JPH10160028A - Object sensing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily control a device even by means of a microcomputer with comparatively low performance by arranging a simple computation processing means which performs computation based on plural data indicated by reflection waves so as to determine presense of an object while utilizing the former computation results. SOLUTION: A device of this type has a valve driving part 3, a signal processing part 5 which controls a sensor 1 and the valve driving part 3, and a dc power source 7. A microcomputer 29 of the signal processing part 5 has a CPU performing computation for controlling each part, and memories for housing controlling programs and required data. By this computation process, a voltage signal from a sensor circuit is binarized, and stored in the memory as the newest data. This process is composed of calculation obtaining first distribution (distribution 1) from the former calculated value, and calculation obtaining second distribution (distribution 2) from data in each memory. Determination is performed by comparing the distribution 1 with a threshold value 1, and check-calculating the distribution 1 by means of the distribution 2. This device can easily be controlled by a microcomputer with compalatively low performance.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention generally relates to an object detection device, and more particularly to an object detection device that detects the approach or departure of an object by using a reflected wave of a propagation wave such as light.
In this specification, a human body is described as an example of an object.

[0002]

2. Description of the Related Art Conventionally, in an automatic water supply device, a hot water washing device and an automatic faucet device, a device using a reflection type non-contact active sensor as an object detection device is known. In particular, in an automatic faucet device, when an object detecting device installed on a wash basin or the like detects an object such as a hand below a spout (spout) of the wash basin, the faucet is automatically opened to discharge water from the spout. Are well known. In this device, the object detection device emits a propagating wave such as light or ultrasonic wave toward the lower part of the spout, measures its reflection level, and detects an object existing below the spout based on a comparison result of this level and a threshold value. Like that.

[0003]

By the way, in the case of an automatic water supply device or a hot water washing device, in addition to the propagation wave reflected from the detection target object, the propagation wave reflected on the surrounding wall returns to the object detection device. There is a problem that the presence or absence of the detection target object cannot be confirmed unless the level correction of the reflected wave, the update of the threshold value, and the like are performed. Also, in the case of the automatic faucet device, similarly to the above, in addition to the propagation wave reflected from the detection target object, there is a problem that the propagation wave reflected on the bottom inside the bowl of the wash basin returns to the object detection device. In addition, water discharged from the spout, dirt on the bowl, changes over time in the bowl, and the like adversely affect object detection as disturbance. Therefore, there is a problem that the presence or absence of the detection target object cannot be confirmed unless the level correction of the reflected wave, the update of the threshold value, and the like are performed.

[0004] As a means for solving the above-mentioned problem, a method of statistically processing the level of a reflected wave returning to an object detection device to determine the presence or absence of an object to be detected has been filed (Japanese Patent Application No. 2002-110,197). Hei 5-536916).

However, in the method of determining the presence or absence of an object to be detected by statistical processing of sensor output, sensor data is periodically input and stored, and a statistical value is calculated for a plurality of stored data. The method has the following problems.

That is, in the method according to the above-mentioned application, a signal relating to reflected light having a relatively large level change indicating a user's hand movement, spouting water from a spout, and the like, and a relatively level signal indicating reflection from a wash bowl. The principle is to determine the distinction from the signal related to the reflected light with little change based on variance or the magnitude or continuity of the value of the standard deviation. However, when calculating a variance value from N sensor data, for example, many arithmetic processes such as a total value, a sum of squares, and division of the N data are required. These arithmetic processings are generally performed by a microcomputer (= microcomputer). However, in the case of a control circuit of a product such as an automatic faucet, the control target is only a sensor circuit or a solenoid valve, and the control itself is performed. Is relatively simple, so very high-performance microcomputers are not used.

That is, most microcomputers of about 4 bits which are often used as a control circuit of this type of device are mainly designed for sequence control, and generally have low arithmetic processing capabilities, and are particularly suitable for multiplication and division. It requires much longer operation time than addition or subtraction. In the case of the method of statistically processing the sensor data as described above, it is necessary to drive the sensor periodically, and the interval of the cycle is the time that can be used for the above calculation, etc. Most of the time may be used for statistical processing of sensor data.

