Senior Research Paper – Literature Review

Sensors and Actuator Network Based Architectures and Protocols for Smart Homes

Beyond the Smart Home, Tatsuya Yamazaki

The article addresses the future of smart home technology and points out the flaws in previous home automation technologies and how to improve upon the research that has been conducted. The author points out several key facts in the development of smart homes from the users’ standpoint. Their needs to be improvement in the development of interface technologies between humans and systems for detection of humans’ intensions, feelings and situations.

The introduction of home automation (HA) in the 1970s failed to improve the lifestyles of users for several reasons. Firstly, determining economic benefits of HA technologies is difficult. The costs of implementing smart home technology must be justified by the effects brought about by their installation. There is a need for HA technologies to be cost effective, easy to install and flexible with many network infrastructures and appliances.

The article briefly surveys the research accomplished in the past decade. It highlights the importance of building smart home environments in which users can be monitored while testing and research is accomplished. A trend in each of the projects described is the use of sensors and actuators that intelligently acts upon the environment through controllers. The smart home that is described in this article was constructed using cameras and microphones installed in the ceilings as well as floor pressure sensors and infrared sensor to track the movement. The home is highly networked and autonomously controls appliances on the home network based on sensor information.

An Integrated Wireless Sensing and Mobile Processing Architecture for Assisted Living and Healthcare Applications.

This article presents a wireless solution for monitoring people in need of medical assistance. The application relies on the use of cell phones and inexpensive sensors and is best suited for the elderly and home-bound people. The main functions of the project is to collect signals through a wireless sensor network using protocols like ZigBee and Bluetooth and the analysis for data through an adaptive architecture that produces real-time heath-monitoring system to improve medical support for people in their homes and in assisted living environments.

The article highlights a general architecture framework that consists of three major parts. Firstly, medical data is collected from sensors and transmitted to mobile devices through a wireless sensor network. Secondly, collected data is processed by a J2ME application running on mobile devices. Finally, the data collected and combined with data from other sensors to decide on an appropriate action.

The advantages of this approach are that it does not require costly equipment, specialized infrastructure or a challenging learning curve. It can be deployed in a short period of time at a very low cost.

Sensor/Actuator Networks in Smart Homes for Supporting Elderly and Handicapped People

This article describes the challenge regarding smart homes, especially for supporting the elderly and handicapped, is to compensate for handicaps and support the individual in order to give them a more independent life for as long as possible. This paper covers a common architecture for smart home environments is developed, mapped to an experimental setup, and finally evaluated.

A set of objectives is outlined that are of particular concern to an elderly or handicapped person. The higher level goal is to compensate any limitations in any part of his life as far as possible and to enable the patient to live a more independent life as long as possible. The first objective outlined is the development of a sensing and monitoring system, which takes over for the subjects senses and if necessary maintaining the capacity to remember. The purposed architecture takes care of domestic systems such as air conditioning, lights and heating as well as the basic functions of home entertainment and security systems. Lastly, the need to interact with physicians and to get the vital signs and values checked in a mobile manner, and if necessary, make emergency calls. This technology must be transparent and easy to use.

Several sub-networks were used in the implementation which includes Bluetooth, Wireless LAN, Radio Frequency ID (RFID), Internet (TPC/IP) and the telephone network. A Bluetooth network is used to interconnect the nodes and to transport sensor data over the network. The RFID system provides the possibility to transmit data from the RFID tags that are recording occupancy locations.

The messages being transmitted are broken down into 3 specific categories and assigned priorities. The first describes Emergency messages that are provided by temperature, light and motion sensors. Second is command messages used for re-calibration of sensors. The third message is data that is transmitted to and from the sensors and actuators.

The gateway used, which acts as the bridge between the in-home network and the outside world was an apache web server. This was used to gather the data produced by the sensor network to make it available from outside the smart home. Their approach sends messages via Bluetooth using the available Bluetooth module on the nodes. This means no further hardware is required and additionally no further costs arise.