This document proposes a system called CareTwitter that uses NFC and RFID tags to improve data management in elderly care centers. RFID tags are used as portable databases to store care logs for each resident. When a staff member interacts with a resident's RFID wristband using an NFC mobile phone, the care log is updated on the tag. CareTwitter also exports care logs to Twitter to keep friends and family updated on residents' daily activities. The system aims to enhance data gathering and sharing in challenging care center environments.

1. Twitting Care Events: Assessing the Data-on-Tag approach in NFC-supported AAL Diego López-de-Ipiña+, Ignacio Díaz-de-Sarralde+, and José Bravo* +Facultad de Ingeniería & Tecnológico Fundación Deusto, Universidad de Deusto, Avda. Universidades 24, 48007, Bilbao, SPAIN *MAmIResearchLab, Universidad de Castilla La Mancha, Ciudad Real, SPAIN {dipina, isarralde}@deusto.es, Jose.Bravo@uclm.es

2. Contents Introduction Objectives & Features Related Work RFID tags as portable databases An NFC-supported platform Posting AAL care logs to Twitter Conclusion

3. Introduction Technology: RFID is mainly used to uniquely identify objects However, passive HF RFID tags allow significant data storage (up to 4K) RFID technology is proving as a key enabler of Internet of Things (IoT) The RFID data-on-tag approach makes immediate access to touched or pointed object’s Domain: AAL aims to increase our quality of life and autonomy and to reduce the need for being institutionalised or aiding it when it happens Elderly care centres are challenging environments from the data gathering and publishing perspective. Solution: NFC technology + RFID data on tag in order to gather lifelogs of residents and publish them BOTH on the intranet and Internet

4. Objectives This work has a two-fold objective: Experimental: Evaluate how much data can actually be stored in HF RFID tags Practical: Combine the RFID data-on-tag approach with NFC to improve data management in a care centre, where: RFID tags can serve as temporary repositories of care events Interactions between residents’ RFID wristbands and staff’s NFC mobiles can improve care data management and keep relatives up-to-date

5. Related Work NFC technology operating on 13.56MHz combines the functionality of a RFID reader device and a RFID transponder into one integrated circuit NFC read/write mode allows NFC devices to access data from an object with an embedded RFID tag The combination of NFC technology and RFID tags has been used in the last few years in several research projects related to medicine and caretaking However, so far RFID applications have not incorporated custom data directly onto RFID tags Still prevails a generic lack of standardization, only alleviated by initiatives such as the Continua Health Alliance

6. CareTwitter Features Supports caretaker on structured patient data recollection and storage Allows collected data to be used efficiently By enabling easy and clean data writing and reading of RFID tags with NFC phones By relying patient activity to relatives via Twitter Research novel RFID applications in daily use Uses HF RFID tags as embeddable and portable DB Proposes optimal data encoding and compression

7. RFID Tags as Portable Databases The NFC Forum specifies a data-packaging format called NDEF (NFC Data Exchange Format) to exchange information between an NFC device and another NFC device or an NFC tag Evaluation of HF RFID tags as tools to store data: Select a set of easily wearable tags (ISO 15693-compatible) with as much storage capacity as possible and still compatible with NFC Identify the maximum number of useful bytes storable in the selected tags Develop a new efficient mechanism to store data on HF RFID tags 7

8. Storage Capabilities of a 4K Mifare Watch

9. Efficient Recording of Data in HF RFID Tags Analysing evaluating data, it was decided that only one record NDEF messages should be used No standard on the data structures used by care centres to keep data on their interns was found Therefore, we have developed our data structures and encoding mechanisms: A Range Encoding Compression of previously encoded and serialized messages is proposed.

10. A Platform to Enhance Care Data Management Caretaking is a suitable domain for combining NFC technology and the RFID data-on-tag approach in order to enhance the data gathering process Elderly people are looked after at different domains (elderly people’s homes or their families’, the residence itself) and by different people (relatives or residence staff), making very difficult to reconcile the information gathered Some issues: Residents do not always stay and sleep at the care centre Data capture is not highly prioritised IT support at care centres and family homes is diverse

11. Analysis of Data Collected in Caretaking

13. Assists the caretaker in the data gathering process

14. Allows for anywhere at any time multi-user gathering of data

15. Allows for asynchronous care data reporting

17. CareTwitter proposes a special purpose compressed serialization method in order to maximize the usage of HF RFID tags’ storage: Stringified – human readable string. E.g. 2009/10/08T09:57:00:35609912 @Home:Woke Up Encoded – transformation of a stringified care log into a more optimal representation. E.g. 35609912#2##1254988620907#4 Serialized encoded – it is a byte representation of a care log Compressed serialized encoded – applies to it the Range Encoding compression algorithm CareTwitter Care Log Encoding

18. Care Data Encoding Classes

19. CareTwitter Care Log Encoding

20. Populating Twitter with Care Logs The CareTwitter AAL platform does not only keep custom data to enhance the daily activities in a care centre but ... It also exports part of that data to the external Twitter micro-blogging service from which relatives and friends can follow the lifelog of residents

21. CareTwitter @ Work

22. Conclusion CareTwitter stores a log for every new care procedure applied on the resident’s RFID wristband, following a data-on-tag approach It uses RFID tags as mini databases CareTwitter makes data stay at any time with the resident and be available in real-time and without relying on wireless links Our experiments show that the storage capacity of 1K (wristband) or 4K (watch) Mifare RFID tags, aided by CareTwitter’s custom-built compressed serialized encoded data serialization format, is sufficient for storing the care logs of a whole day The integration of CareTwitter with Twitter proves the high potential of using interactions with everyday objects or people to automatically publish data into Internet In this case, the lifelog of a resident is available to authorized users