CN103815912A - Real-time monitoring method for falling behaviors of old people living alone on basis of thermal infrared sensor array - Google Patents

Abstract

The invention provides a real-time monitoring method for falling behaviors of old people living alone on the basis of a thermal infrared sensor array, and belongs to the technical field of information. The method comprises the following steps of (1), acquiring real-time data of activity behaviors of old people living alone in an indoor environment by using a thermal infrared sensor data acquiring system; (2) performing mathematical modeling on the real-time position of the monitored old people living alone in the indoor environment; and (3) judging space positions pi and j(t) which are positioned in the step (2) by using a falling monitoring algorithm, and judging whether the monitored old people falls down or not. The real-time monitoring method has the advantages that by using the method, falling behaviors can be efficiently monitored in real time, individual privacies of the old people are effectively protected, the daily life of the old people is not disturbed, and all-weather blind-point-free monitoring can be performed on an objective area.

Description

Old solitary people based on thermal infrared sensor array is fallen down behavior method of real-time

Technical field

The invention belongs to areas of information technology, propose a kind of old solitary people based on the observation of thermal infrared sensor array and fall down behavior method of real-time.The method is specially adapted to the behavior of falling down Real-Time Monitoring solitary to empty nest and the endowment old man of mechanism, and system can be sent immediately warning after old man falls down.

Background technology

At present, at home and abroad old people falls down monitoring field, and most of old peoples fall down monitoring equipment and adopted wearable portable sensor, such as acceleration and angular-rate sensor, or more simply helps call button.But most old peoples are often unwilling wears with oneself sensor device miscellaneous.After old people falls down, the situation that health can not move or brain loses consciousness happens occasionally, and in this case, helps call button also can lose efficacy.The method that another monitoring old people falls down is to adopt traditional camera head monitor, and the behavior of falling down is identified fast.But the often invasion of privacy of traditional camera head monitor, especially, among the home environment of old solitary people, is tended to bring psychological discomfort by the long-term supervision of photographic head.

Thermal infrared sensor is called again infrared motion sensor, higher to personage's body temperature sensitivity, and the sensor array being made up of this sensor can gather action/behavioural information of mobile personage, provides data basis to behavior analysis and Deviant Behavior monitoring etc.But the defect of thermal infrared sensor array is: the data precision of collection is low, only for reacting 0,1 two-value data of action severe degree.

Summary of the invention

In order to overcome portable sensor and traditional camera device is fallen down the deficiency in monitoring old people, the thermal infrared sensor technology that the inventive method adopts and old people fall down monitoring algorithm can by monitoring equipment and monitoring method to user's daily life bother and the infringement degree of privacy drops to minimum; And method of the present invention is not affected by light power, by day or the light at night change and can not bring behavioral data error; Meanwhile, comprehensive each corner that is installed on indoor roof of sensor array, can realize without blind monitoring.

The technical solution used in the present invention is as follows:

Old solitary people based on thermal infrared sensor array is fallen down behavior method of real-time and is comprised the steps:

Step 1: adopt thermal infrared sensor data collecting system to carry out real-time data acquisition to the crawler behavior of indoor old solitary people;

Described thermal infrared sensor data collecting system comprises controller module, thermal infrared sensor array and PC industrial computer; Multiple thermal infrared sensors are arranged and are formed top view video camera array at indoor roof, for taking the crawler behavior real time data in monitor area; Controller module comprises MCU singlechip microprocessor, USB transducer and multiple RS-422 transceiver; Multiple thermal infrared sensors form a thermal infrared sensor bus by serial or parallel connection, and every thermal infrared sensor bus is connected with MCU singlechip microprocessor by a RS-422 transceiver; PC industrial computer contains falls down monitoring algorithm, it is connected with MCU singlechip microprocessor by USB transducer, PC industrial computer sends and starts or stops instruction to MCU singlechip microprocessor, and receives and store the crawler behavior real time data being transmitted by MCU singlechip microprocessor;

