Technical Field
The present invention relates to a remotely located device which is capable of
autonomously monitoring defined parameters in its environment, and automaticall5 y
responding to local changes and stimuli requiring real-time reaction while
simultaneously triggering an alert and feeding signals to one or more distant monitoring
stations. The device functions as a “virtual presence” of the distant monitoring stations
at the remote location.
10
Background
Several modern day infrastructural facilities require delivery of services across a large
geographic area covering a town, city or district. Well known examples of such facilities
include lighting infrastructure (including lighting of roads and streets), law and order
15 functions, traffic management, public transport and communication. In the present
form, many of these functions require physical presence of human agents to either
perform surveillance or monitor effectiveness of service delivery. With the swift spread
of urbanization and rapidly growing urban populations it is becoming increasingly
difficult to provide such services effectively. Increasing social problems as well as rising
20 expectations are also causing citizens of such communities to demand additional and
more effective services. In particular, issues relating to women’s security and general
street crime, as well as health concerns arising from escalating levels of pollution are
fuelling demands for monitoring and control of several new parameters affecting quality
of life. Increasing globalization is also influencing urban society across the world and
25 driving futuristic developments in the form of “smart city” initiatives. Each of these
factors is driving a need for need for increase in efficiency and effectiveness of these
services that is an order of magnitude higher than what is available today. Existing
measures and methods, including those that are automated to an extent, are incapable
of meeting or adapting to these demands owing to the essentially passive nature of the
30 operation of these solutions.
3
An example of an existing solution is the use of CCTV networks to provide continuous
surveillance as a means to solve issues relating to women’s security and street crime.
Such a solution provides a very limited level of deterrence as it is incapable of
autonomous identification of a situation requiring an immediate action, nor is it capable
of responding to such a situation. It is impervious to the content it is observing an5 d
merely relays all content to its remote server. As a result it fails to provide any
immediate support in a fast developing local situation being entirely dependent on the
availability and alertness of human resources at the remote monitoring station (103).
Such an arrangement is also extremely inefficient and wasteful of resources, as only a
10 tiny fraction of its recording is ever utilized. Figure-1 shows the structure of a typical
modern CCTV system. Individual CCTV cameras [(101)(a) to (101)(n)] continuously feed
video streams to remote storage servers (102). The video stream occupies a wide
bandwidth in the communication medium connecting each CCTV camera [(101)(a) to
(101)(n)] to the storage servers (102). Practical considerations often require the CCTV
15 cameras (101) and the storage medium (102) to be considerably spaced apart. Wired
mediums are often unwieldy and/or expensive to deploy. Wireless media are therefore
more prevalent, but the video streaming requires significant amount of bandwidth
which limits the number of CCTV cameras which can share the common wireless
medium. The continuous video streaming also requires enormous storage capacity at
20 the storage servers (102), adding to cost and complexity. Besides being inefficient in
terms of unnecessary wireless transmission power consumption, the continuous storage
also wastes computing resources at the storage servers. The utilization of the stored
data is extremely low as it is accessed only under rare conditions, when investigations
are carried-out post-facto by human agencies much after the occurrence of an event
25 that often goes undetected when it actually occurs. This limitation greatly undermines
the effectiveness of this arrangement.
Existing arrangements of remote surveillance also suffer from the limitation of providing
a singular function. A CCTV system will only address general visual surveillance and will
30 be unable to monitor air quality at its location, for example. Separate air-quality
monitoring systems are needed at the same location, if required. The need for multiple
remote services therefore results in a multiplicity of overlapping networks with several
4
pieces of equipment being replicated for each system resulting in increased cost,
avoidable energy consumption and unnecessary space requirements. The multiplicity of
devices mounted in or around a single location also results in considerable clutter and
confusion. The independent monitoring systems are also unable to leverage expensive
resources such as communication channels that could easily be shared between them5 .
The growing needs for additional services create the constant need for installing newer
systems for independently fulfilling each new requirement thereby constantly
magnifying the problems of cost, energy consumptions and space requirements.
10 It is therefore necessary to develop a totally new architecture that is capable of
overcoming these limitations and providing a more effective, efficient and scalable
solution.
15 SUMMARY
This invention describes a device which overcomes the above-mentioned limitations.
The device comprises an intelligent monitoring unit that processes the data provided by
one or more sensor units and identifies conditions requiring action and/or reporting.
