may occur when the lights are turned on or off in a heater other than the human body, for example.

The present invention is intended to solve such conventional problems, and aims to accurately detect the presence or absence of a stopped human body, and to eliminate malfunctions caused by other heating elements.

Means for Solving the Problems In order to solve the above problems, the human body detection device of the present invention includes an infrared sensor, a calculation means for calculating an absolute value and a differential value of the output of the infrared sensor, and a calculation result by the calculation means. This is taken from the human body determination means that determines whether or not the image belongs to a human body.

Effect of the present invention With the above configuration, the absolute value and the differential value of the amount of infrared rays incident on the infrared sensor are calculated, and the human body determining means determines whether the object to be exhaled is a human body from a combination of these calculation results.

Example Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 shows a block diagram of the human body detection device of the present invention,
Thermopile type infrared sensor 1, this infrared sensor 1
A calculation means 2 calculates the absolute value and differential value of the output of the calculation device 2, and a human body determination means 3 determines whether the calculation result of the calculation device 2 is caused by a human body.

The operation of the above configuration will be explained based on FIGS. 2 and 3.

FIG. 2 shows the installation state indoors, and the field of view of the infrared sensor 1 is directed in a predetermined direction in order to detect whether a human body is present in the range A.

The absolute value a of the output of the infrared sensor 1 from the calculation means 2 is shown in FIG.
and the differential value d are given.

First, the absolute value a is within the range of the first threshold fa+, the first threshold fa, and the smaller second threshold fa, and the differential value d is within the first threshold fa. If fd or more is detected, it is determined that the target is a human body. The first threshold fd, is close to O and corresponds to a more or less moving object;
This is based on the fact that even if a human body stops within the field of view, it does not remain completely still.

Next, if the absolute value a is greater than the first threshold fa, it is determined that another heat generating object such as a stove exists, but in this case the differential value d is greater than the first threshold fd+. If the second threshold value fd or more is intermittently present,
It is determined that a human body exists within the detection range.

If the absolute value a is smaller than the second threshold fa□,
Regardless of the value of the differential value d, it is determined that no human body exists. The differential value d at this time is mainly due to the temporary passage of the human body.

Therefore, according to the configuration of this embodiment, it is possible to detect not only when a human body enters the field of view of the sensor indoors or the like, but also whether or not the human body is actually within the field of view with good accuracy. Therefore, if it is applied in conjunction with air conditioning equipment, it will be possible to perform fine-grained control depending on the presence or absence of a human body.

Furthermore, since a thermopile type infrared sensor is used, there is no need for a chipper like a pyroelectric type sensor, and the structure is simple and compact, and the cost is low.

Effects of the Invention As described above, the human body detection device of the present invention provides the following effects.

(1) Based on the absolute value and differential value of the output of the infrared sensor, it is determined whether it is a human body by a combination of these values, so it is possible to rationally detect a human body that is a heat generating object and has the property of moving. can.

(2) It can detect not only human bodies that enter the detection range, but also human bodies that are stationary indoors, so by linking with air conditioning equipment, fine-grained control according to the position of the human body can be performed. Can be applied.

[Brief explanation of drawings]

Fig. 1 is a block diagram of a human body detection device according to an embodiment of the present invention, Fig. 2 is a diagram showing the field of view of the sensor when the same is installed,
FIG. 3 is a diagram showing a flowchart of the operation. 1... Infrared sensor, 2... Arithmetic device, 3... Human body determination means.

Claims (1)

[Claims] A human body detection device comprising an infrared sensor, a calculation means for calculating an absolute value and a differential value of an output of the infrared sensor, and a human body determination means for determining whether a calculation result by the calculation means is that of a human body.