Smart Furoshiki: A Context Sensible Cloth forSupporting Everyday Activities

Ryo Ohsawa, Kei Suzuki, Takuya Imaeda, Masayuki Iwai,Kazunori Takashio, and Hideyuki Tokuda

Keio University, Graduate School of Media and Governance,5322 Endo, Fujisawa, Kanagawa, 252-8520 JAPAN

{ryo,suzuk,che,tailor,kaz,hxt}@ht.sfc.keio.ac.jp

http://smart-furoshiki.com/

Key words: Furoshiki, Smart Cloth, RFID, Context Awareness

1 Introduction

This paper introduces a novel system for supporting everyday activities. Recentresearches have proposed the embedding of computers and sensors in user en-vironments so as to provide assistance in certain scenarios [1]. However, it isdifficult for users to make the environments. Our goal is to develop a technol-ogy that will enable novice users to create such environments easily. In order toachieve this goal, we have developed a sensorized cloth called “Smart Furoshiki.”

Fig. 1. Furoshiki: Japanese Traditional Wrapping Cloth [2]

Furoshiki, which is a type of traditional Japanese cloth used to wrap mer-chandise, is large, square-shaped, and flexible. It is also used as a tablecloth andas a cloth to cover or wrap different objects. The Smart Furoshiki can identifyobjects that are covered by it or placed on it and recognize user actions such aswrapping, covering, and bending. Based on these user contexts, applications canassist users. Researches aimed at realizing a smart carpet or smart tablecloththat is capable of identifying objects placed on it have been conducted in thepast [3] [4]. The Smart Furoshiki, in comparison to the abovementioned cloths,

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can change its shape with greater flexibility. Therefore, users can use the SmartFuroshiki both as a carpet and as a tablecloth.

2 Concept: A Context Sensitive Cloth

1. 2. 3.

Fig. 2. An example of furoshiki’s usage [2]

An advantage of furoshiki is its ability in assisting in the wrapping of variousobjects such as a box, bottle, fruit, etc. The method employed for wrapping abox with a furoshiki is shown in Fig.2. Further, a furoshiki is also used as a tablecloth, cover, etc. The Smart Furoshiki concept involves obtaining user contextsand providing support in daily life. In order to obtain user contexts, the SmartFuroshiki can detect a user’s operations on it and identify objects placed on it.

3 Method

RF Reader and Battery

Antenna

Bluetooth

Fig. 3. The prototype of Smart Furoshiki

The prototype of the Smart Furoshiki is shown in Fig.3. The antenna ofthe Smart Furoshiki is made of conductive fabrics [5] so that it can be bent ina flexible manner. The antenna connects an RF reader with a battery. The RF

Smart Furoshiki 3

reader also has a Bluetooth module to enable it to communicate with appliances.The Smart Furoshiki has two features. One is that it can identify objects thatare placed on it or are covered by it. The other feature is its ability to recognizehuman actions such as wrapping, covering, and bending. The surface of the SmartFuroshiki can recognize RFID tags, thereby enabling it to identify objects placedon it.

Ant1 Ant2

Tag1

Ant3

Tag3

Ant4

Tag4Tag2

Ant5 Ant6 Ant7 Ant8

Tag5 Tag7 Tag8Tag6

Fig. 4. The Smart Furoshiki contains eight embedded RFID antennas and iscapable of recognizing its own shape

This prototype contains eight embedded RFID antennas (Fig.4), and it canrecognize 13.56 MHz passive RFID tags. The RFID reader uses the eight an-tennas based on a timesharing system in order to prevent radio wave collisionsbetween the antennas. The reading distance ranges from 0 to 180 mm accord-ing to the tag size. Since the Smart Furoshiki uses 13.56 MHz radio frequency,it is influenced by metals. Therefore, the range of the Smart Furoshiki wouldchange depending on the environment that it is located in. In order to solvethis problem, a calibration algorithm was implemented in the Smart Furoshiki.Furoshiki is used for various purposes. The Smart Furoshiki can recognize useractions such as laying, covering, and hanging. In order to detect these actions,the Smart Furoshiki should be capable of recognizing its own shape. In our ap-proach, tiny RFID tags are embedded in the Smart Furoshiki. The image on theleft of Fig.4 shows the antenna and tag layout of the Smart Furoshiki. Accordingto this image, antenna 1 usually reads tag 1. However, if the Smart Furoshikiis folded, as shown in the image on the right, antenna 1 reads tag 4, therebyrecognizing its folded form.