20 The intelligent monitoring unit autonomously responds to such conditions in a specified
manner by operating output units coupled to its outputs and reporting the occurrence
to one or more distant monitoring stations.
In a preferred embodiment at least one sensing unit is incorporated within the device.
25
In another embodiment the device processes data from audio-visual sensors such as
cameras to monitor its environment. It analyzes the video data in real-time and
identifies situations requiring a response and triggers appropriate actions. The actions
may include initiating a live video feed to a distant monitoring station.
30
In a preferred embodiment one or more audio-visual sensors, such as cameras, are
incorporated within the device.
5
Another embodiment comprises the device processing data from an Active RFID sensor
capable of receiving radio signals indicative of emergency situations such as from
Personal Emergency Units also known as Panic Alarms. The device may respond to the
emergency situation by driving lighting units and/or audio alarms to call attention to th5 e
emergency. At the same time, the device may transmit details of the emergency to a
distant central monitoring station.
In a preferred embodiment the Active RFID sensor is incorporated within the device.
10
The invention also relates to a method of providing automatic real-time responses to
monitored ambient parameters at one or more remote locations using sensors to
continuously monitor the desired ambient parameters, an intelligent monitoring unit to
process the signals from the sensors and identify situations requiring action, including
15 driving optional output units to provide a response locally, and using one or more
communication units to communicate the details of the situation to one or more distant
monitoring stations.
The device may optionally be networked with other similar devices to perform functions
20 collectively and provide a multiplier effect by enabling synergistic operations over a
larger geographic area.
The device is designed to provide several functions using a common set of sensors and
optional output units, in order to address many different situations in an integrated
25 manner. As a result, a single device is capable of performing the functions of several
traditional devices in an efficient and economical manner.
The autonomous monitoring device is also designed to be dynamically scalable in terms
of processing capability in order to adapt itself to changing ambient conditions. It is
30 therefore capable of implementing many functions simultaneously and can support
additional features to fulfill future requirements.
6
The device is also capable of being integrated with existing infrastructure electrical
elements such as street lights from which it can draw power and mechanical support
while, at the same time utilizing it as an output device for performing some of its
intended functions.
5
With the appropriate combination of sensors and output units, the device can operate
as a “virtual presence” device in the nature of functioning as the “eyes”, “ears” and
“nose” of several different user agencies, at its physical location. The device is capable of
being utilized as a resource for providing
10
BRIEF DESCRIPTION OF DRAWINGS:
The invention will now be explained with reference to the accompanying drawings in
15 which like characters represent like parts throughout the drawings
Fig. - 1 shows a CCTV Surveillance Network known in the art.
Fig. - 2 shows the basic block diagram of a preferred embodiment of a device in
20 accordance with the present invention.
Fig. - 3 shows the block diagram of one preferred embodiment of a device in
accordance with the present invention.
25 Fig. - 4 shows a block diagram of another preferred embodiment of a device in
accordance with the invention.
Fig. - 5 shows a block diagram of another preferred embodiment of a multifunction
device in accordance with the invention.
30
Fig. - 6 shows a block diagram of a preferred embodiment of the Processing unit of
a device in accordance with the invention.
7
DETAILED DESCRIPTION5 :
Fig. – 2 shows the basic structure of a device according to the invention. One or more
Sensing Units (201) detect or measure specific ambient parameters and provide data to
an Intelligent Monitoring Unit (202). Sensing Units (201) may be external to the device,
10 or may form part of it in preferred embodiments. The parameters being monitored are
defined by the applications for which the device is used. The Intelligent Monitoring Unit
(202) constantly analyzes the information regarding the various parameters, which is
provided by the Sensing Units (201) and determines the need for a suitable response
based on predefined criteria which characterize an “event”. One or more
15 communication units (204) coupled to the Intelligent Monitoring Unit (202) enable the
device to transmit data pertaining to the event to one or more distant monitoring
stations in real-time. The communication units (204) also enable the distant monitoring
stations to remotely configure the device operating parameters and/or update the
predefined criteria whenever needed. At the same time, one or more Output Units (203)
20 coupled to the outputs of the Intelligent Monitoring Unit (202) enable the device to
generate autonomous responses to events locally. It is also possible for the device to
execute desired actions at the device location under control of the distant monitoring
stations thereby enabling any combination of autonomous and remotely directed
actions. The arrangement furthermore offers the ability to trigger actions at the device
25 location from the remote monitoring stations independent of or in combination with,
the locally sensed conditions.