Step 2: the old solitary people that step 1 is monitored carries out mathematical modeling at its indoor real time position of living in;

With expression formula s _ij(t), (i=1,, m, j=1, n) be illustrated in sensor active state 0 or the 1(0 that the t moment is positioned at (i, j) position and represent the non-active state of sensor, 1 represents sensor active state), when sample frequency is set to H, definition t(t>H/2) pixel value of moment institute's position location pixel is:

$p_{i,j}\left(t\right)=\frac{1}{H+1}\underset{u=t-H/2}{\overset{t+H/2}{\mathrm{\Σ}}}{s}_{i,j}\left(u\right)---\left(1\right)$

P _i,j(t) ∈ [0,1]; Suppose that the t moment has N(N≤m*n) the individual sensor that enlivens, position is by (i, j) expression, and making its pixel value is p _ij, utilize calculated with weighted average method to go out the t moment and old solitary people is determined to bit position be:

$(x_t,y_t)=\frac{{\mathrm{\Σ}}_{i=1}^m{\mathrm{\Σ}}_{j=1}^n(i,j)p_{i,j}\left(t\right)}{{\mathrm{\Σ}}_{i=1}^m{\mathrm{\Σ}}_{j=1}^n{p}_{i,j}\left(t\right)}---\left(2\right)$

The time series P of pixel value vector _t={ p ₍₁₎, p ₍₂₎..., p _(t), p _(t)=(p _1,1(t) ..., p _m,n(t)), the pixel value of current time vector p _(t)about pixel value vector time series P _tsingular value be defined as:

s _t＝||p _(t)-c|| （3），

C is cluster centre, and its expression formula is

|| || be Euclidean distance;

Step 3: utilize and fall down the locus p that monitoring algorithm is located step 2 _i,j(t) judge, judge that whether supervision personage state is as falling down, it specifically comprises following sub-step:

Step 3.1: adopt with acc power halter strap tolerance pixel value vector p _(t)about pixel value vector time series P _thalter strap value, it is defined as

$M_n^{\left(\mathrm{\ϵ}\right)}=\underset{t=1}{\overset{n}{\mathrm{\Π}}}\left(\mathrm{\ϵ}{\hat{q}}_t^{\mathrm{\ϵ}-1}\right)---\left(4\right),$

ε ∈ [0,1],

value by

value function calculates:

${\hat{q}}_t\left(\right\{p\left(1\right),p\left(2\right),...,p\left(t\right)\},{\mathrm{\θ}}_t)=\frac{\#\{r:s_r>s_t\}+{\mathrm{\θ}}_t\#\{r:s_r=s_t\}}{t}---\left(5\right),$

In formula (5), #{r:s _r> s _trepresent to work as s _r> s _ttime r counting; s _rfor at moment r according to the measured singular value of formula (3), r=1,2 ... t; θ _tevenly randomly drawed by interval [0,1] at moment t; Initial halter strap value is set as

ε is set as the value in [0.9,1];

Step 3.2: establish H ₀represent not fall down generation, and establish H ₁represent to fall down generation, λ is default detection threshold threshold value,, when

time, represent not fall down generation, falling down monitoring algorithm program Output rusults is H ₀, then re-execute step 3.2;

When

time, fall down monitoring algorithm programmed decision for falling down generation, program Output rusults is H ₁, fall down monitoring algorithm and make PC industrial computer record and store this Output rusults data, then establish

re-execute step 3.2, and then the old solitary people of realizing based on thermal infrared sensor array is fallen down behavior method of real-time.

The invention has the beneficial effects as follows: the method, when the behavior of falling down is carried out to real-time high-efficiency monitoring, has effectively been protected individual privacy, and to daily life without bothering, can carry out the round-the-clock monitoring without blind spot to target area.

