InfoPulse: a Wrist­worn Ambient Display Eric Migicovsky Systems Design Engineering University of Waterloo Waterloo, ON N2L 3G1 Canada +1 519 721 6700 emigicov@engmail.uwaterloo.ca ABSTRACT music track while biking down a busy street or even This report describes the design process behind the something as simple as checking email while in the midst creation of the InfoPulse, an innovative smartphone of a phone conversation. For voice calls, Bluetooth accessory. The InfoPulse is an ambient information display headsets address some factors but offer no way of designed into the form factor of a standard wristwatch. accessing the vast amount of text information that is Connected wirelessly to nearby smartphone, it receives available on modern smartphones. This project endeavours and discreetly displays important information, like recently to design a similar device to enable mobile text display, received text messages, emails and calendar alerts, to the creating a 'Bluetooth headset for email and SMS,' user. Designed to function without interaction from the positioned as a companion piece of hardware to a user, the InfoPulse acts as a handsfree email reading smartphone. device, perfect to catch a quick glance without distracting too much from a user's primary task. The process The idea was initially influenced by a fairly common culminates with the development of a physical prototype problem experienced by those who bicycle often on busy that demonstrates proof-of-concept functionality. car-heavy streets. Normally when your cell phone rings or vibrates, it is trivial to reach down and answer the alert. Keywords But in a high pressure and potentially unsafe environment, Ambient information system, smartphones, ubiquitous one cannot spare the limb and attention necessary to computing, displays, wireless communication. execute this manoeuvre. This problem is amplified by visually complex operating systems (OS) or difficult one- INTRODUCTION handed operation on the smartphone itself. After Smart mobile devices, common examples being the RIM discussing the problem with several bicycle and mobile Blackberry, Apple iPhone and Nokia n95, offer users phone users, it was clear that safety would be greatly connectivity and communication options that were unheard improved by providing these users with an alternative of in previous generations of mobile phones. Offering the means of monitoring incoming calls, SMS and email. addictive lure of constant email and IM access, smartphones are found consistently in the pockets of Users in other situations could also benefit from a similar students, business people, commuters and those with an solution. For those who move around constantly affinity for new gadgets. As useful as they are, throughout the day, a smartphone is sometimes the only smartphones are usually quite large, bulky and heavy. tool that enables them to keep in touch with the external world. Therefore, in business meetings it is common to The increasing proliferation of smartphones poses several hear the buzz of a smartphone, indicating an incoming problems that are becoming more evident. The normal use email, followed by the user immediately pulling out the of these devices in everyday situations may present a device to check the display. This action comes almost as a safety hazard, a distraction from a primary task or simply second nature to the habitual Blackberry user and usually an inconvenience. Through an analysis of these flaws, presents quite a distraction to the remainder of the group several areas for improvement were found. The design members. This problem is caused by the limited process was used to determine the best course of action information conveyed by initial vibration of the needed to overcome these deficiencies. smartphone. The binary indicator does not allow the user to make the distinction between an important time MOTIVATION sensitive SMS and intra-office forwarded email. In the mobile device arena, multi-tasking entails juggling between separate physical tasks, like checking caller ID Allowing the user to make a more informed time- before answering a phone call while driving, changing a management decision is one of the basic benefits that this sort of device could offer. These simple scenarios Copyright © 2008 for the individual papers by the papers' demonstrate particular ways in which a smartphone authors. Copying permitted for private and academic companion display would help, but in essence any existing purposes. Re-publication of material from this volume smartphone user in a position where it is inconvenient to requires permission by the copyright owners. use their phone traditionally would benefit from this device. • Eliminate the need for the user to repetitively check EXISTING SOLUTIONS or interact with their smartphone by allowing Over the last few years, sales of smartphones have greatly information to pass ambiently (without user increased within the general mobile market. While intervention) from the smartphone to the user. Blackberry by RIM was one of the first to allow constant • Minimize any interference with regular activity by email access in a mobile form-factor, this feature is now ensuring that any body worn device is slim and common on all smartphones. Previously only found unobtrusive. hanging on the belts of busy business men rushing through • Able to connect wirelessly to a nearby smartphone a downtown