The following paragraphs describe preferred embodiments of the device according to
the invention. It will be obvious to a person of ordinary skill in the art will be aware that
30 the activities described are only exemplary and several variations are possible, all of
which are understood to fall within the scope of this disclosure. Various subsets of
8
activities described as well as obvious extensions of functions would be similarly covered
by this disclosure.
Fig. – 3 shows one preferred embodiment of the device. This embodiment is capable of
addressing 2 independent applications – one relating to personal emergency (5 such as
events relating to Women’s security, as well as situations involving a medical
emergency), and another to Tracking of Mobile Assets such as vehicles. The Input
Sensing Unit (201) incorporates an Active RFID unit (301) which provides continuous,
real-time monitoring for the emission of radio-frequency signals from a Personal
10 Emergency device that may be activated in its vicinity to indicate a personal emergency
requiring urgent response. The Intelligent Monitoring Unit (202) receiving the
information from the Active RFID Unit may be configured to provide an autonomous
immediate response to personal emergency events by activating Audio Alarm Unit (304)
and Lighting Control Unit (303) contained in Output Unit (203), to generate local alerts.
15 At the same time, the Intelligent Monitoring Unit (202) could also send out an alert to
the distant Monitoring Stations through Communication Unit (204) so as to initiate a
wider response. The device also incorporates Video Capture Unit (302) – such as one or
more Video Cameras – which may be activated simultaneously to provide a real-time
audio-video stream to the distant monitoring stations thereby enabling more effective
20 action by the distant monitoring stations and create a record of the emergency situation
for future use. This arrangement avoids the wasteful streaming and avoidable storage of
video data which is characteristic of conventional CCTV systems. It is also possible to
incorporate pre-event video data in a manner similar to conventional CCTV systems by
providing a local video buffer in the device and uploading the buffer contents to the
25 remote monitoring station on the detection of an event.
Active RFID unit (301) also monitors the emission of radio-frequency signals by mobile
assets, such as Public Transport Buses, Goods Transport Vehicles, Corporate employee
Transport vehicles, Taxis and even private vehicles equipped with such Active RFID tags.
30 On the other hand, Active RFID signals from within-range mobile assets would not
trigger such a response but would instead transmit identification details to the distant
monitoring stations through Communication Unit (204). Traffic management functions
9
could also be autonomously implemented by automatic identification of vehicular
access to unauthorized areas, etc. coupled with Video capture of the event for use as
evidence. The device may also be configured with the ability to automatically debit an
account associated with each mobile asset entering a “charged- access” area such as a
Tolled road by sending a local Active RFID transmission to the tag inside the vehi5 cle.
Fig. - 4 shows another preferred embodiment of the device in which the Output Unit
(203) includes one or more Audio-Visual Display units (401) in addition to the features
10 contained in the device according to Fig.-3. In this arrangement the device is capable of
receiving information through Communication Unit (204) from distant stations for
multimedia display at its location. Such information can include traffic instructions or
traffic advisories or other public announcements. The arrangement can also be utilized
to display advertisements for public viewing thereby creating a source of revenue for
15 agencies owning the device. The device according to this embodiment extends the
“virtual presence” of each of the distant monitoring stations involving one or more
different agencies, by enabling several sensory inputs to be “observed” from distant
locations while at the same time enabling audio-visual messages to be transferred to
each remote device location in real-time from each of said distant monitoring stations.
20
Fig. - 5 shows another preferred embodiment of the device which is capable of
implementing several diverse functions, including:
1) responding-to and triggering alerts in personal emergency situations (such as those
effecting women’s security);
25 2) furnishing vehicle tracking information;
3) enabling streamlining of traffic conditions;
4) improving energy efficiency of street lighting facilities; and
5) monitoring and reporting on air quality (pollution levels).
To provide these diverse functions, the Input unit (201) of the device incorporates Active
30 RFID unit (301), Video Capture unit (302), Ambient Light Sensing unit (501), Dust Particle
Sensing Unit (502), and Polluting Gas Sensing Unit (503). The Output Unit (203) of the
device includes Lighting Control unit (303), Audio Alarm unit (304) and Multimedia
10
Display Unit (401). The Intelligent Control Unit (202) incorporates Processing Unit (504),
Memory Unit (505), and Storage Unit (506).