Therefore, for example, when it is necessary to read a signal from a switch for giving a drive command signal to a microcomputer or to control the operation mode display of the apparatus, it is difficult to allocate a sufficient time to the control. If the time required for the statistical processing is longer than the driving cycle of the sensor, the control method itself will not be established. In the case of a device using a battery as a driving power source, a method is used in which the execution of a program is stopped to reduce the power consumption of the microcomputer during a period in which the operation of the microcomputer is unnecessary. , The effect of the suppression is reduced.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to reduce the complexity of arithmetic processing as much as possible so that control is not hindered even when a microcomputer having a relatively low processing capability is used.

[0010]

An object detection apparatus according to a first aspect of the present invention receives a reflected wave of a transmitted propagation wave,
A simplified arithmetic processing means for determining the presence or absence of an object based on the value of the reflected wave, and performing an arithmetic process based on a plurality of data indicating the value of the reflected wave using the result of the previously performed arithmetic process .

According to this configuration, since the arithmetic processing based on the plurality of data indicating the value of the reflected wave is performed using the result of the arithmetic processing performed last time, the number of data to be processed increases. However, the time required for the arithmetic processing increases accordingly, and the time for the arithmetic processing does not increase.

In a preferred embodiment according to the first aspect of the present invention, the result of the arithmetic processing is the oldest data among all data obtained by previously sampling the signal indicating the level of the reflected wave. It is obtained by statistical processing including removal and addition of the latest data. This statistical processing also includes a variance calculation performed based on a total value calculation of a plurality of sampled data and a square sum calculation of each data.

In this embodiment, the simplified arithmetic processing means calculates the variance of a plurality of data indicating the level of the reflected wave using the result of the previously performed arithmetic processing.

In this embodiment, every time the simplified calculation processing by the simplified calculation processing means is repeated a predetermined number of times, a plurality of data indicating the level of the reflected wave are all obtained, and the oldest data is removed from the data. After addition of the latest data, standard calculation processing means for calculating the variance based on the sum of these data and the sum of squares operation may be further provided. When the result of the arithmetic processing by the simplified arithmetic processing means is different from the result of the arithmetic processing by the standard arithmetic processing means, an invalidating means for invalidating the result of the arithmetic processing by the simplified arithmetic processing means may be further provided.

According to this configuration, even if an error occurs due to disturbance or the like in the calculation processing result or the like by the simplified calculation processing means, the error can be checked with the highly reliable calculation processing result by the standard calculation processing means. The resulting arithmetic processing result can prevent the device from malfunctioning for a long time.

[0016] The water control device according to the second aspect of the present invention comprises:
The reflected wave of the transmitted propagation wave is received, and the water supply is controlled according to the determination result of the presence or absence of the object based on the value of the reflected wave, and the arithmetic processing based on a plurality of data indicating the level of the reflected wave is performed. , Simple operation processing means for executing using the result of the operation processing performed last time.

In a preferred embodiment according to the second aspect of the present invention, the arithmetic processing result is the oldest data among all the data obtained by sampling the signal indicating the level of the reflected wave in the previous time. It is obtained by statistical processing including removal and addition of the latest data. This statistical processing also includes a sum calculation of a plurality of sampled data and a variance calculation performed based on a square sum calculation of each data.

The simplified arithmetic processing means calculates the variance of a plurality of data indicating the level of the reflected wave using the result of the arithmetic processing performed last time.

In the above arrangement, every time the simplified operation processing by the simplified operation processing means is repeated a predetermined number of times, all of a plurality of data indicating the level of the reflected wave are acquired, the oldest data is removed from the data, and the latest data is removed. After addition of the data, the standard operation processing means for calculating the variance based on the sum calculation of these data and the sum of squares operation may be further provided.

