AAL Demonstrator

Research in the personalised health domain within CLARITY concerns a number of associated areas of this domain. For the main part, research effort focuses on Ambient Assisted Living (AAL). AAL , as a concept, has been formulated in response to the demographic imbalance that will arise in coming years as the number of people at work will be increasingly outnumbered by those who are retired. Many problems may envisaged arising from this imbalance; thus research in AAL at this time is a societal imperative.

Recalling the objective of demonstrators in the CLARITY framework, the AAL implementation incorporates contributions from all CLARITY Research Programmes (RPs). The design of the demonstrator is influenced by the Ambient Assisted Living roadmap, published by AALIANCE [LINK], a coordination Action funded by the European Commission (EC), under FP7. This envisages four strands of support - AAL@Home, which aims to support the elderly in their homes; AAL@Mobile, which focuses on mobility and activity management; AAL@Community, which seeks to facilitate the elderly to contribute to and participate within social and community activities; and AAL@Work which is concerned with the support of the elderly in work environments. Ultimately, the demonstrator will address all four objectives; however, the initial version will focus on the AAL@Home and AAL@Work streams.


Heterogeneity and complexity are characteristic of AAL. This is expressed in the diversity of the end user population, in terms of their needs and the environments in which they live. Addressing this diversity call for a solution that is open, responsive, scalable and robust. Furthermore, ambience must be achievable in practice, rather than being just aspirational. Likewise, AAL must be perceived by the elderly as serving a specific function(s), one in which they have a direct interest. Otherwise, AAL systems will not be adopted and its potential unexplored, a situation that may have fatal consequences.



From an architectural perspective, the demonstrator may be regarded as comprising 3 layers - Sensor, Middleware and Interaction.

Embedded Sensor Layer

A range of sensors including contact pressure and motion sensors have been deployed. These are attached to everyday objects such as bins, doors and so on. The core sensor about which the configuration is constructed is the Tyndall 25 mm mote platform. A modular approach to design has been adopted negating the need to replace the node infrastructure should a change in wireless technology, sensing capabilities or power supply be required. The platform implementation consists of a variable number of layers that are stacked on top of each other in order to satisfy application requirements. To date upwards of 30 system layers have been developed. From a wireless ISM band perspective the platform is Zigbee/802.5.4, and Bluetooth compliant. Additional wireless transceiver layers available operate at 433, 868 and 915 MHz. The Atmel ATmega128 micro-controller is employed for onboard processing. Over 20 modular sensor layers have been developed some of which are specifically intended for use in the pervasive healthcare space. In the context of the AAL the platform has been employed to gather temperature, humidity, light level, vibration, orientation and mobility information from the ambient environment.

Intelligent Middleware Layer

Controlling the hardware layer is a middleware constructed around the embedded agent paradigm. Agents can be associated with individual devices or can be used to control groups of sensors. By acting in a collaborative fashion, activities can be identified and daily routines constructed. Deviations from these routines can be identified and appropriate alarms raised.

Within the AAL demonstrator we employ the SIXTH middleware framework to support application development. This middleware exhibits features such as reusability, flexibility, modularity, openness and intelligence. Using this middleware, applications can reuse existing components for the entire range of devices that comprise the distributed application. Components can potentially be replaced automatically in response to a changing environment.

Current middleware offerings for sensor networks tends to encompass systems that can aid application development between the application layer and the OS layer of the sensor. While this broad definition includes many solutions, there are two key goals: to facilitate application development and to provide the capability of deploying a sensor network with little in depth knowledge of sensor networks. The SIXTH Middleware platform, under development in CLARITY, is in keeping with the existing goals of WSN middleware but also provides additional capabilities: modularity, flexibility, reusability, openness, extensibility, universality and multiple abstractions. One of the primary goals of SIXTH is to create reusable components capable of intelligent behaviour which can be brought together to form the application. The SIXTH middleware is therefore the collection of components along with their integration. On a macro level this means that the application uses the middleware components and each component may be part of many applications. Given the uniqueness of the sensor devices, it is important that many applications can coexist on the same sensor infrastructure and this is achieved via the agent paradigm.

Visualisation & Interactivity

Though the interaction modality with AAL will be essential implicit in the first instance, there will be occasions where explicit interaction is necessary. Given the inherent complexity, circumstances may arise where the status of the elderly needs to be confirmed, particularly if their safety is potentially compromised. Thus, AAL systems must initiate interactions through a range of everyday devices including telephones and TVs for example.

In many cases, it is carers and family members that may need to interact with AAL systems. Their needs are different, as are their motivations. invariably, they will seek reassurance that the elderly person is coping and that their behaviour routine is consistent. To meet this need, a separate interface has been developed. This allows carers replay the activities of the elderly person as identified by the embedded sensor networks. This incorporates a series of icon representing monitored actions and enables them to be placed in a spatial and temporal context.


It is planned to address this objective in the second phase of the project.


It is planned to address this objective in the second phase of the project.

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