GB2348725A

GB2348725A - Device for monitoring a person in their home

Info

Publication number: GB2348725A
Application number: GB9907782A
Authority: GB
Inventors: Kevin Doughty
Original assignee: Individual
Current assignee: Individual
Priority date: 1999-04-07
Filing date: 1999-04-07
Publication date: 2000-10-11
Also published as: GB9907782D0

Abstract

The challenge of maintaining a person's independence in the community is difficult when that person suffers from confusion or the early stages of dementia. The risk of accident of accident becomes very high due to the loss of cognitive function and ability to recognise dangers. This risk may be further increased if the individual tends to wander outside the home during the hours of darkness when there will be few people about to provide help. It is therefore necessary to advise confused people not to go out at night and, if they do go out, inform the relevant authorities or carers so that they can be brought back home. The present invention is an integrated and intelligent device based on sensors which is installed in the home rather than on the person. Consequently, it is not related to the electronic tags employed to restrict the movements of prisoners who have released from jail prematurely. This device comprises a plurality of sensors to detect movement close to the exit door. According to the sequence of detection by the sensors and to the time of day or other programmed parameters, the device provides reminders that the person should not go out. If they do go out then this is action is also detected by the sensors and, when appropriate, is used to inform carers. The device is particularly suited to application with a community alarm telephone system.

Description

A MULTI-SENSOR INTEGRATED DEVICE FOR THE DETECTION AND PREVENTION OF WANDERING BEHAVIOUR BY CONFUSE INDIVIDUALS Background to the Invention Senile dementias such as Alzheimer's Disease affect large numbers of older people ; perhaps 20% of those aged over 80 years may suffer to a greater or lesser degree."Care in the Community"legislation, and the closing of many geriatric hospitals and institutions which care for those with mental illness, have encourage the independence of older people by enabling them to remain in their own homes. This is possible through the support of various agencés and has allowed many confuse elders to avoid the trauma of having to give up their homes for their final years of life.

Unfortunately, many dementia sufferers, and many other confuse people suffering from physical illnesses such as diabetes, live alone. Consequently, there may be no informa carer, such as a family member, available to provide them with timely rerninders and guidance on maners of behaviour and need when their cognitive functions become impaire. The result is that they are at risk of accident inside and outside their homes. Indeed, there is a real danger of them becoming lost when left to wander outside their homes. During the day-time, help may be available and there will be drop-in centres for them to attend. However, at night, they may be left to wander aimlessly for many hours and, under inclement weather conditions, or if not properly dresse, they may suffer from exposure and die.

It may be apparent that the risks associated with this behaviour need to be managed either by providing appropriate advice to the individual or by alerting an appropriate authority of any and every incidence of nocturnal wandering.

Several different devices have been propose to deal with such behaviour. They all tend to be based on some worn device or tag which is attache to the person being monitored. In one example, the worn device is essentially an unpowered coil with some miniature coding circuitry. This coil interacts with a larger active coil in an external door frame whenever the Derson passes over the threshold. This action is detected by electronic circuitry connecte to ttie larger coil which signals an alert through some mechanism. In other examples, the person wears an active transmitter which provides an occasional coded identification signal. This is received by a second device in the home provided that the tag is within a certain range. If this signal is not received for a certain period then either the transmitter has been removed or the wearer has moved out of range i. e. they have left home.

The devices and systems described above are similar to the electronic tagging methods employed to detect when prisoners, who have been released early from prison under curfew conditions, have left home. Indeed, every system that has been propose for the tagging of prisoners has also been considered for monitoring the movements of dementia sufferers. It may be apparent that this comparison between dementia sufferers and prisoners is unpopular both with older people and with their carers.

The present invention relates to a reminder and alarm device for use by confuse people. It does not require thc person who is at risk of wandering to be tagged in any way.

