TeleCARE: Collaborative virtual elderly support

communities

L. M. Camarinha-Matos

and H. Afsarmanesh

New University of Lisbon / Uninova,

Quinta da Torre, 2829-516 Monte Caparica, Portugal

University of Amsterdam,

Kruislaan 403, 1098 SJ Amsterdam, The Netherlands

Abstract. The growing percentage of elderly population imposes an urgent

need to develop new approaches to care provision. Integration of a number of

technologies such as multi-agent systems, federated information management,

safe communications, hypermedia interfaces, rich sensorial environments, and

increased intelligence in home appliances represents an important enabling

factor for the design and development of virtual elderly support community

environments. In this paper, a platform based on mobile agents combined with

federated information management mechanisms is introduced as a flexible

infrastructure on top of which specialized care services are built.

1 Introduction

One of the key challenges faced by modern societies derives from the fact that with

increasing speed our average population is getting older [11]. During the last three

decades, the number of people aged 60 years or more has risen by about 50% in

Europe. By 2020, it is estimated that for every person below the age of retirement,

there will be 4 elderly people requiring support and care from their community. The

impact on costs to the community will become considerably high. To deal with this

challenge, new ways of providing elderly assistance and care, namely resorting to

technological support, must be found.

New technological infrastructures, although not the solution for all problems, can

be part of a new concept of integrated care system. An integrated elderly care system

consists of a number of organizations such as care centers / day centers, health care

institutions, social security institutions involving the cooperation of a number of

human actors e.g. social care assistants, health care professionals, elderly people, and

their relatives. When based on computer networks and adequate supporting tools, the

collaboration among the care institutions may evolve towards operating as a long-

term virtual organization and the various involved actors become part of a virtual

community (VC).

In recent years various research projects have been engaged in developing

technological solutions to increase the care services and reduce their costs. For

M. Camarinha-Matos L. and Afsarmanesh H. (2004).

TeleCARE: Collaborative virtual elderly support communities.

In Proceedings of the 1st International Workshop on Tele-Care and Collaborative Virtual Communities in Elderly Care, pages 1-12

DOI: 10.5220/0002677300010012

 SciTePress

instance, various initiatives have established “social alarm” systems [13], namely in

the case of people living in remote and hard to access areas. Such systems comprise a

portable alarm trigger and an alarm telephone that dials a social alarm control center

when there is an emergency situation. More recent works are focused on mobile

social alarm systems and online monitoring systems based on a diversity of sensors

and other devices. Other projects are focused on the development of smart home

appliances or specialized user interfaces [7, 8]. Advances in computer networks and

ubiquitous computing suggest the opportunity for more advanced care approaches

including comprehensive status monitoring, other forms of assistance such as agenda

reminders, but also the creation of the opportunity for the elderly becoming involved

in the community, and thus reducing their feeling of loneliness.

In order to let elderly stay at home, and keep, to certain extent, their typical life

style, new support services are necessary to address, among others, the following

problems:

 Loneliness is one of the most serious problems affecting the elderly population.

Development of applications to enrich the elderly’s social life and avoid problems

of loneliness is of great importance. Fieldwork data [10] show that today the

elderly hardly participate in activities relating with others, and 16% of them

express dissatisfaction with their social lives. According to family members, 28%

of the elderly have little or no contact with other people.

 Interconnection between the homes of the elderly and the homes or

workplaces of the family members caring for an elderly person is important to

provide access to loved ones. According to a survey carried out with relatives

caring for an elderly person, 31% of them stated the need to be in contact with the

elderly person (currently done either by phone or personal visits) at times when

they are alone.

 Widening the interconnection to also include entities dedicated to providing

different services for the elderly, such as the residential centers, social centers,

and social services, will bring potential benefits to the elderly. These

interconnection systems, based on using new technologies, would reduce the

loneliness problems of the elderly, would avoid the need for care workers to travel

each time a person who needs some sorts of assistance or a company, and would

permit continuous contact with the elderly person without the need for being

physically present.