Accompanying drawing explanation

Fig. 1 is thermal infrared sensor behavioral data acquisition system topological structure of the present invention;

Fig. 2 is the circuit theory diagrams of the thermal infrared sensor module in thermal infrared sensor behavioral data acquisition system of the present invention;

Fig. 3 is the circuit theory diagrams of the controller module in thermal infrared sensor behavioral data acquisition system of the present invention;

Fig. 4 is the design sketch of personage location under the top view camera application of thermal infrared sensor array of the present invention (4*5 divide plant).

The specific embodiment

The old solitary people that the present invention is based on thermal infrared sensor array is fallen down behavior method of real-time and is divided into two steps: the design of thermal infrared sensor behavioral data acquisition system, design and the realization of the behavior of the falling down real time monitoring algorithm based on behavioral data.

Step 1: the design of thermal infrared sensor behavioral data acquisition system

1.1) behavioral data acquisition system can be expanded maximum 128 thermal infrared sensors, and is installed on indoor roof.Fig. 1 shows the topological structure of thermal infrared sensor array, has 8 interface area (being drawn by controller) and has formed bus network.Wherein, the sensor with T is the end sensor in network.Bus also can branch, as shown in the part of Fig. 1 lower left.Each interface area can extend to 16 sensor nodes, therefore in sensor topology network, can expand at most 128 sensor nodes, can fully meet the mounting arrangement in single room or apartment.

Request and the sensor assembly of controller (shown in Fig. 3) to sensor assembly (shown in Fig. 4) sent replying by packet of controller.Packet comprises only 8, and minimum 4 (the 0th to the 3rd) represent the address of each sensor assembly, can be arranged by thumb-acting switch.In the time human action being detected, the 4th will be set to 1.The 5th is the LED lamp indication on sensor node, is set to 1 when lamp is bright.The 7th is set to 0 conventionally, in the time that mistake appears in system, is set to 1.

1.2) Fig. 2 is the sensor assembly electronic-circuit diagram in the present invention, and passive heat infrared sensor is called again infrared motion sensor, the variations in temperature that the action of the human body different from ambient temperature or other object causes can be detected.In sensor assembly, adopt NaPiOn(AMN11111, SUNX) inductive probe.It comprises 16 camera lenses, is used for gathering the infrared ray that exposes to four quadrants in thermal infrared inductive probe surface.In the time that this installation of sensors is on the roof of high 2.5 meters, infrared detection scope can reach 7.42m*5.66m.

The sensor AMN11111 adopts Matsushita Electric Industries's infrared ray sensor, be that the title that Matsushita Electric Industries issued on January 1st, 2012 is the infrared ray sensor in the data of " the burnt electric type MP motion sensor NaPiOn of motion sensor ", this file name is: bltn_cn_mp.pdf; Referral web site is: http://device.panasonic.cn/ac/c/dl/catalog/index.jsp series_cd=1391 & part_no=AMN11111.

Infrared sensor AMN11111 controls outfan (Output or Out) according to body temperature, and in the time detecting that human body enters surveyed area, outfan is output as numeral 1, otherwise is output as numeral 0.The digital output end of described infrared sensor AMN11111 connects the A2 pin of microprocessor PIC16F84A, and as the 4th of 8 bit data transmission package.Low 4 (the 0th to the 3rd) of 8 bit data transmission package is the address information of each sensor assembly, connects B0, B1, B2, the B3 pin of microprocessor PIC16F84A, and by thumb-acting switch, DIP-SW sets.The 5th of 8 bit data transmission package is LED light video data, connects the B4 pin of microprocessor PIC16F84A.The 7th is generally 0, and system is set to 1 while there is mistake, connects other pin of microprocessor PIC16F84A.The 6th for retaining position.Low-power consumption transceiver MAX489 in accompanying drawing, is applicable to RS422 standard traffic, can carry out full duplex communication, has short-circuit current-limiting function, realizes data-transformation facility in native system, is connected between microprocessor PIC16F84A and bus RS422.6P4C(RJ14 is passed through in the transmission of last 8 bit data transmission package) standard interface completes.