In addition, when the result of the arithmetic processing by the simplified arithmetic processing means is different from the result of the arithmetic processing by the standard arithmetic processing means, it is possible to further comprise invalidating means for invalidating the result of the arithmetic processing by the simplified arithmetic processing means. .

A program medium according to a third aspect of the present invention is for an object detection device that receives a reflected wave of a transmitted propagation wave and determines the presence or absence of an object based on the value of the reflected wave. A computer-readable program for causing a computer to function as a simplified arithmetic processing unit that executes arithmetic processing based on a plurality of data indicating a wave level by using a result of the previous arithmetic processing is stored.

The simplified arithmetic processing means according to the present invention can be typically realized by a programmed microcomputer. The program for this is supplied to the processor of the microcomputer by a semiconductor memory or another form of program medium.

[0023]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 shows a circuit configuration of a water control apparatus according to one embodiment of the present invention.

This water control device is installed in a water circulating facility such as a wash basin or a hand-washing sink in a toilet room.

As shown in the figure, the above device drives a sensor unit 1 for detecting a hand or the like which is a part of a human body and a valve (not shown) for opening / closing an automatic faucet (not shown). The apparatus includes a valve driving section 3, a signal processing section 5 for controlling the sensor section 1 and the valve driving section 3, and a DC power supply 7 for supplying power to the above-described sections.

The sensor section 1 comprises a light emitting element 9 and a light receiving element 1
1, a sensor circuit 13, and a transistor 15.

The light emitting element 9 is composed of a light emitting diode, and when the sensor circuit 13 is in a driving state,
It is driven by being supplied with power from the DC power supply 7 through the transistor 15 and the sensor circuit 13, and emits predetermined light such as infrared light or visible light at a predetermined angle.

The light receiving element 11 is made of, for example, a photodiode. When the sensor circuit 13 is in a driving state, the light receiving element 11 is driven by being supplied with power from the DC power supply 7 through the transistor 15 and the sensor circuit 13 and is driven. A current (photocurrent) having a magnitude corresponding to the light quantity is output.

The sensor circuit 13 is activated when the transistor 15 is turned on and a command signal is outputted from a microcomputer (microcomputer) 29 described later, and drives the light emitting element 9 and the light receiving element 11. Then, by detecting the level of the reflected light received by the light receiving element 11 and performing predetermined signal processing, a voltage signal (analog signal) corresponding to the level of the reflected light is generated and output.

The transistor 15 performs a switching operation based on a control signal from the microcomputer 29, and cuts off / continues supply of drive power from the DC power supply 7 to the sensor circuit 13.

The valve driving section 3 has a latching solenoid 17 for driving the above-mentioned valve (not shown).
And an H-bridge circuit 27 including four transistors 19 to 25, each of which performs a switching operation based on a command signal from the microcomputer 29.

When the H-bridge circuit 27 forms a closed loop from the DC power supply 7 to the DC power supply 7 via the transistor 21, the solenoid 17, and the transistor 23 by turning on the transistors 21 and 23, for example, the solenoid 17 A valve (not shown) is driven in the opening direction. Conversely, when the transistors 19 and 25 are both turned on to form a closed loop from the DC power supply 7 to the DC power supply 7 via the transistor 19, the solenoid 17, and the transistor 25, the solenoid 17 is turned on by a valve (not shown). Are driven in the closing direction.

The signal processing section 5 comprises a microcomputer 29, an oscillator 31, and a reset circuit 33.

The oscillator 31 generates a clock pulse necessary for the operation of the microcomputer 29 and outputs the clock pulse to the microcomputer 2.
9 is output.

The reset circuit 33 includes a reset signal output terminal 29a and a reset signal input terminal 29 of the microcomputer 29.
b, and is activated by a reset signal output from a reset signal output terminal 29a to
It is configured to apply a hard reset to.