A crucial issue when developing a system to provide care and assistance, whilst

preserving the elderly person’s independence, is the privacy assurance, and special

care must be invested in mechanisms that will protect the elderly person’s privacy.

In this context, the IST TeleCARE project [3, 4, 5] aimed at the design and

development of a configurable framework focused on virtual communities for elderly

support. The proposed solution has to be seen as complementary to other initiatives

for the integration of elderly in the society and reduction of their isolation. With

different organizations developing different products and services, in a variety of

different areas, there is a need for a common platform into which all these

developments may be plugged so that interoperability is possible. The TeleCARE

project proposes such a common and extendable platform as a common infrastructure.

2 TeleCARE platform

The TeleCARE approach for aiming at a technological infrastructure to enhance the

collaborative virtual elderly support communities resorts at the base to the Internet

and mobile-agent technologies (Fig. 1). Internet, although appealing as a base

infrastructure, itself raises some difficulties, such as:

i) In application domains such as elderly care, high levels of heterogeneity are

expected in the sensorial and equipment richness of the remote places (homes),

which demands appropriate solutions to guarantee the necessary levels of

flexibility and scalability;

ii) The Internet is characterized by long and variable time-delays and, very often,

suffers from low levels of availability, raising new challenges in what concerns

the reliability of the implemented system and its dependence on the

characteristics of the network;

iii) The emergence of mobile and ubiquitous computing raises the importance of

wireless connections where the actual connection to the network has to be

reduced to short periods;

iv) The execution environments, involving legacy components, are potentially

unstructured and uncertain, which means that it is difficult to cope with these

environments by resorting to deterministically programmed systems.

The mobile agents paradigm offers interesting characteristics that in fact directly

addresses the above issues [6]:

i) Moving the code to the place where actions are required enables real-time

response, autonomy and continuity of service provision with reduced

dependency on network availability and delays;

ii) Since new mobile agents can be built and sent for remote execution whenever

needed, higher levels of flexibility and scalability are achieved.

Fig. 1 – The TeleCARE approach

Fig. 2 shows a block diagram of the TeleCARE infrastructure to support collaboration

in the elderly care virtual organization [2, 5]. The Basic Platform is intended to be

installed at each node of the TeleCARE network. The Specialized Components

(vertical services) have a distributed implementation over the TeleCARE network.

The three-level infrastructure comprises:

• External Enabler Level: Supports the communication over the network and

interfacing to the external (local) devices. In specific it includes:

a) Safe communications infrastructure, that provides safe communications –

supporting both agent mobility and inter-agent message passing. A virtual private

network (VPN) approach is adopted; in critical cases where communications

reliability is mandatory redundant channels, in addition to Internet, may be

supported and hidden by this layer.

b) Device abstraction layer, interfaces to the sensors and monitoring devices and

other hardware (home appliances, environment controllers, etc.). These interfaces

represent the bridge to any “intelligent home” or “local domotics network”, hiding

aspects such as low-level protocols, wire-based or wireless communications, etc.

UPnP [12] is one of the approaches adopted to interface devices.

Core MAS Platform Level

Inter

platform

Mobility

Enter-

tainment

service

Safe Communications

infrastructure

Devices abstraction layer

TeleCARE Basic Platform

Specialized

Components

Inference

engine

Basic Multi

Agent Platform

Ontology

Managem.

Inter-agent communication

External Enabler Level

Vertical Services Level

Virtual Community

Support

Status

Monitoring

service

Time

Bank

service

Specialized interfaces

for elderly

Agent

Reception &

Registration

Agent

Exit

Control

Persistence

Support

Module

Agenda

service

Federated Information

Management

Agent

Factory

Resources

Managers

Platform Manager

Resource Catalog

Management System

FIMA

Dynamic

Schema generator

Web services

access

Fig. 2 - The TeleCARE platform architecture

• Core Multi-Agent System (MAS) Platform Level: It is the main component of the

basic platform. It supports the creation, launching, reception (authentication and some

rights verification), and execution of stationary and mobile agents as well as their

interactions. It supports the storage and manipulation of data and information to be

handled within TeleCARE. It provides a catalog of all devices and services supported

in TeleCARE. As intelligent agents are envisaged, an inference engine is included.