Active-RFID unit (301) constantly listens for RFID transmissions originating either from
Personal Emergency devices activated by Personal Emergency situations or RFI5 D
transmissions originating from passing vehicles. Such “tagged” passing vehicles may
include public transport buses, goods transport vehicles, utility service vehicles (such as
garbage trucks and utility maintenance trucks), hired transport vehicles (such as taxis
and corporate employee transport vehicles) and even private vehicles. Individual
10 Identification numbers of each detected RFID Tag, whether corresponding to a Personal
Emergency device signaling an emergency event or the transmission from a passing
tagged vehicle, are provided to the Intelligent Monitoring Unit (202) for analysis and
necessary action.
15 Video Capture unit (302), collects ambient audio and video content and provides it to
the Intelligent Monitoring Unit (202) in real-time either in continuous mode or
selectively on the basis of control signals from the Intelligent Monitoring Unit (202). The
multimedia stream from the Video Capture Unit (302) is presented to the Processing
Unit (504) which performs compression and optional encryption while making use of
20 Memory Unit (505) in the process. The compression and/or encryption may be in
accordance with standard compression and encryption protocols. The resultant data is
then either stored in Storage Unit (506) or directly streamed out to one or more distant
stations, depending on dynamically configurable behavior. The video content stored in
Storage Unit (506) may also be streamed out to the distant stations when required. It is
25 also possible for the Processing Unit (504) to perform image analysis of the video
content for various purposes including identifying crime situations not involving Active
RFID based personal emergency triggers, number-plate recognition for automatic traffic
violation applications or searching for car theft vehicles.
30 Ambient Light Sensing Unit (501) provides data to Processing Unit (504) that may be
used to implement autonomous street lighting control and energy management of
street lighting at the remote location of the device.
11
Dust Particle Sensing Unit (502) and Polluting Gas Sensing Unit (503) collect data on local
pollution levels and enable Processing Unit (504) to collate such data with other local
parameters and convey the data to one or more distant monitoring centers either
periodically or in response to specific requests from such distant centers. Exemplary Ai5 r
Pollutant parameters are given below (however additional parameters may be detected
or measured):
a) Volumetric Concentration of Particulate Matter below 2.5 micron size. (PM2.5)
b) Volumetric Concentration of Particulate Matter below 10 micron size. (PM10)
10 c) Carbon-Monoxide (CO) concentration level.
d) Ozone (O3) concentration level.
e) Sulphur Dioxide concentration level.
Output Unit (203) includes Access Control Unit (507) which enables selective physical
15 access to controlled-access areas based on the result of the analysis of, for instance, the
Active RFID signals received and processed by Intelligent Monitoring Unit (202). The
selective access may alternatively be based on the result of the analysis of, the Video
Capture input received and processed by Intelligent Monitoring Unit (202).
20 Output Unit (203) further includes Traffic Light Control Unit (508) which enables
autonomous implementation of traffic light control by the device based on either Active
RFID signals received and processed by Intelligent Monitoring Unit (202) in terms of
relative vehicular density on each segment of a traffic junction derived from the Active
RFID data, or on the results of image processing of the Video Capture feed of the traffic
25 junction.
Fig-6 shows a preferred embodiment of the Processing Unit (504) in the Intelligent
Monitoring Unit (202) comprising Multimedia Processing unit (601) which incorporates
special capabilities for processing the video stream received from Video Capture Unit
30 (302). In particular it incorporates real-time multimedia encoding and compression
capability and may include hardware accelerators for this purpose. Preferably, the
multimedia encoding and compression is implemented in accordance with established
12
standards such as MPEG-3 or MPEG-4. The Multimedia Processing unit (601) also
includes capabilities for handling compressed multimedia streams received from distant
stations through Communication Unit (204). In particular it incorporates real-time
multimedia decoding and de-compression capability and may include hardware
accelerators such as Graphics Processors for this purpose. Application Processing 5 Unit
(602) incorporates high-speed general-purpose computational capabilities for
performing complex, real-time multitasking. Preferred embodiments incorporate 32-bit
or 64-bit single-core or multi-core embedded general-purpose processors such as from
the ARM family. In other preferred embodiments the Application Processing Unit (602)
10 may further include Digital Signal Processors (DSPs) to perform specialized signalprocessing
tasks, such as complex image processing and/or pattern recognition, in realtime.
