Implementing a Sentient Computing System

Presented by:

Jing Lin , Vishal Kudchadkar ,

Apurva Shah

Sentient Computing Systems

Sentient computing systems are systems which can change their behavior based on a model of the environment they construct using sensor data.

Sentient computing systems may hold the key to managing tomorrow’s device-rich mobile networks.

Implementing a Sentient System: Active Bat (1) Location sensing

Implementing a Sentient System: Active Bat (2) Current Embodiment

Accuracy and Precision 95% of 3D Bat position readings are accurate to within

3cm Maximum Location update rate across each radio

cell 150 updates per second

Implementing a Sentient System: Active Bat (3) Scheduling and power saving

The scheduling process allows the Bat to enter a low-power sleep state.

A 10-bit local ID is used to achieve shorter addressing message and power saving.

Nonmoving Bats are placed into a low-power sleep state.

Modeling the Environment

Use data from sensors and from services Filter the incoming location data using

knowledge of tracked objects’ dynamics Update the world model using filtered data Increase fidelity of the model by determining

if someone appears to be seated

Software Support for Sentient Systems Spatial monitor

Formalizes imprecise spatial relationships in terms of containment and overlapping relationships between suitable 2D spaces

Timeline-based data storage

Data generated by network appliances should be stored in a way that does not require the user to specify its destination.

Applications (1)

Browsing Model browsers display the environment’s current

state, e.g., continuously updated map displaying personnel, furniture, telephones, workstations and other relevant information

Follow-me Systems Services are made ubiquitously available to

“users” by moving their interfaces to the nearest appropriate input or output device

Applications (2)

Novel user interfaces Mice Virtual buttons Augmented reality

Data Creation , Storage and Retrieval.

Future

Sentient computing is more than a solution to the problems of configuration and personalization.

The environment itself will become the user interface.

Limitations

Active Bat requires a large fixed-sensor infrastructure throughout the ceiling.

The system is sensitive to the precise placement of sensors.

Therefore, there are disadvantages in scalability, ease of deployment, and cost.

Location Systems For Ubiquitous Computing

By

Vishal Kudchadkar ,Jing Lin ,

Apurva Shah

Introduction New mobile systems will need to know the

location of the things. Location sensing techniques …..

Triangulation : uses of multiple measurements from known points to find the location

Proximity : measure nearness from known points Scene analysis : exam a view from particular

vantage point

Location

Physical Location and Symbolic Location Symbolic Location encompasses abstract ideas of where

something is. Absolute versus Relative

In absolute system a frame of reference is shared by all the objects.

In a relative system each object will have it’s own frame of reference

An absolute location can be transformed into a relative location – relative to a second point of reference

Localized Location Computing

Some systems have location computing capability and insist that they compute their own locations and hence can protect their privacy.

Some systems require objects to periodically respond to a broadcast to tell their position to the system.

Qualities of a Positioning system

Accuracy and Precision:

The distance or grain-size denotes the accuracy. Sensor fusion can help improve accuracy. We generally determine the accuracy of the system by checking if it is suitable for the application

Scale :

Consider coverage as the area per unit of infrastructure and the number of objects the system can locate per unit area.

Qualities of a Positioning system

Recognition : Applications may take specific action depending on the location of the object and hence location recognition is needed in such systems

Cost : Time Cost includes time to install and setup the system and Space cost is the space the system requires

Limitations :Systems may not function in a specific environment.

Survey of Location Systems

Active Bridge, Active Bat, Cricket, Radar MotionStar magnetic tracker, Easy Living, Smart Floor E911

are discussed in the paper. We will present one of the systems in detail in the following paper.

Research Directions

Sensor Fusion: Defined as the use of multiple sensor

technologies to create hierarchical and overlapping levels of sensing

Ad hoc Location sensing : This method uses techniques to locate objects

without the use of a central information center or a browser

In this method of locating objects , the nearby objects share information to build about the system

Research Directions (Contd.)

Ad hoc Location sensing : Triangulation, scene analysis or proximity

location sensing methods are used Location – sensing system accuracy

Strength And Weaknesses

Strength A good introductory paper on location systems. It compares pros and cons of various location

systems. Provides a taxonomy which can be used to

evaluate the suitability of a location system. Weakness

This paper addresses only hardware issues but fails to address software issues.