Main modules in this layer are:

a) Basic multi-agent system (MAS) platform (based on AGLETS).

b) Inference engine (based on a Prolog interpreter).

c) Ontology support (based on Protégé). A facility is developed providing the basic

mechanisms for dynamic schema description by TeleCARE service developers.

d) Persistence support – Extension to the MAS platform, providing some basic

recovery mechanisms in case one node goes down.

e) Inter-platform mobility – Extension to the basic MAS platform to support

generalized mobility of agents, including security mechanisms. This module

includes the Agent Reception & Registration component (for incoming mobile

agents) and the Agent Exit Control component (for outgoing mobile agents).

f) Inter-agent communication – Extension to the basic MAS platform to support

communication between / coordination of agents independently of their current

location, via FIPA ACL messages.

g) Platform manager – To specify and configure the operating conditions of the

platform in each site, recover from errors, monitor operation status, etc. It

includes:

• Agent factory – A module that supports the creation / specification and

launching of new agents.

• Resource manager agents – To provide a common and abstract way of dealing

with devices and appliances in TeleCARE.

h) Federated information management – To support the necessary management of

information while preserving the information privacy and careful control of access

rights to local data for external users. This module, installed in each site, is the

local component of the Federated Information Management Architecture (FIMA),

which includes:

• Federated query processing – providing the possibility to retrieve information

from a number of TeleCARE nodes.

• Federated access control – querying and providing access to the stored

information.

• Automatic ontology-based schema generation – generating database schemas

from the ontology definitions provided by TeleCARE software developers.

i) Resource catalog management – To manage the catalogue of resources including

support for their specification, discovery, and access proxies of all devices and

services available at each site.

• Services Level: This is the application level and consists of two sets of specialized

services:

a) Base horizontal services

– A set of specialized base services that provide specific

functionality for the other (vertical) services, including the following:

 Specialized interfaces for elderly – In the case of home sites, specialized

interfaces are required for elderly that are not familiar with the use of

computers. The ultimate goal is therefore to make the usage of the system

pleasant and easy, and thus to make the TeleCARE infrastructure "invisible" to

the elderly.

 Virtual Community Support – To support and facilitate the creation and

operation of community-based services designed for the elderly. For this

purpose, specific virtual community management functionalities are supported

within the service development environment of TeleCARE.

 Web service access – To allow remote access to some services via a web

browser. This functionality is particularly useful to allow relatives of elderly to

have access to the TeleCARE network from their working places.

b) Vertical Services

– A set of specialized vertical services can be implemented on

top of the horizontal TeleCARE infrastructure defined in the previous levels to

support different interactions with the system. Taking into account the priorities

identified through an extensive fieldwork, the following initial services have been

developed by the TeleCARE consortium:

 Living status monitoring. This service represents an advance regarding the

more traditional “social alarm” systems, as it allows not only bi-lateral

interactions and some semi-automatic supervision functionalities, but also the

collection of additional information when help is needed or requested. The

tranquility and assistance given 24 hours a day increase in a significant manner

the elderly’s quality of life and relative’s peace of mind.

 Agenda reminder. The daily activities related to the welfare of the elderly can

be easily scheduled in order to improve their quality of life and well being.

This service, implemented through a number of agents, is able to remind the

elderly of a number of activities, ranging from medication to exercise guidance

or appointments made with the care center.

 Time bank. This service provides a mechanism for collaborative community

building / re-enforcement, i.e. a way for people to come together and help each

other. At the same time it represents one of the mechanisms to support the

“active aging” concept.