1.3) Fig. 3 is the controller module electronic-circuit diagram in the present invention, and controller module comprises singlechip microprocessor MCU(PIC16F873), USB transducer (ELECOMUC-SGT) and adopt eight transceivers of RS-422 communication standard.

(address is indicated by low 4 of 8 bit data transmission package for the data of each sensor assembly, behavioral data is indicated by the 4th) send to after controller module, microprocessor PIC16F873 extracts and arranges behavior two-value data, its implementation is: the RB0 to RB7 on microprocessor PIC16F873 amounts to 8 pins and connects respectively a 6P4C(RJ14) standard interface, each standard interface can connect maximum 16 sensor nodes (4 thumb-acting switch: can set 2 ⁴individual sensor node address), amount to maximum and can connect 128 sensor nodes.Finally, two-value behavioral data and sensor node address information are delivered to computer and are shown by serial communication by USB transducer (ELECOMUC-SGT).Finally, according to actual needs, such as factors such as room-size, design and develop out some sensor assemblies and a controller module, according to the topological structure composition behavioral data acquisition system shown in Fig. 1.

Step 2: the design of the behavior of falling down real time monitoring algorithm and realization based on behavioral data

The data precision gathering due to thermal infrared sensor array is low, only for reacting 0,1 two-value data of action severe degree.Therefore, the present invention has applied the top view camcorder method of roof sensor array, and two- value data 0,1 is converted into the continuous data on interval [0,1], has improved the gray level of pixel (sensing station).Meanwhile, of the present inventionly fall down behavior monitoring algorithm and improved the resolution of monitored area.

Core algorithm of the present invention-fall down behavior monitoring algorithm is as follows:

With expression formula s _ij(t), (i=1 ..., m, j=1 ..., n) be illustrated in the sensor active state (0 or 1) that the t moment is positioned at (i, j) position.When sample frequency is set to H (Hz), the pixel value of definition t (t>H/2) this pixel of moment:

$p_{i,j}\left(t\right)=\frac{1}{H+1}\underset{u=t-H/2}{\overset{t+H/2}{\mathrm{\Σ}}}{s}_{i,j}\left(u\right)---\left(1\right)$

p _i,j(t)∈[0,1]。Suppose that the t moment has N(N≤m*n) the individual sensor that enlivens, position is by (i, j) expression, and making its pixel value is p _ij, utilize weighted mean method at moment t, personage to be located:

$(x_t,y_t)=\frac{{\mathrm{\Σ}}_{i=1}^m{\mathrm{\Σ}}_{j=1}^n(i,j)p_{i,j}\left(t\right)}{{\mathrm{\Σ}}_{i=1}^m{\mathrm{\Σ}}_{j=1}^n{p}_{i,j}\left(t\right)}---\left(2\right)$

Effect after personage being positioned by formula (1) and (2) as shown in Figure 4, in the indoor environment of room layout shown in Fig. 4 upper left corner, behavior sequence: walk, clear up desk, be sitting on sofa, see TV, withdraw from a room etc. and to carry out successively, view data of selection in every 2 seconds within amounting to 20 seconds (top view picture: t=0 ... t=9).The bright dark degree of each pixel (being the square-shaped frame in every image) represents its pixel value size (in [0,1] interval, being obtained by formula (1) calculating).White circular cast in every image represents the position t moment experimenter (obtaining according to the pixel value of each pixel and formula (2) calculating) estimating.

The time series P of pixel value vector _t={ p ₍₁₎, p ₍₂₎..., p _(t), p _(t)=(p _1,1(t) ..., p _m,n(t)), the pixel value of current time vector p _(t)about pixel value vector time series P _tsingular value be defined as

s _t＝||p _(t)-c|| （3）

C is cluster centre, obtains it be expressed as by averaging method

|| || be Euclidean distance, Euclidean distance has embodied current time pixel value vector p _(t)and the diversity between the cluster centre c of pixel value vector time series.

