advantage and disadvantage of bubble sensing .

advantages and disadvantages of bubble sensing

Introduction

We propose bubble-sensing, a new sensor network abstraction that allows mobile phone users to create a binding between sensing tasks and the physical world at locations of interest, that remains active for a duration set by the user. We envision mobile phones being able to affix sensing task bubbles at places of interest and then receive sensed data as it becomes available in a delay-tolerant fashion, in essence, creating a living documentary of places of interest in the physical world. The system relies on other mobile phones that opportunistically pass through bubble-sensing locations to acquire tasks and do the sensing on behalf of the initiator, and deliver the data to the bubble-sensing server for retrieval by the user who initiated the task.We describe an implementation of the bubble-sensing system using sensor-enabled mobile phones, specifically, Nokia’s N80 and N95 (with GPS, accelerometers, microphone, camera). Task bubbles are maintained at locations through the interaction of “bubble carriers”, which carry the sensing task into the area of interest, and “bubble anchors”, which maintain the task bubble in the area when the bubble carrier is no longer present. In our implementation, bubble carriers and bubble anchors implement a number of simple mobile phone based protocols that refresh the task bubble state as new mobile phones move through the area. Phones communicate using the local Ad-Hoc 802.11g radio to transfer task state and maintain the task in the region of interest. This task bubble state is ephemeral and times out when no bubble carriers or bubble anchors are in the area. Our design is resilient to periods when no mobiles pass through the bubble area and is capable of “reloading” the task into the bubble region. In this paper, we describe the bubble-sensing system and a simple proof-of-concept experiment.
A sensor (also called detector) is a converter that measures a physical quantity and converts it into a signal which can be read by an observer or by an (today mostly electronic) instrument.Sensors are used in everyday objects such as touch-sensitive elevator buttons (tactile sensor) and lamps which dim or brighten by touching the base. There are also innumerable applications for sensors of which most people are never aware. Applications include cars, machines, aerospace, medicine, manufacturing and robotics.The tremendous growth of sensor technology in Smartphone increases day by day and will experience fabulously over the next few years. Success of smart phones is leading to an increasing amount of MEMS & sensors in mobile phones to provide new features/ services to end-users, to reduce cost through more integration or to improve hardware performance.

Application

Area monitoring
Area monitoring is a common application of WSNs. In area monitoring, the WSN is deployed over a region where some phenomenon is to be monitored. A military example is the use of sensors to detect enemy intrusion; a civilian example is the geo-fencing of gas or oil pipelines.