core, email capable devices are being snapped to receive data streams. up by office-less workers, commuters, students and • Software running on the smartphone must be frequent travelers. It is estimated that over 116 million capable of prioritizing and filtering data sent to the smartphones were sold in 2007 [1]. The capability for device based on importance, keeping in line with ubiquitous computing, through these increasingly capable the functionality requirement to limit user mobile computing platforms, has finally reached the distraction. mainstream. Concept generation In the past, several attempts were proposed (and some In order for the display to be available to the user at any executed) to realize a system of body-worn mobile devices given time, the device must take on a form that the user designed to deliver information more directly to the user. could carry or wear at all times. As it has been made clear Computer science students at the University of South in the above sections, the form factor of a watch has Australia developed a prototype of a simple liquid crystal always been seen as the main option. There were several display (LCD) powered watch that was capable of reasons for this choice. From an efficiency standpoint, displaying the output for several different applications [2]. watches are accessible by the user without any particular It connects by Bluetooth to a 'Personal Server' or PerServ, physical interaction, allowing for hands-free operation. a separate personal digital assistant (PDA) that would in Watches are already an accepted article of wardrobe, turn be connected to the internet by WiFi. though currently observed to be declining in popularity [5]. Other research explores mobile personal data servers lacking input or output mechanisms but capable of The purpose of this device is not to replace the large, high- wirelessly 'hijacking' nearby displays and keyboards. Intel resolution, colour screen of a smartphone but to Research developed a prototype of a lightweight portable complement it by providing an alternate text display server, the size of a deck of cards, designed to store all of location. Several screen technologies were applicable the users computer files like email, documents, music and including monochrome graphical liquid crystal displays video [3]. It was designed to wirelessly serve these data to (LCD) and organic light-emitting diodes (OLED). LCDs local screens or computers that the user was close to, are robust, affordable and easy to work with. Many small- eliminating the need to carry a bulky laptop but preserving scale electronics companies offer wide varieties of choices: the security and privacy that comes with the ability to black/white to colour, resolution, refresh rate, power physically guard data. consumption. Disadvantages particularly relevant to this application revolved around power consumption: LCDs In the general market, only a few products have emerged work by modulating light that passes through the screen, which offer more personal and efficient access to mobile so a backlight is needed to illuminate the screen in low- data. Fossil designed a companion watch for Sony Ericsson light conditions. A relatively new entry into the field of mobile phones in 2005 [4]. The second revision of the mobile screens are OLED displays. These displays are product line, the astutely named MBW-150 watch, inherently more power efficient because light is created connects over Bluetooth to a nearby mobile phone and within the display by efficient LEDs, eliminating the need shows an alert right on the watch face when an SMS or for a backlight. Unfortunately, OLED technology is still incoming call is received. According to specifications, this quite expensive, with rough estimates of small 1.5” product should be able to function for up to 7 days on one screens being triple the price of a similar LCD [5]. For charge. prototyping purposes, the choice was made to select a low- cost monochrome LCD screen, that could coincidentally be DEVICE salvaged from the extraordinarily common Nokia 3310 cell A prototype device was developed to determine if the phone. This screen draws only 1mA, though does not problems addressed above could be solved by a new include a backlight. device. User input on a device as small as a watch is very difficult. Requirements Existing solutions, like wristwatches themselves, rarely • Increase user awareness of data being received by include many user adjustable features simply because it is their smartphone by providing the user with real difficult to provide a clear and user friendly method of time access to information such as: incoming caller interacting with such a small device. The calculator watch ID, SMS, email and music track information. is a typical example. Acting upon Gaber's [6] principle of pervasive computing, which describes spontaneous Prototype networks created between devices intent on sharing The prototype was assembled through a period of several available services and computing power, the device should months at TU Delft. Since cost and availability were be able to leverage the fact that it is connected to a more considered during design selection, most components were powerful input/output service (the smartphone). Inputs easy to buy from online electronic component suppliers.. must be limited to yes/no confirmations and other simple Components were integrated