 Entertainment. The Entertainment Services are designed to ease the sense of

isolation elderly feel and provide light entertaining applications to improve

their sense of well being, contributing to the maintenance of a social life and

also an active aging. As a first demonstration a combination of games, music

and education programs are offered.

3 TeleCARE platform implementation

A TeleCARE prototype platform is developed in Java that integrates and resorts to

various open source or freeware supporting technologies, e.g. AGLETS mobile agents

platform [1], Protégé ontology manager, SAP DB management system, and

CASTOR.

Fig. 3 – TeleCARE interface for the care center

In order to support the requirements of this application domain, a number of

innovative technical features and components are developed as the middleware on top

of the base development environment. Following is a list of these features and

components, with some details about their implemented capabilities:



Inclusion of agents’ persistence support. Persistency is a mechanism that allows

storing information about the running activities of the agents and, whenever a

system crashes to allow them to be resumed when the system is restarted.

AGLETS provides a method called

snapshot, which saves a snapshot of an

agent into a secondary / non-volatile storage. For persistency purposes, every

TeleCARE agent can invoke the

tcSave method, which does a call to snapshot,

for storing information about its execution status when necessary. If there is a

system failure, the last snapshot of the agent is restored and its execution can be

resumed with the information stored in that snapshot. In the current version,

automatic support for persistency is provided on three events: (i) at the creation of

the agent, (ii) just after the agent arrives to a new location, and (iii) when the agent

is activated. It is up to the developer to decide where he/she wants to make

additional snapshots of his/her agent, calling the

tcSave method.



High-level agent identification and localization. A TeleCARE Logical Agent

Identification (TLAID) structure was introduced, which is used to validate an agent

at any platform, and to locate an agent (using human understandable data) as well.

With the information provided by the TLAID, the developers can identify any

TeleCARE agent, given its name, type, role or user ID, and/or domain node of the

TeleCARE Virtual Organization that the origin host (or platform) of the agent

belongs to. TLAID is composed of two substructures:

– TLAD – The TeleCARE Agent Data that contains specific human readable

identification of the agent, and

– TLUD – The TeleCARE User Data that contains human readable

identification of the user who created the agent;

Please note that the native AGLETS AgletID, which is a string of 16 hexadecimal

characters, is not a user-friendly identifier. Furthermore, it might change if a clone

replaces the original agent as a result of the persistency support mechanisms.

TLAID is, therefore, a high-level user-friendly identifier. If only part of TLAID

information is given, the result of the method

tcGetAgentTAL can be a set of

agents. This happens when a TLAID object is used to get the TAL or passport of an

agent. In many cases the result of the query is a set of agents.

Given the inter-platform mobility and the need to keep track of mobile agents, the

following agents are introduced:

 Agent Registry – Keeps a record of all agents that are living in the platform.

The registration consists in a copy of the passport of each agent..

 Agent Reception Control – Responsible for the reception of the incoming

mobile agents. Depending on their passports these agents can be accepted or

refused. Whether an arriving agent is accepted in the local platform or not, the

Agent Exit Control of the sender platform is notified..

 Agent Exit Control – Controls the outgoing of mobile agents. Every time an

agent is to leave the platform, its passport is first checked to see if the agent

has permission to travel, and if the destination of the agent is available and/or

is a valid TeleCARE platform.



New security mechanisms for agents and messages. Both in case of mobile agents,

when an agent arrives at one node, or remote (inter-node) agent communication, it

is important to know who the agent is / who it represents. For this purpose, the

concept of passport is introduced and associated to each agent (Fig. 4). It is the

official “travel document” recognized by any TeleCARE site of the community.

Any mobile agent that intends to migrate to another platform must have a valid

passport.

The passport includes two fields used for agent identification: TAL and TLAID.