In preferred embodiments, each “virtual presence” device makes synergistic use of the
15 available Input Sense unit capabilities to provide a more robust implementation of the
target applications. For instance, Processing Unit (504) combine inputs received from
Active RFID Unit (301) with results from image recognition functions performed on the
multimedia feed from the Video capture Unit (302) to provide more targeted and useful
data in Personal Emergency situations. Similar image analysis capabilities could enable it
20 to identify traffic violation incidents.
The Communication Unit (304) in the device is not limited to any particular type or
format. Further, the device may form part of a wide area network. In preferred
embodiments Communication Unit (304) may comprise one or radio-frequency links
25 such as Wi-Fi, ZigBee or other standard/proprietary RF. In another preferred
embodiment Communication Unit (304) incorporates a low-power RF means which
forms part of a wide area low-power network. In other embodiments Communication
Unit (304) may include optical-fiber links, power-line communication links and
conventional RS-485/RS-232 wired links.
30
13
In preferred embodiments multiple communication links and modes are implemented in
each “virtual presence” device so as to provide redundancy and implement faulttolerance.
Since each “virtual presence” device would typically gather data for several differen5 t
user groups or data clients (for example, visual and auditory inputs for crime monitoring
agencies such as the police, similar data of traffic conditions for the traffic police, and
air-quality and weather data for the Meteorological department), preferred
embodiments of the device incorporate secure tagging and identification of each of the
10 separate data segments in order to ensure integrity and reliability of inputs for each user
group.
The communication links also enable each “virtual presence” device to monitor the
status of neighboring “virtual presence” devices and report any malfunction, thereby
15 enhancing the reliability of the entire intelligent network.
Each “virtual presence” device is preferably designed to be scalable in terms of features
and capacity throughout its operating life with the ability of adding several functions
during regular operation, by remote upgrades of its functional capabilities. Such
20 capability enhancements are automatically detected and announced by the upgraded
unit and communicated to the designated monitoring station(s). Similarly, the addition
of any new “virtual presence” device (for example, by field up- gradation/replacement
of a normal street light to a “smart” street light) is preferable automatically registered
by the entire network and reported at the designated monitoring station(s) along-with
25 its capabilities and features.
Individual “virtual presence” devices preferably implement continuous or
periodic/externally-triggered self-health checks including status checks on input power
supply, and report the results of the checks to the central monitoring station(s) at
30 regular intervals/during normal communication sessions as well special transmissions on
the occurrence of specific events including, but not limited to, events such as input
power failure which is reported during the brief “hold-up” period of the internal power
14
supply. On resumption of power, the “virtual presence” device is able to automatically
re-configure itself to its status prior to the outage and re-register itself on the network
and then report its status to the designated monitoring station(s).
Each “virtual presence” device preferably incorporates special features to enhance 5 ce the
reliability of the data transfer to/from the designated monitoring station(s). The data
integrity mechanisms may include mechanisms for checking and validating the identity
of the source and destination of the data transfer, as well as the type and value of the
individual data elements. Wherever possible, error-correction mechanisms may also be
10 incorporated for recovering original information from corrupted data received at the
destination points.
In one embodiment, the “virtual presence” device also includes the capability to
securely encrypt data originating from it as well as decrypt data for which it is the
15 destination, in order to provide secure data transfer. As a further security measure, the
“virtual presence” device may include authentication mechanisms that verify the source
of data received by it as destination. Such measures may include “challenge-response”
mechanisms.
20 In one preferred embodiment, a “virtual presence” device includes GPS functionality to
self-determine its location and include this feature in its reports. The location data
provided by the GPS feature enables the reporting of location-specific information at the
designated monitoring station(s) so as to facilitate map-based information display.
25 Optional features include the ability of a “virtual presence” device to recognize and
report on external threats to its integrity. This ability is preferably enabled by
incorporation of proximity sensors and access-authentication mechanisms in the unit.
Such a feature safeguards against intrusion and/or sabotage attempts to compromise
the functioning of the “virtual presence” device.
30
Several embodiments are possible for the power source for the “virtual presence”
device including autonomous power units that power individual “virtual presence”
15
devices, as well as common power sources that power groups of “virtual presence”
devices or even the entire network.