4 Applications

This section discusses the effectiveness of the proposed system in actual appli-cations supporting daily activities; some examples are depicted by the images

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in Fig.5. We start off by explaining three applications. Each application detectsdifferent user actions and the shape of the Smart Furoshiki in each of them isdifferent. We assume that objects of everyday use are attached with RFID tagsso that the Smart Furoshiki can detect their presence.

3 4

21

Fig. 5. 1: Smart Desk, 2: Security Cover, 3: Smart Wrapping, 4: Smart Wall

4.1 Smart Desk

Smart Desk is a desk covered with the Smart Furoshiki. In one application of thisdesk, the Smart Furoshiki supports collaboration between media and actuatorsplaced on it (the image one in Fig.5). When a user wishes to watch a movie on aPDA, he/she places the PDA as well as a DVD media, positioned near the PDA,on the Smart Furoshiki. In this application, the PDA is able to detect the DVDmedia and play the corresponding media content. In another application, whena user leaves his/her work desk and covers objects placed on the desk with theSmart Furoshiki, he/she can lock the objects to prevent other people from usingthem (the image two in Fig.5). If an unauthorized person uncovers the SmartFuroshiki, a security system immediately sets off an alarm. In order to uncoverthe Smart Furoshiki, the user’s identifying object must be placed on it.

Smart Furoshiki 5

4.2 Smart Wrapping

Since the Furoshiki is essentially used for wrapping objects, the Smart Furoshikiis equipped to recognize wrapped objects and their shape. Nowadays, sensorRFID tags are equipped with additional devices to aid vendors; for instance,RFID tags could be equipped with an acceleration sensor [6] or a temperaturesensor [7]. When such tags are embedded in the Smart Furoshiki, the user isable to determine the characteristics of the wrapped object (the image threein Fig.5). For example, if a user wishes to carry a bottle of wine wrapped inthe Smart Furoshiki, he/she will be able to determine the characteristics of thebottle and therefore, handle it with care.

4.3 Smart Wall

Another useful application can be realized by hanging the Smart Furoshiki on awall, like tapestry (the image four in Fig.5). In an office, people often pin memoson the wall in order to remember them easily. In this application, when a userwrites a memo with an electronic pen [8] and pins it on a Smart Furoshiki hungon the wall, the memo appears on a PC or a mobile device. In Fig.5, the SmartFuroshiki is separated into 4 areas based on the priority of the task, such as“Emergency task” and “Pending task.”

4.4 Historical Data Analysis

In order to determine user context from historical data, we use a middlewarecalled “OreDesk [9].” OreDesk calculates the “relation index” and “active index”values for each object based on user operations. The relation index indicateshow closely one object is related to another. For conveying the relation index,the Smart Furoshiki reminds users about objects left behind on it. The activeindex indicates a user’s interest in an object. For conveying the active index, theSmart Furoshiki extracts a user’s preference from his/her daily behavior in thereal world.

5 Experiments

We have conducted two experiments on the Smart Furoshiki prototype. First,in order to evaluate its basic performance, its sensing area is measured in threedimensions. Second, we have conducted a feasibility test in typical scenarios.