TAL is the TeleCARE Agent Locator, which is a system identifier used to locate an

agent; with the information provided by TAL, the system can find the proxy of any

agent, no matter where it is (for instance, to send it a message).

TAL

Passport

The Aglets

identification

Platform where the

Agent was created

TAL

TLAID

TLAID Validity Itinerary

AgletID hostOrigin hostCurrent agentName agentType userRole userID

Platform where the

Agent is currently living

Logical name of

the Agent, given

by the Developer

The category of the

Agent: System,

Resource, etc.

Category of the user who

created the Agent: Doctor,

Nurse, Relative, Elderly, etc.

The identification of the

user who created the

Agent: Mary, Joseph,

etc.

Duration time

of the Passport

List of the last

visited sites

domainNode

TLAD

TLUD

Domain node of the

TeleCARE VO to which

hostOrigin belongs to

TeleCARE

Agent Locator

TeleCARE

Logical Agent

Identifier

Fig. 4 - TeleCARE agent passport

 Generalized communication mechanisms. The AGLETS system provides a simple

mechanism for inter-agent communication. However this mechanism is not

sufficient for reliable communication for highly mobile agents [9] or when

persistence mechanisms based on cloning are implemented, namely due to the

changes in the AgletID. Therefore, the platform implements additional

communication services:

 Extended message exchange mechanisms, which allow reliable inter-agent

communication.

 Handling FIPA ACL messages.



Integration and management of resources in TeleCARE. Two kinds of resources

are considered in TeleCARE including the hardware devices and the software

services. The Universal Plug and Play (UPnP) specification is an architecture for

pervasive peer-to-peer network connectivity of intelligent appliances, wireless

devices, and PCs. Home appliances and sensors are connected to the TeleCARE

platform following UPnP. The Web Services Definition Language (WSDL)

provides the framework for definition of service specifications and their

interfaces. The horizontal and vertical services of TeleCARE are defined and

provided through the TeleCARE platform using the WSDL.

The Resource Catalog Management (RCAM) component supports the

organization, storage, and access to the UPNP (for devices) and WSDL (for

services) definitions of the TeleCARE resources.

Furthermore, in order to facilitate the access to & invocation of TeleCARE

resources an Abstract Resource Manager Agent (ARMA) template is provided.

ARMA is instantiated and customized for each resource, becoming its actual

Resource Manager. Application services can access a resource’s functions through

its corresponding Resource Manager that also checks and enforces the access

rights of the requesting agents on the requested resource.



Integration of federated information management and mobile agents. The

Federated Information MAnagement (FIMA) is a key component of the 'Core

Multi-Agent System Platform Level'. FIMA enables applications to distribute data

transparently across multiple machines within the TeleCARE network. The design

of FIMA is based on the federated databases approach, in order to support

cooperation and information sharing, while reinforcing the required level of

autonomy and heterogeneity among individual data sources (e.g. elderly home,

care center, leisure center, etc.) within a TeleCARE network. The federated query

processing is implemented by MIRA - Mobile Information Retrieval Agent in

such a way that applications can request to execute queries in:

• parallel mode, e.g. accessing data from several remote sources simultaneously.

• serial mode, e.g. accessing data from different nodes, one after the other, etc.

• sequential mode, e.g. similar to the serial one but in which the process can be

stopped once the client is satisfied with the result, providing a high user

interactivity to control information processing overhead.



Ontology-based database schema generator. The Dynamic Ontology-based

Schema Generation (DOSG) component of the core platform of TeleCARE

supports and assists service developers with their direct definition of database

schemas for the data that needs to be stored and processed by their code, and thus

it can eliminate the need for database experts to define and modify these schemas.

Namely, DOSG provides facilities for dynamic and automatic definition of the

database schemas (relational and XML schemas) and the (Java source) code for

the structures defined by users, so that they can be automatically stored into

database and processed by application programs. As such, the service developers

of TeleCARE, can use the ontology system “Protégé” as interface for their

structure definitions, and do not need to have database expertise to define these

database schemas.