The microcomputer 29 controls the sensor circuit 13, the transistor 15, and the transistors 19 to 25 constituting the H-bridge circuit 27. The microcomputer 29 includes a CPU for performing an arithmetic processing operation for controlling these components. A memory that stores control programs and stores necessary data,
An input / output unit (both not shown) is provided.

The microcomputer 29 outputs a control signal for turning on the transistor 15 and outputs a predetermined command signal to the sensor circuit 13 to activate the sensor circuit 13 and set a water discharge condition by the sensor unit 1. Perform necessary arithmetic processing. This arithmetic processing includes a process of binarizing the voltage signal output from the sensor circuit 13, a process of storing the binarized data (= reflected light level data) in the memory as the latest data, and a process of calculating from the previous calculated value. The process includes a process of obtaining a first variance (= variance 1), a process of obtaining a second variance (= variance 2) from each data in the memory, and the like. This calculation process will be described later in detail with reference to FIGS.

When the variance 1 is greater than or equal to the threshold 1, the microcomputer 29 determines that water discharge is required, and executes necessary processing based on the determination result. On the other hand, when the variance 1 is smaller than the threshold 1, it is determined that water is not required to be discharged, and necessary processing is executed based on the determination result. This calculation process will also be described later in detail with reference to FIGS. 2, 6, and 7.

Next, the control operation of each part of the water control device by the microcomputer 29 will be described with reference to the flowchart of FIG.

In FIG. 2, when the drive power of the apparatus is turned on, processing for reset and initialization is executed (steps S101 and S102), and thereafter, the time (for example, 125 msec) of the main routine shown in FIG. A timer (not shown) for management is reset (initialized) (step S103). Next, the processing operation shown in FIG. 3, which is a subroutine for setting the water discharge condition by the detection operation of the sensor unit 1, is executed (step S104).
Hereinafter, this subroutine will be described with reference to FIG.

In FIG. 3, first, the drive power is supplied to the sensor circuit 13 by turning on the transistor 15 (step S118), and the sensor circuit 13 is activated by outputting a command signal to the sensor circuit 13.
Thus, the light emitting element 9 and the light receiving element 11 are driven (step S119). Here, the sensor circuit 13
After receiving the command signal, the light emitting element 9 is driven and the light receiving element 1 is driven.
It takes 1 msec to generate and output a voltage signal corresponding to the light receiving level of one reflected light. Therefore, after outputting the command signal to the sensor circuit 13, it waits for 1 msec (step S120), reads this voltage signal and binarizes it (A
/ D conversion) (step S121). Then, the power supply to the sensor circuit 13 is stopped by turning off the transistor 15 (step S122), and the binarized data is stored in the memory as the latest data (step S123).

Returning to the main routine of FIG. 2 again, it is a subroutine of a first variance calculation for obtaining a variance 1 from the total value of all data obtained last time and the sum of squares of all data obtained last time. The processing operation shown in FIG. 4 is executed (step S105). Hereinafter, this subroutine will be described with reference to FIG.

In FIG. 4, first, the first total value of all the previous data (= the previous total value 1) is read from the memory.
The oldest data is subtracted from this total value 1 and the latest data is added, and this is added to the first total value (=
The current total value is 1) (step S124). Similarly, the first sum of squares of all the previous data (= the previous sum of squares 1) is read from the memory, the sum of squares of the oldest data is subtracted from the sum of squares 1, and the sum of squares of the latest data is added. This is defined as the first sum of squares of all data this time (= sum of current squares 1) (step S125). Next, from the current total value 1 and the current sum of squares 1, the current first variance (=
After obtaining the current variance 1) (step S126), FIG.
Return to the main routine.

Returning again to the main routine of FIG. 2, the counter A (not shown) in the microcomputer 29 is incremented (step S106). Here, the counter A
Is for measuring a fixed cycle, and one cycle is 125
It is incremented each time the main routine of msec ends. Next, it is checked whether the count value of the counter A is 480 or more (step S1).
07).