together on a breadboard choices. Implementations like the 'magic' button on the while Arduino software was written to allow the Nokia Apple iPhone microphone-headphone demonstrates how a 3310 screen to interface with the microcontroller. After simple binary input can be multiplexed to serve several successfully testing the design on the breadboard, the different functions depending on the current application in design was implemented on a printed circuit board (PCB). use. Figures 1 shows the prototype in it's current form. Several competing standards were available in terms of low power, short range (<3m) wireless communication. The Bluetooth standard was by far the most well known. Implemented in millions of devices worldwide, from cell phones to cars, it connects devices together spontaneously to share information. Unfortunately it depends on a larger power source than possible for a constantly communicating watch application. A standard Bluetooth Philips BGW203 Bluetooth module consumes at a minimum 8 mA in active mode [7]. To get around this consumption problem, other low power sensor applications like the Nike+ running activity monitoring system, take advantage of the Nordic line of radio frequency (RF) transceivers [8]. Nike designed a special interface dongle to receive data from their shoe sensor and relay it to an iPod. The Nordic sensor uses fractions of the power of a Bluetooth module since it is designed for much shorter distances. The design here somewhat mimics the setup of the Nike+ system: the watch will have a Nordic wireless transceiver built in while a separate dongle will be designed to plug into Fig. 1 Photo of the completed prototype in music various smartphones to receive the signal. track mode To keep the whole system running together, a CONCLUSION microcontroller interfaced between all subsystems. There The prototype presents a proof-of-concept version of a are a multitude of microcontroller options and the basic wrist-mounted ambient information display. Looking at requirements for low-power, size, weight, connectivity did the physical prototype, it is possible to see how this sort of not help to limit the options down too far. In lieu of a design could be adopted by users. It presents information strong reasoning, a familiar option was selected: the in a readily available format, giving users quick access to ATmega 168 chipset within the open-source Arduino data that would otherwise be accessible solely on a environment. The Arduino is easy to program in C and has smartphone screen. The display is capable of playing back a large public following online, offering many avenues for preset example messages but currently lacks smartphone support. Since the Arduino has published printed circuit side software to relay messages in real time. board (PCB) and schematics drawings available online, it is very easy to integrate it into a custom design. The future of technology in this sector rapidly shifts. Since the tech specs were locked down for prototyping back in Several competing battery technologies (nickel-metal June, equipment manufacturers have already released hydride, lithium-ion and lithium-ion polymer) are revisions of components in the design. Longer term plans available small applications. Lithium-ion (Li-ion) from the Bluetooth Special Interest Group (SIG) towards currently represents the most efficient form of energy Ultra-low Power (ULP) Bluetooth now appear to be much storage, in terms of energy density or Watt-hours per more relevant, especially if new smartphones released in kilogram, for a mobile device of this size. Li-ion's close 2009 begin to offer this connectivity option [9]. cousin, lithium-ion polymer, has a similar chemistry but is slightly cheaper. Li-poly batteries are currently used in ACKNOWLEDGMENTS many mobile applications like cellphones and cameras. A I would like to specially thank the Studio Lab staff from 3 gram, 100mAh li-poly battery was selected for this the IO Faculty at TU Delft. Rob Luxen, in particular, application. provided excellent advice and access to tools. REFERENCES 5. “Graphic OLED Color Display 128x128.” 1. Canalsys Worldwide converged smart mobile devices http://www.sparkfun.com/commerce/product_info.php? market research report. Available at products_id=712. http://www.canalys.com/pr/2008/r2008021.htm. 6. M. Bakhouya and J. Gaber, “A Propitient Multi-agent 2. P. Hutterer, M. Smith, B. Thomas, W. Piekarski, and J. System for Spontaneous Service Emergence in Pervasive Ankcorn, “Lightweight user interfaces for watch based Computing environments,” Pervasive Services, IEEE displays,” Proceedings of the Sixth Australasian International Conference on, pp. 409–414, 2007. conference on User interface-Volume 40, pp. 89–98, 7. “BGB203 Datasheet V1.0.” 2005. www.futureelectronics.com/europe/promos/nxp/Bluetoot 3. R. Want, T. Pering, G. Danneels, M. Kumar, M. h/docs/BGB203_ShortDatasheet_V1_0.pdf Sundar, and J. Light, “The Personal Server: Changing 8. “Nike+iPod Dissection.” the Way We Think About Ubiquitous Computing,” http://www.sparkfun.com/commerce/tutorial_info.php? LECTURE NOTES IN COMPUTER SCIENCE, pp. tutorials_id=41 194–209, 2002. 9. “Bluetooth Low Energy Technology.” 4. Sony Ericsson Bluetooth Watch MBW-150. http://www.bluetooth.com/Bluetooth/Products/Low_Ener https://fjallfoss.fcc.gov/prod/oet/forms/blobs/retrieve.cgi? gy.htm. attachment_id=837724&native_or_pdf=pdf.