A Bind Control Model For Real-space Programmingin Ubiquitous Computing Environment
Takuya Kashima, Shunsuke Saruwatari, Hiroyuki Morikawa, Tomonori Aoyama
The University of Tokyo
7–3–1 Hongo, Bunkyo-ku, Tokyo, 113–8656, Japan+81 3 5841 6710
{kashima, saru, mori, aoyama}@mlab.t.u-tokyo.ac.jp
ABSTRACTThis paper describes a Bind Control Model of an ANTH
(ANtennary THings) framework. ANTH is a framework
to program a physical environment in ubiquitous computing environment. The Bind Control Model is one of the key
technologies of ANTH framework. It is a mechanism to control bindings between objects and objects around us, and themechanism is designed to run on tightly limited computingresource. We show the details, basic operations, and an implementation example, of the Bind Control Model.
Keywords

service synthesis, real-space programming, networked embedded system
INTRODUCTION

In ubiquitous computing environment, communication andcomputation functions are embedded in every object aroundus, and this enable us to synthesize various services by combining these objects.
Many service coordination frameworks, such as UPnP, Jini,and Bluetooth, have been proposed until now. These frameworks are useful to construct conventional services or staticservices, because they are designed for configuring devices
automatically or replacing cable with wireless. These technologies remove annoying entwining cables and complex
device configuration from us. However, they never provide
us creative environment that enables us to construct variousservices.
In view of this, we are developing real-space programming
framework called ANTH (ANtennary THings) for ubiquitous computing environment. ANTH aims to construct programmable real-space that enables us to create our desired
services by ourselves. ANTH provides a chip that has threecharacteristic functions: a user interface function that controls connecting one device and another device, a communication function that constructs a network infrastructure fordevice cooperation, and a computation function which drives
devices and processes applications. The chip is called ANTH
chip, and an object that equips an ANTH chip is called ANTHobject. We assume, in the future, ANTH chips are embedded to all everyday objects around us, such as alarm clocks,
lights, walls, and so on.
The following describes a Bind Control Model that is one ofthe key technologies of ANTH framework.

describes the relations among the factors. Although the Bind
Control Model is very simple, it enables us to make device
cooperation easily and flexibly because it has the following
features and advantages.
• By introduction of a controller, the Bind Control Model
provides not only a device cooperation mechanism, butalso a user interface mechanism for users to coordinate
device cooperation easily.
• The communication among ANTH objects is only transmission of ANTH addresses. Therefore, ANTH does not
require high bandwidth. An ANTH address is GUID (GlobalUnique ID). Every ANTH object has a different ANTHaddress as an initial value.
• In processors on ANTH nodes, every task is combinedwith an ANTH address. This simplicity of computing
architecture can be realized in low computing resource,and gives extensibility to the ANTH node.
The following describes the details of the three factors inFigure 1, basic operations of the Bind Control Model, andthe possibility of the ANTH application on this model.
ANTH Objects
EN (Emitter Node)

An EN is an event emitter like a switch, a timer of an alarm, apressure sensor that is embedded in a chair, and so on. EachEN holds an ANTH address. When an EN detects an event,the EN emits the event packet including its ANTH address
to ANTH network.
SN (Sympathizer Node)A SN is an event receiver like an overhead light, a bell ofan alarm clock, on/off of a coffee maker, and so on. Eachcontroller
ANTH Address
Set ANTH Address
Get ANTH Address

Get ANTH Address
Logical Link

EN Address
ENSN Address

EventAction
Event Propagation

A BIND CONTROL MODELANTH object has three factors: an emitter, a sympathizer,and a controller. Figure 1 shows a Bind Control Model thatFigure 1: A Bind Control ModelSNSN holds an ANTH address. When a SN receives an event
packet, the SN checks its ANTH address. If the ANTH address of the received packet and the ANTH address of theSN are the same, the SN takes an action.
Controller

A controller is a user device that coordinates the relation between an EN and a SN like the mouse on real-space. Thecontroller can get and set ANTH addresses of EN and SN
freely, and realizes real-space programming by the combination of these operations.
Basic Operations

ANTH application is a set of relations between an EN and aSN, and real-space programming is bundles of the relations.
For example, ANTH application is built by describing a relation like “turn on the light if the switch is pushed.” This
relation between the event like “the switch is pushed” andthe action like “turn on the light” is actually the relation between an EN’s ANTH address and a SN’s ANTH address.
Therefore, real-space programming is realized by rewriting
ANTH addresses by a controller. The controller’s operations of rewriting ANTH addresses are constructed by combinations of getting or setting EN or SN’s ANTH addresses.
The combinations can be depicted as following three operations.
Operation 1

Get an EN’s ANTH address and set it to a SN.
This operation describes a fundamental relation like “turn on
the light if the switch is pushed.” This is a standard operationof relation description.
Operation 2

Get a SN’s ANTH address and set it to another SN.
Suppose that a user wants to add the relation “ring the bellof the alarm clock if the switch is pushed” after descriptionoperation of the above Operation 1. In this case, it is realizable by copying the ANTH address from the SN which can
do “turn on a light” to the SN which can do “ring the bellof an alarm clock.” This operation is valid when we want torelate two or more SNs with an EN as a group.

Operation 3

Get an EN’s ANTH address and set it to another EN.
Suppose that a user wants to change the relation from “turnon the light if the switch is pushed” to “turn on the light
if the alarm clock rings” after description operation of theabove Operation 1. In this case, it is realizable by copying
the ANTH address from the EN which emits the event “theswitch is pushed” to the EN which emits the event “the alarmclock timer expires”. Moreover, it is possible to erase theoriginal relation by setting a new ANTH address to the EN
which has the event “the switch is pushed.” This operation
is valid when we want to reconstruct the relations efficiently.
As mentioned above, this Bind Control Model enables us tobriefly describe user demands like “want to create service
by connecting this object and that object” in the abstractedform.
PROTOTYPE IMPLEMENTATIONThe ANTH specifies from hardware to user interface. However, the Bind Control Model does not depend on hardware
platforms because it is just a part of the ANTH framework
and a software mechanism. The Bind Control Model is, additionally, designed to run on tightly limited computing resource. Thus, the Bind Control Model can probably be realized on Smart-Its[1] or MICA[2] hardware platform. Since
this prototype implementation is aimed to just check operations of the Bind Control Model and we are very familiar
with U3 [3], we have implemented the Bind Control Modelon U3 .
Figure 2 shows 4 implemented ANTH objects: a light, analarm clock, a button, and a U3 which is wireless sensor node.
The light and the alarm clock bell work as SNs, the alarm
clock timer, the motion sensor of U 3 , and the button work asENs, and laptop acts as a controller. We have tested the basic
operation of the Bind Control Model using these four typesof nodes. For example, the motion sensor event bounded tothe alarm clock bell realizes instant security system, whichtells us intrusion of someone by ringing the bell.
CONCLUSION AND FUTURE WORKThis paper has described the Bind Control Model and prototype implementation of a real-space programming framework called ANTH (ANtennary THings) for ubiquitous computing environment. Currently, we are developing user-friendly
user interface for device cooperation as a controller. And, inview of practical use of ANTH, we are also developing communication protocol that concerns low power consumption.
REFERENCES

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Button[2] J. Hill et al., “Mica: A wireless platform for deeply
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LightU3

Figure 2: Prototype implementation[3] S. SARUWATARI, et al., “Pavenet: A hardware andsoftware framework for wireless sensor networks,”
Proceedings of the First International Workshop on
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