This check is performed by turning on the drive power of the apparatus and performing processing for resetting and initial setting (step S10).
1, S102) is performed to determine whether 60 seconds have elapsed. Since the cycle of the main routine of FIG. 2 is 125 msec, if the count value is 480, 125 msec × 480 = 60 sec, so it is determined that 60 seconds have elapsed (step S107).

As a result of the above check, the count value is 480
If not (ie, if it is less than 480), it is checked whether or not the current variance 1 is equal to or greater than the threshold 1 (step S10).
8). As a result of this check, if it is large, it is determined that the hand is extended under the spout, that is, it is determined that water is required to be discharged, and it is checked whether water is being discharged (step S11).
1) If it is water discharge, the process directly proceeds to step S113. If it is not water discharge, after executing the processing operation shown in FIG. 6 which is a subroutine for driving a valve (not shown) in the opening direction (step S112), step S112 is performed.
Move to 113.

On the other hand, as a result of the check in step S108, when the variance 1 is smaller than the threshold value 1, it is determined that the hand is not put under the spout, that is, it is determined that the spouting is unnecessary, and the water is stopped. Check whether there is (Step S
109) If it is still water, the process directly proceeds to step S113. If the water is not stopped, the processing operation shown in FIG. 7, which is a subroutine for driving a valve (not shown) in the closing direction, is executed (step S110), and the process proceeds to step S113.

At step S107, the count value becomes 480.
In this case, the processing operation shown in FIG. 5, which is a subroutine of the second distribution calculation for obtaining the distribution 2, is executed. In this subroutine, the main routine of FIG.
It is determined in advance that the operation is performed once every second consecutive execution. In this subroutine, a normal calculation method for obtaining a variance from the total value of all data and the sum of squares of all data is executed. In the main routine of FIG. 2, using the variance (= variance 2) obtained by this subroutine, the variance 1 obtained by the simple calculation method shown in FIG. When they do not match,
By canceling the variance 1, the reliability of the variance 1 is improved. Hereinafter, this subroutine will be described with reference to FIG.

In FIG. 5, first, all data (= D (1) to D (1) to D
(N) data of the oldest data is deleted,
Instead, the latest data is stored (step S12).
7). Next, all the above data are all added (= D (1) +
D (2) +... + D (N-1) + D (N)), and the sum thereof is defined as a second total value (= current total value 2) of all the current data (step S128). Similarly, all of the above data are squared, all of them are added, and the sum is set to the second sum of squares (= current sum of squares 2) of all current data (step S129). Next, this time total value 2 and this time square sum 2
Then, after calculating the current variance 2 (= value for checking the reliability of variance 1) (step S130), the process returns to the main routine of FIG.

Returning to the main routine of FIG. 2 again, this time variance 1 obtained in step S105 and step S1
It is checked whether or not the current variance 2 obtained in 14 is equal (step S115). As a result of this check, if the two are equal, after resetting the counter A (step S116), the process proceeds to step S108 to check whether the variance 1 is equal to or larger than the threshold 1. However, if the result of the check in step S115 is that they are not equal,
Reset signal output terminal 29a to cancel dispersion 1
By outputting a reset signal from the microcomputer 29,
Is subjected to a hard reset (step S11).
7). As a result, even when an error occurs in the data or the variance 1 due to disturbance such as noise, it is possible to prevent a problem that control under inappropriate water discharge conditions based on the variance 1 having low reliability continues for a long time. .

A subroutine for driving a valve (not shown) in the opening / closing directions will be described with reference to FIGS.

First, when driving the valve in the opening direction, as shown in FIG. 6, both the transistors 21 and 23 are turned on and both the transistors 19 and 25 are turned off (step S131). When it is confirmed that 20 msec has elapsed (step S132), the transistor 2
The transistors 1 and 23 are turned off together with the transistors 19 and 25 (step S133), and the process returns to the main routine of FIG. Next, when the valve is driven in the closing direction, both the transistors 19 and 25 are turned on, as shown in FIG.
The transistors 21 and 23 are both turned off (step S134). When it is confirmed that 10 msec has elapsed (step S135), the transistors 19 and 25 are turned off together with the transistors 21 and 23 (step S136), and the process returns to the main routine of FIG.