Description of the Invention A number of electronic devices have appeared on the market in recent years for app, ication in intruder alarms. These include door opening sensors, passive and active infra-red movement sensors, ultrasonic and microwave movement sensors, pressure pads, and a number of other devices which detect the effects of opening a door or window through pressure change sensors or infra-sonic sensors. These are all single-stage devices which have little local intelligence and which provide an alarm signal whenever a person is detected.

In principle, it may be possible to employ such devices to monitor the activity or movement of a person within the home environment. Indeed, such devices have been used for a number of years to detect the lack of mobility and movement associated with a person who has become unwell. They require a decision processor to be placed with the receiver (normally a personal emergency telephone) to interpret the lack of activity as a genuine alarm condition.

More recently, the outputs of a number of such devices have been combine in order to derive an overall activity index which is analyse remotely. This analysis can be performed with a computer in the home (see, for example, Doughty, King, Williams and Wood "DIANA-Dementia Information and Needs Analyser",-Proceedings of the IEEE Engineering in Medicine and Biology Conference, Hong Kong, 31 Oct.-2nd. November, 1998) or by using the telephone network facilities.

Though the total activity index may provide an overall estimate of a peson's life-style, it does not necessarily indicate fundamental problems of cognitive function. However, the sequence of operation of an array of sensors will provide unambiguous information on the behaviour of a person both inside and on entering the home environment. For example, consider the situation where 3 sensors, A, B, and C, are employed in the vicinity of an external door. Sensor A might monitor movements and activity within the lobby or hallway.

Sensor B may monitor the state of opening and closing of the door while sensor C monitors movements outside the door. If a person leaves the remises then their actions would be detected by the three sensors in turn A, B and C. Similarly, a person arriving at and entering the property from outside would be detected by a sequence C, B and A.

Extending the above idea, a visitor who arrives at the property and is greeted by the occuper would produce a sequence C, A, B, A if they are admitted into the property, but C, A, B, C, A if they do not enter but then leave. Similarly, if they are joined outside by the resident then the sequence of triggering will be C, A, B, C. It may thus be evident that a combination of such sensors may be employed to determine unambiguously whether a resident has left home or remains inside.

Figure I shows an arrangement of sensors as described above where A, B and C are independent sensors, D is a decision processor, E is a real-time clock and F is another programme input (perhaps a simple switch) which may be operated manually or using some wireless link. G and H are output devices. Using the arrangement shown in Figure 1, the decision processor, D, may be programme to detect any sequence of sensor activations and to produce an output through G or H depending on the settings of the switch F and/or the time of day measured using clock E. An output may be sent to G or to H according to the programme parameters. For example, G may be a speaker which is capable of playing an audio message as soon as a particular sequence is detected. If perhaps two sensors such as A and B have been triggered and the real-time clock shows that it is the middle of the night then G may play a message such as"Please don't go out, it's cold and dark". This message might also be a simple audio alarm such as a buzzer or a siren or it might be shown as a text message on a large television or LED, LCD or moving matrix display. It might similarly be in the form of a fixed message display which becomes illuminated either permanently or in a flashing form when appropriate.

Many developed countries such as Grenat Britain contain an interesting mix of ethnic communities. It is inevitable that English will not be the first langage of many of this people, especially those who were brought up in other countries or those who have always spoken a first langage other than English. These include immigrants from Africa and from the Indian sub-continent but also many from the indigenous population who speak Welsh of Gaelic fluently often at the expense of Welsh. For such people, it is essential that the messages that are presented are in their preferred langage.

If this message is subsequently ignored and the person then leaves the building as detected by an external sensor C or by the lack of indoor activity detected by A then H may be used to provide an alarm either immediately or later, if the person hasn't returned within a specified period. This alann may be in the form of a direct wired link to a carer (such as a warden in sheltered housing) or, in our preferred arrangement, as a radio transmission to a personal emergency telephone which can relay this alert directly to a community response centre or to a relative.