The present invention adopts with acc power halter strap (randomized power martingale) tolerance pixel value vector p _(t)about pixel value vector time series P _thalter strap value, it is defined as

$M_n^{\left(\mathrm{\ϵ}\right)}=\underset{t=1}{\overset{n}{\mathrm{\Π}}}\left(\mathrm{\ϵ}{\hat{q}}_t^{\mathrm{\ϵ}-1}\right)---\left(4\right),$

ε ∈ [0,1],

value by

value function calculates:

${\hat{q}}_t\left(\right\{p\left(1\right),p\left(2\right),...,p\left(t\right)\},{\mathrm{\θ}}_t)=\frac{\#\{r:s_r>s_t\}+{\mathrm{\θ}}_t\#\{r:s_r=s_t\}}{t}---\left(5\right)$

In formula (5), #{r:s _r> s _trepresent to work as s _r> s _ttime r counting.S _rfor at moment r according to the measured singular value of formula (3), r=1,2 ... t.θ _tevenly randomly drawed by interval [0,1] at moment t.Initial halter strap value is set as

ε is set as the value in [0.9,1].

Falling down with halter strap framework in the process of monitoring, after a new data sample (the pixel value vector of moment t) is acquired, adopts testing of hypothesis differentiation to fall down behavior and whether occur: H ₀there is not H for not falling down ₁for falling down generation.Meet

$0<M_n^{\left(\mathrm{\&epsiv;}\right)}<\mathrm{\&lambda;}---\left(6\right)$

Time, halter strap detects and will continue to carry out.Wherein, λ is the detection threshold threshold value that user sets.When time, suppose H ₀be rejected, abnormal (falling down behavior) is monitored to, and halter strap detects and restarts:

Due to { M _n: 0 < n < ∞ } be non-negative halter strap value, and E (M _n)=E (M ₀)=1, according to Du's cloth halter strap space maximal inequality (Doob ' s maximal inequality), has

$P(\underset{k\&le;n}{\max }{M}_k\&GreaterEqual;\mathrm{\&lambda;})\&le;\frac{1}{\mathrm{\&lambda;}},\mathrm{\&lambda;}>0,n\&Element;N---\left(7\right)$

Its meaning is, for any halter strap value M _k, the probability with higher value is very little, when halter strap value is greater than λ, and H ₀be rejected.Falling down in monitoring, when in the situation that the behavior of not falling down occurs, inequality (7) is that false alarm rate (False Alarm Rate, FAR) provides the upper bound.

The monitoring algorithm of falling down of the present invention, halter strap detects (Martingale Test, MT), and false code is as follows:

Initialize: M (0)=1; T=1; P _t={ }.

Set: λ.

1: enter circulation loop

2: the pixel value vector P (t) obtaining at moment t.

3: if P _t={ }:

4: the singular value P (t) that sets P (t) :=0.

5: otherwise:

6: calculate P _tin the singular value of each sample and P (t).

7: calculate

value

(formula 5).

8: calculate M (t) (formula 4).

9: if M (t) > is λ:

10: monitor the behavior of falling down, system alarm indication.

11: make M (t)=1.

12: reinitialize P _t={ }.

13: otherwise:

14: add P (t) to time series P _t.

15: make loyal t:=t+1. of time

18: finish epicycle circulation loop.

Claims (1)

1. the old solitary people based on thermal infrared sensor array is fallen down behavior method of real-time, it is characterized in that, the method comprises the steps:

Step 1: adopt thermal infrared sensor data collecting system to carry out real-time data acquisition to the crawler behavior of indoor old solitary people;

Described thermal infrared sensor data collecting system comprises controller module, thermal infrared sensor array and PC industrial computer; Multiple thermal infrared sensors are arranged and are formed top view video camera array at indoor roof, for taking the crawler behavior real time data in monitor area; Controller module comprises MCU singlechip microprocessor, USB transducer and multiple RS-422 transceiver; Multiple thermal infrared sensors form a thermal infrared sensor bus by serial or parallel connection, and every thermal infrared sensor bus is connected with MCU singlechip microprocessor by a RS-422 transceiver; PC industrial computer contains falls down monitoring algorithm, it is connected with MCU singlechip microprocessor by USB transducer, PC industrial computer sends and starts or stops instruction to MCU singlechip microprocessor, and receives and store the crawler behavior real time data being transmitted by MCU singlechip microprocessor;