Returning to the main routine of FIG. 2 again, it is finally checked in steps S101 and S102 whether or not 125 msec has elapsed since the processing for resetting and initial setting has been executed. The process returns to the start of the routine (Step S113). As a result, the processing of the main routine is executed at regular intervals.

Here, the reason why the above-described distributed calculation method according to the present embodiment requires a shorter calculation processing time than the conventional distributed calculation method will be described with a specific example.

For example, N data of 8 bits (= D
Assuming that the variance calculation is performed for (1) to D (N)), in the calculation method according to the related art, the total value of all data (= D (1) + D (2) +... + D (N−1)) + D
The process of obtaining (N)) and the process of obtaining the sum of squares of the data are indispensable. Therefore, if the time required for these arithmetic processes is represented by the number of instructions executed for addition and subtraction, the calculation of the total value is N-1 times (to add N data). In addition, in the calculation of the sum of squares, 8N times (the number of data bits is 8, so a maximum of eight additions are required for each square. The number of data is N, which is 8N), and N-1. Times (to add N data). Therefore, the addition and subtraction must be performed 10N-2 times in total. Therefore, the calculation method according to the related art has a problem that as the value of N increases (that is, as the number of data increases), the calculation processing time increases in proportion to the increase.

However, in the variance calculation method according to the present embodiment, as described in the flowchart of FIG. 4, the oldest data is subtracted from the previous total value and the latest data is added, and the current total value is calculated. At the same time, the sum of squares is subtracted from the previous sum of squares and the latest data is summed to obtain the current sum of squares. Therefore, the above 8
In the case of N-bit data, when the time required for the arithmetic processing is represented by the number of executed instructions for addition and subtraction, the total value is calculated twice (addition and subtraction), and the sum of squares is calculated 16 times (the oldest data and the latest data). For data, the sum is 8 × 2 = 16 at maximum and twice (addition, subtraction). Therefore, a total of 20 additions / subtractions may be performed, and the number of additions / subtractions does not increase even if the number of data (= N) increases. That is, assuming that the total number of data is 8, the conventional calculation method uses 1
In contrast to 0 × 8−2 = 78, the calculation method according to the present embodiment is the same as 20 times, and the time required for the arithmetic processing is about ４. This effect of reducing the processing time becomes more remarkable as the number N of data increases.

As described above, according to one embodiment of the present invention, every time the main routine of FIG. 2 is executed, the current total value 1 and the square sum 1 are calculated from the previously calculated total value and the square sum. Since the current variance 1 is obtained from the total value 1 and the sum of squares 1, the time required for the arithmetic processing can be reduced regardless of the number of data. Also, every 60 seconds, the reliability of the current variance 1 obtained by a simple calculation method is calculated using the variance 2 obtained by a normal calculation method.
And if variance 1 does not match variance 2,
Dispersion 1 is to be canceled. Therefore, an error occurs in data or dispersion 1 due to disturbance such as noise, and even if water is discharged due to a malfunction caused by the error data or the like, water is stopped after 60 seconds.

It should be noted that the above-mentioned contents relate only to each embodiment of the present invention and its modifications, and needless to say that the present invention is not limited to only the above-described contents.

[0060]

As described above, according to the present invention,
By reducing the complicated arithmetic processing as much as possible, it is possible to prevent the control from being hindered even when a microcomputer having a relatively low processing capability is used.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a circuit configuration of a water control device according to an embodiment of the present invention.

FIG. 2 is a flowchart showing a control operation of each part of the water control device shown in FIG.

FIG. 3 is a flowchart showing a subroutine for driving a sensor for setting water discharge conditions.