WE CLAIMS:-
1. A device comprising:
- an intelligent monitoring unit (202) that analyzes signals received from one
or more external or internal sensing units (201), identifies the occurrence o5 f
specific conditions requiring action and determines an autonomous response
in accordance with defined operating parameters and functions; and
- one or more output units (203) provided at outputs of said intelligent
monitoring unit (202) which generate said autonomous response.
10
2. A device as claimed in claim 1 wherein said intelligent monitoring unit is coupled
to one or more communication units (204) which provide alerts and data
pertaining to said specific condition to one or more distant monitoring stations.
15
3. A device as claimed in claim 2 wherein, said intelligent monitoring unit (202)
comprises means for adapting operating parameters and functions in
accordance with inputs received from said one or more distant monitoring
stations.
20
4. A device as claimed in claim 2 or claim 3 wherein, said output unit (203)
comprises means for displaying multimedia inputs received from said one or
more distant monitoring stations after processing by said intelligent monitoring
unit (202).
25
5. A device as claimed in any of the preceding claims wherein, said internal or
external sensing unit (201) comprises Active radio frequency identification
(Active RFID) means (301).
30 6. A device as claimed in any of the preceding claims wherein, said internal or
external sensing unit (201) comprises Video Capture means (302).
17
7. A device as claimed in any of the preceding claims wherein, said internal or
external sensing unit (201) comprises Active RFID means (401), Video Capture
means (402), ambient light sensing means (501), dust particle sensing means
(502) and polluting gas sensing means (503).
5
8. A device as claimed in any of the preceding claims wherein, said intelligent
monitoring unit (202) comprises a Processing Unit (504) with associated
Memory (505) and Storage means (506).
10 9. A device as claimed in any of the preceding claims wherein, said Processing unit
(504) comprises a Multimedia Processing Unit (601) and Application Processing
Unit (602)
10. A device as claimed in any of the preceding claims wherein, said Output unit
15 (203) comprises Lighting Control Unit (303) and Audio Alarm unit (304).
11. A device as claimed in any of the preceding claims wherein, said Output unit
(203) comprises Multimedia Display Unit (401).
20 12. A device as claimed in any of the preceding claims wherein, said Output unit
(203) comprises Access Control Unit (507).
13. A device as claimed in any of the preceding claims wherein, said Output unit
(203) comprises Traffic Light Control Unit (508).
25
14. A device as claimed in any of the preceding claims wherein, said Communication
Unit (204) comprises Radio Frequency communication unit.
15. A device as claimed in claim 14 wherein, said radio frequency communication
30 means comprises WiFi.
18
16. A device as claimed in claim 14 wherein, said radio frequency communication
means comprises a low-power RF radio.
17. A method for providing local autonomous responses to monitored ambien5 t
conditions at a remote monitoring location, comprising the steps of:
- sensing specified ambient parameters;
- identifying defined conditions requiring response;
- determining an autonomous response in accordance with defined operating
10 parameters and functions;
- implementing said autonomous response; and
- communicating the occurrence of any of said defined conditions to one or
more distant monitoring stations.
15 18. A method as claimed in claim 17 incorporating the step of receiving and
implementing modifications to said defined operating parameters and functions,
received from said one or more distant monitoring stations.
19. A method as claimed in any preceding method claim incorporating the step of
20 receiving and displaying multimedia information received from said one or more
distant monitoring stations.
20. A method as claimed in any preceding method claim wherein, said sensing
includes the steps of receiving active RFID radio signals and identifying its source
25 and associated operating parameters.
21. A method as claimed in any of the preceding method claims wherein, said
sensing includes the steps of capturing and analyzing or relaying video
information pertaining to an area under observation.
30
22. A method as claimed in any of the preceding method claims wherein, said
sensing includes the measurement of ambient light conditions.
19
23. A method as claimed in any of the preceding method claims wherein, said
sensing includes determining ambient dust particle concentration levels.
24. A method as claimed in any of the preceding method claims wherein, 5 erein, said
sensing includes determining ambient polluting gas concentration levels.
25. A method as claimed in any of the preceding method claims wherein, said
autonomous response includes controlling the intensity of one or more light
10 sources.
26. A method as claimed in any of the preceding method claims wherein, said
autonomous response includes generating an audible alarm.
15 27. A method as claimed in any of the preceding method claims wherein, said
autonomous response includes controlling physical access to a defined space.
28. A method as claimed in any of the preceding method claims wherein, said
autonomous response includes controlling the operation of traffic lights at a
20 traffic junction.