It follows that under certain circumstances, especially when small apartments are being considered, only 2 independent sensor inputs may be necessary to determine whether a person has left the remises. However, for bigger dwellings, and especially those with multiple external doors, more independent sensor inputs may be required to reach the same conclusion. In each case, the arrangement of sensors, clock, switches and outputs may be integrated into a single device by direct wiring. This device may be mounted in an appropriate location such as by the main exit door as a quickly installe retrofit.

In practice, the device may be switched on by a carer at night after preparing a person for bed or it might be switched on automatically when another sensor detects darkness or simply when the time is appropriate e. g. after 9pm. It may then be disarmed by a carer in the morning or automatically in some way when appropriate. The carer might similarly select the parameters that are relevant to a particular situation and programme them into the device using an intelligent hand-set.

If one of the independent sensors monitors the state of the exit door then the same device may be used to provide reminders to the resident that the door should be closed. The same information might also be relayed to the carers if appropriate using the communications links described above.

In some cases, the person who is considered to be at risk may be wearing some other sensor systems to automatically detect falls or other social problems. These devices may contain radio transmitter or radio beacon circuitry which would help police or paramedics to find them in case of emergency. Such equipment might be operated remotely by the propose device using one of its outputs labelle H in Figure 1. For example, a licence exempt radio transmitter operating in the VHF or UHF range would have a line-of-sight range of 50 metres which would enable it to communicate with such a device after the person had left the home environment. This would help locate them if they hadn't retumed within a certain period of time.

Claims

Claims 1. An integrated and dedicated electronic social care device for supporting a confuse person in their own home, and employing some or all of the. following elements :

2 or more independent sensors which provide détection of mouvement about an exit door, a real-time clock, a programmable decision processor, an output device or devices.
2. A device as described in 1. in which the independent sensors may be contact switches, passive infra-red movement dctectors, vibration detectors, pressure mats, active infra-red or microwave devices, ultrasonic movement sensors, infra-sonic sensors, pressure change sensors or inductive sensors.
3. A device as described in 1. which may be activated into a"stand-by"mode by the activation of any individual sensor.
4. A device as described in 1. which may determine the nature of an activity from the sequence of activations of the input sensors.
5. A device as described in 1. which may automatically provide a response which is dependent on the sequence of activation of input sensors.
6. A device as described in previous claims which may provide a wading to a person who is about to leave home.
7. A device as described in previous claims where the warning may be in the form of a audio message or alarm.
8. A device as described in previous claims where the warning message may be repeated until a sequence of activities is followed.
9. A device as described in previous claims where the warning message may be in the form of a visible display of any sort.
10. A device as described in previous claims where warning messages may be in any selected and appropriate langage.
11. A device as described in previous claims which may be used to automatically detect a person leaving their home.
12. A device as described in previous claims which may raise an alarm only during certain times which may be considered to be inappropriate.
13. A device as described in previous claims where inappropriate hours may be programme by carers according to an individual's risk or habits.
14. A device as described in previous claims which may initiate an alert when a person leaves home.
15. A device as described in previous claims which may initiate an alert after a specified delay when a person leaves home.
16. A device as described in previous claims which may initiate an alert only if the person leaves home and doesn't rectum within a specified time.
17. A device as described in previous claims which may be provided with a direct wired link to provide an alarm message to a carer.
18. A device as described in previous claims where an alarm is signalled by an audio alert such as a siren or bell.
19. A device as described in previous claims where the alarm is transmitted through a dedicated intercom system.
20. A device as described in previous claims where the alarm is transmitted using a radio module.
21. A device as described in previous claims which is compatible with a social or community alarm system.
22. A device as described in previous claims where a mobile carer may be alerted directly.
23. A device as described in previous claims which may automatically switch on other equipment that may be worn by the person or which may be carried by the person in the forum of a pager, a mobile phone or other sensors.
24. A device as described in any of the previous claims which can remind a person that they have le$ the door open.
25. A device as described in any of the previous claims which can wam a carer or a control centre or a warden that a door has been left open.