5.1 Sensing Area Measurement

The result of a measurement is shown in Fig.6. The left image of the figureindicates a horizontal sensing area. The blue line indicates an antenna embeddedinto the Smart Furoshiki. The antenna, which is a 200× 200 (mm2) square, canidentify the RFID tag that is placed on an orange area. In the case when an

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80 mm

200 mm120 mm 120 mm

120 mm

150 mm

50 mm

200 mm 120 mm120 mm

A B

A B

Fig. 6. Left: Horizontal Sensing Area; Right: Vertical Sensing Area

antenna is in the neighborhood of another one, the sensing area is more spreadon account of electromagnetic induction. In the case of the figure, the right, left,and front areas are more spread than the back area.

The right image in Fig.6 is a vertical sensing area extending from A to Bin the left image. The center of an antenna has the largest sensing area. Onaccount of electromagnetic induction, the sensing area is widely spread acrossthe antenna line.

5.2 Feasibility Test in Typical Scenarios

We have conducted a feasibility test in typical scenarios. In one scenario, userslay the Smart Furoshiki on an office desk. In another one, the Smart Furoshiki isused on a dining table. We selected objects that are often used in these situationsand experimented to ascertain which objects the Smart Furoshiki can recognize.We used a square 45 × 76 mm2 Tag-it RFID tag that is shaped like a businesscard [10]. We attached these tags both above and under an object. In order toattach them to metal materials, On-Metal tags were prepared. The results ofour experiments are shown in Table 1. The 13.56 MHz radio signal that theSmart Furoshiki emits is strongly influenced by aluminum and metal materials.Using the On-Metal Tag, the influence on the Smart Furoshiki by such materialsbecomes negligible. However, when a large metal object such as a PC and adisplay covers an object, the Smart Furoshiki cannot recognize it.

6 Future Work

The Smart Furoshiki prototype that we proposed should enable connecting anRF reader, which is too big for users to carry easily. We are developing thenext Smart Furoshiki version. A tiny RF reader and a small li-ion battery areembedded in it. This will make it portable.

Smart Furoshiki 7

Table 1. Sensing accuracy of the objects

Office Desk

Laptop PC Display PDA Cell Phone Keyboard DVD Book Wallet Mirror

Under × × × × © © © © ©Under (On-Metal Tag) × × © © © © © © ©Above × × × × © © © © ©

Dining Table

Plate Drink Package

Ceramic Wooden GlassBottle Can

Plastic AluminumPET Glass Steel Aluminum

Under © © © © © × × © ×Under (On-Metal Tag) © © © © © © © © ©Above © © © © © × × © ×

7 Conclusion

We have developed a Smart Furoshiki prototype and have implemented manyapplications that assist users. This study describes the experimentation with thisSmart Furoshiki prototype.

References

1. Christian Muller-Tomfelde Shin’ichi Konomi Norbert Streitz, Peter Tandler.Roomware: Towards the next generation of human-computer interaction basedon an integrated design of real and virtual worlds. In J. Carroll, editor, Human-Computer Interaction in the New Millenium, pages 553–578. Addison-Wesley.

2. Japan furoshiki association. http://furoshiki.homepage.jp/.3. Masaaki Fukumoto and Mitsuru Shinagawa. Carpetlan: A novel indoor wireless(-

like) networking and positioning system. In Ubicomp, pages 1–18, 2005.4. E. R. Post, M. Orth, P. R. Russo, and N. Gershenfeld. E-broidery: design and

fabrication of textile-based computing. IBM Syst. J., 39(3-4):840–860, 2000.5. Masato Tanaka and Jae-Hyeuk Jang. Wearable microstrip antenna for satellite

communications. IEICE Transaction on Communications, August 2004.6. OMRON Corporation. http://www.omron.co.jp/.7. Ltd Oki Electric Industry Co. http://www.oki.com/jp/Home/JIS/New/OKI-

News/2006/04/z06005.html.8. Pentel. Pentel airpen. http://www.airpen.jp/.9. Ryo Ohsawa, Kazunori Takashio, and Hideyuki Tokuda. Oredesk: A tool for re-

trieving history data based on user’s operations. In Proceedings of IEEE Interna-tional Symposium on Multimedia 2006 (ISM2006), 12 2006.

10. Texas Instruments Inc. Tag-it. http://www.ti.com/.