Integration of web services. In order to provide access to TeleCARE services for

relatives having access to Internet through a web browser, a mechanism is

implemented to provide a bridge between the multi-agent platform and a web

browser following a philosophy of web services.



Integration of biometric security. A finger print identification device is integrated

with the platform providing a mechanism to implement safer user identification.

This is particularly useful in the care centers where different users (e.g. nurses,

doctors, care workers), with different information access rights, can have access to

the system. A taxonomy of users and roles is therefore associated to the biometric-

based login process.



Variety of user interfaces. Considering the diversity of computer skills of the

various actors in the elderly care virtual community, access to the TeleCARE

platform and services needs to be made accessible through a variety of user

interfaces, namely for users with computer skills (e.g. care center workers having

direct access to the platform, relatives having access through a web browser from

their work locations, or elderly without computer skills interacting with the system

through a TV set).

4 TeleCARE services implementation

In the TeleCARE environment each vertical service can be implemented in different

ways as a set of distributed stationary and / or mobile agents. For instance, a

monitoring service might involve a stationary agent in the care center (interacting

with the care worker), a number of stationary agents in the elderly home (agents in

charge of monitoring local sensors, e.g. temperature sensor, presence sensor), and

some mobile agents sent from the care center to the elderly home (Fig.s 5, 6). The

mobile agents might carry a mission, for instance MIRAs sent to collect information

from different sensors and to report back to the care center.

The stationary agents in one platform can also communicate, via ACL messages,

with other mobile or stationary agents residing at another platform. Since a

TeleCARE message includes the extended agent identification (see passport section),

the receiver of a message can check the identity and rights of the sender, no matter at

which location it is running at the moment.

Care Center

Elderly Home

Internet

Monitoring

Application agent

Care worker

Specific

Monitor

agents

Mobile agent

with monitoring mission

TeleCARE Platform

TeleCARE

Platform

ACL

Fig. 5 - Example of service implementation

The use of mobile agents facilitates the remote deployment of the service

functionalities according to the services subscribed by each elderly. As different

elderly have different needs, such flexibility is required. With this mechanism it is

also easier to install updated versions of the services.

CARE4U

Fig. 6 - Example of monitoring service interfaces at elderly home and care center

An integrated prototype system including the TeleCARE platform and a set of

demonstration services was developed, showing the feasibility of the suggested

approach. This integrated system was partially validated through a field assessment

phase that took place in South of Spain, and involving four classes of potential users:

(i) Elderly and relatives, (ii) Care providers / care workers, (iii) Decision makers (on

social policies), and (iv) Software developers. The TeleCARE concept and its

provided functionalities were well accepted by these potential users, although it is

clear that the system is at a research prototype stage and substantial engineering work

is still necessary in order to make it a robust product.

5 Conclusions

The growing numbers of elderly population impose an urgent need to develop new

approaches to care provision. Recent developments in a number of technologies such

as multi-agent systems, federated information management, safe communications,

hypermedia interfaces, rich sensorial environments, and increased intelligence of

loud

home appliances represent an important enabling factor for the design and

development of virtual elderly support community environments. In particular, a

platform based on mobile agents combined with federated information management

mechanisms provides a flexible infrastructure on top of which specialized care

services can be built. Nevertheless, the specific characteristics of the elderly

population, not very open to deal with new technologies, require a careful integration

of the infrastructure with traditional home appliances and TV sets. Furthermore, the

tuning and eventual acceptance of the technology can only be determined when

reliable prototypes are tested in field with real users. This field trial constitutes the

next phase in the TeleCARE project.

Acknowledgements.

This work was funded in part by the IST program of the

European Commission. The authors thank the contribution of the TeleCARE

consortium members (Uninova, University of Amsterdam, SKILL, RoundRose

Associates, Camera de Comercio de Navarra, and Synkronix).

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