FIG. 4 is a flowchart showing a simple dispersion calculation subroutine for setting water discharge conditions.

FIG. 5 is a flowchart showing a normal dispersion calculation subroutine for setting water discharge conditions.

FIG. 6 is a flowchart showing a subroutine for driving a valve in an opening direction.

FIG. 7 is a flowchart showing a subroutine for driving a valve in a closing direction.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Sensor part 3 Valve drive part 5, 6 Signal processing part 7 DC power supply 9 Light emitting element 11 Light receiving element 13 Sensor circuit 15, 19, 21, 23, 25 Transistor 17 Latching solenoid 27 H bridge circuit 29 Microcomputer (microcomputer) 31 Resonator 33 reset circuit

Claims (12)

[Claims] An object detection device that receives a reflected wave of a transmitted propagation wave and determines the presence / absence of an object based on the value of the reflected wave, wherein an arithmetic process based on a plurality of data indicating the level of the reflected wave is performed. An object detection device comprising: a simplified arithmetic processing unit that executes by using a result of an arithmetic processing performed last time. 2. The object detection apparatus according to claim 1, wherein the result of the arithmetic processing includes removing oldest data from all data obtained by sampling a signal indicating the level of the reflected wave in a previous time. And an object detection device obtained by statistical processing including addition of the latest data. 3. The object detection device according to claim 1, wherein the statistical processing includes a variance calculation performed based on a sum value operation of the plurality of sampled data and a square sum operation of each data. An object detection device comprising: 4. The object detection device according to claim 1, wherein the simplified calculation processing means uses a result of a previously performed calculation process to indicate a level of the reflected wave. An object detection device for calculating the variance of data. 5. The object detection device according to claim 1, wherein a plurality of times indicating a level of the reflected wave each time the simplified calculation processing by the simplified calculation processing unit is repeated a predetermined number of times. Standard operation processing to acquire all data, remove the oldest data from this data, add the latest data, calculate the total value of these data, and calculate the variance based on the sum of squares operation An object detection device, further comprising means. 6. The object detection device according to claim 1, wherein an arithmetic processing result by said simplified arithmetic processing means is different from an arithmetic processing result by said standard arithmetic processing means. ,
An object detection device further comprising invalidating means for invalidating a result of the arithmetic processing by the simplified arithmetic processing means. 7. A water control apparatus for receiving a reflected wave of a transmitted propagation wave and controlling water supply in accordance with a result of determining the presence or absence of an object based on the value of the reflected wave, wherein the level of the reflected wave is indicated. A water control device comprising a simplified arithmetic processing means for executing arithmetic processing based on a plurality of data by using a result of arithmetic processing performed last time. 8. The water control device according to claim 7, wherein the result of the arithmetic processing is the removal of the oldest data from all data obtained by sampling a signal indicating the level of the reflected wave in the previous time. And a water control device obtained by statistical processing including addition of the latest data. 9. The water control device according to claim 7, wherein the statistical processing includes performing a variance calculation performed based on a total value operation of the plurality of sampled data and a square sum operation of each data. A water control device comprising: 10. The water control device according to claim 7, wherein the simplified calculation processing means uses a result of a previously performed calculation process to indicate a plurality of levels of the reflected wave. A water control device, which calculates a distribution of data. 11. The water control device according to claim 7, wherein a plurality of times indicating the level of the reflected wave each time the simplified calculation processing by the simplified calculation processing means is repeated a predetermined number of times. Standard operation processing to acquire all data, remove the oldest data from this data, add the latest data, calculate the total value of these data, and calculate the variance based on the sum of squares operation A water control device, further comprising means. 12. The water control device according to claim 7, wherein a calculation result obtained by the simplified calculation processing means is different from a calculation processing result obtained by the standard calculation processing means. ,
The water control apparatus according to claim 1, further comprising invalidating means for invalidating a result of the arithmetic processing by the simplified arithmetic processing means.