Step 2: the old solitary people that step 1 is monitored carries out mathematical modeling at its indoor real time position of living in;

With expression formula s _ij(t), (i=1,, m, j=1, n) be illustrated in sensor active state 0 or the 1(0 that the t moment is positioned at (i, j) position and represent the non-active state of sensor, 1 represents sensor active state), when sample frequency is set to H, definition t(t>H/2) pixel value of moment institute's position location pixel is:

$p_{i,j}\left(t\right)=\frac{1}{H+1}\underset{u=t-H/2}{\overset{t+H/2}{\mathrm{\&Sigma;}}}{s}_{i,j}\left(u\right)---\left(1\right)$

P _i,j(t) ∈ [0,1]; Suppose that the t moment has N(N≤m*n) the individual sensor that enlivens, position is by (i, j) expression, and making its pixel value is p _ij, utilize calculated with weighted average method to go out the t moment and old solitary people is determined to bit position be:

$(x_t,y_t)=\frac{{\mathrm{\&Sigma;}}_{i=1}^m{\mathrm{\&Sigma;}}_{j=1}^n(i,j)p_{i,j}\left(t\right)}{{\mathrm{\&Sigma;}}_{i=1}^m{\mathrm{\&Sigma;}}_{j=1}^n{p}_{i,j}\left(t\right)}---\left(2\right)$

The time series P of pixel value vector _t={ p ₍₁₎, p ₍₂₎..., p _(t), p _(t)=(p _1,1(t) ..., p _m,n(t)), the pixel value of current time vector p _(t)about pixel value vector time series P _tsingular value be defined as:

s _t＝||p _(t)-c|| （3），

C is cluster centre, and its expression formula is

|| || be Euclidean distance;

Step 3: utilize and fall down the locus p that monitoring algorithm is located step 2 _i,j(t) judge, judge that whether supervision personage state is as falling down, it specifically comprises following sub-step:

Step 3.1: adopt with acc power halter strap tolerance pixel value vector p _(t)about pixel value vector time series P _thalter strap value, it is defined as

$M_n^{\left(\mathrm{\&epsiv;}\right)}=\underset{t=1}{\overset{n}{\mathrm{\&Pi;}}}\left(\mathrm{\&epsiv;}{\hat{q}}_t^{\mathrm{\&epsiv;}-1}\right)---\left(4\right),$

ε ∈ [0,1],

value by value function calculates:

${\hat{q}}_t\left(\right\{p\left(1\right),p\left(2\right),...,p\left(t\right)\},{\mathrm{\&theta;}}_t)=\frac{\#\{r:s_r>s_t\}+{\mathrm{\&theta;}}_t\#\{r:s_r=s_t\}}{t}---\left(5\right),$

In formula (5), #{r:s _r> s _trepresent to work as s _r> s _ttime r counting; s _rfor at moment r according to the measured singular value of formula (3), r=1,2 ... t; θ _tevenly randomly drawed by interval [0,1] at moment t; Initial halter strap value is set as ε is set as the value in [0.9,1];

Step 3.2: establish H ₀represent not fall down generation, and establish H ₁represent to fall down generation, λ is default detection threshold threshold value,, when

time, represent not fall down generation, falling down monitoring algorithm program Output rusults is H ₀, then re-execute step 3.2;

When

time, fall down monitoring algorithm programmed decision for falling down generation, program Output rusults is H ₁, fall down monitoring algorithm and make PC industrial computer record and store this Output rusults data, then establish re-execute step 3.2, and then the old solitary people of realizing based on thermal infrared sensor array is fallen down behavior method of real-time.

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