Design of a Smart Fitness Watch: Promoting Healthy Living for the Visually Impaired Unwana Michael Umoren David Ho Simon Connolly University of Bath University of Bath University of Bath United Kingdom United Kingdom United Kingdom [email protected] [email protected] [email protected] Group 4 Group 4 Group 4

ABSTRACT impaired) are most likely to be less physically active than Physical activity plays a vital role in promoting healthy those without disabilities [9]. As a result of their less activity, living. Deficiency in physical activity increases vulnerability there are more susceptible to chronic diseases [9]. This to chronic diseases (such as cancer, obesity, etc. and reduced physical activity in visually impaired people is usually leads to a high rate of mortality. Physical inactivity is posed by barriers such as: reliance on other people exercise particularly common amongst the visually impaired than the assistance, transportation to the place of exercise and limited visually unimpaired. The visually impaired having decreased or no options available [8]. participation in physical activity due to certain barriers such This paper presents a prototype of a smart braille fitness as cost, transportation, etc, are prone to chronic diseases and watch for the visually impaired. The smartwatch aims at death in critical cases. To eliminate the barriers to physical promoting healthy living by increasing the physical activity activity experienced by visually impaired people, a prototype of visually impaired people. It employs the braille and audio of a smart braille fitness watch was designed. This paper technology to interact with the visually impaired user. The presents qualitative research using a case study of a visually allows the user to interact with the watch impaired undergraduate student Susie. The smart fitness while the displays/actions on the screen are being read aloud to braille watch was specifically designed following Susie’s the user. Also, health information such as the number of steps specifications. It uses braille technology and accepts voice taken per day, calories burnt and heart rates are fed back to the inputs from the user. Information such as time of the day, user. In the event of inactivity, a reminder is sent to the user to number of steps taken, heart rate and calories burnt are sent carry out tasks such as walking, running, etc., thus reducing the back to the user. Health reminders in the event of inactivity physical inactivity in visually impaired people. This research is also a functionality present in the watch to monitor and seeks to proffer solutions to the challenge of physical inactivity promote physical activity. This prototype was tested by Susie experienced by visually impaired individuals by removing the and feedback showed that it increased her level of physical barrier of cost, transportation and information retrieval. activity than in the past. Therefore, this research provides a solution to the physical inactivity experienced by visually impaired people. BACKGROUND According to the World Health Organization (WHO), statistics Author Keywords as of 2018 show that at least 2.2 billion people globally are Physical activity, healthy living, smart braille fitness watch, visually impaired [18]. Numerous studies have also shown visually impaired, prototype. that deficiency in the physical activities by visually impaired individuals impacts their quality of life [10]. With vision INTRODUCTION being extremely important for performance of daily activities Physical activity is one of the most important aspects of [3], physical activity is difficult to carry out when visually healthy living [13]. National Health Services (NHS) in the impaired [12]. physical activity guideline recommends that regular physical Studies by Haegele et al demonstrates that people living activity (at least 150 minutes of moderate intensity activity with disabilities are less physically active than those living or 75 minutes of vigorous intensity activity a week) should without disabilities [9,2]. This research explores reasons be carried out by adults (abled and disabled) between the why individuals living with visual impairments may or may ages of 19 to 64 to improve their overall health [11]. Regular not engage in physical activities. It provides theoretical participation in physical activities promotes both physiological determinants of physical activity and sedentary behaviours in and psychological health [10]. Lack of physical activity poses visually impaired and analyses their beliefs about engagement risk of cardiovascular diseases and chronic diseases such as in physical activity. diabetes, cancer, obesity, bone/joint diseases and depression [17]. Research shows that individuals who engage in regular Carroll et al, explains that half of individuals living with physical activity are less likely to suffer from health-related disabilities are physically inactive and 50 percent are prone issues than those who are not [8]. Further researches show to chronic diseases as a result of physical inactivity [5]. The that people living with disabilities (especially the visually results of this research showed that physical inactivity was on

1 the high side among those living with disabilities than those as sound and touch) and braille for communication. In order living without disabilities with case study of United States. to navigate to the campus and other places, she uses a guide This confirms Haegele et al’s research on the beliefs about dog. She uses the screen reader to access her phone and laptop. physical activity and sedentary behaviors of adults with visual From the several interviews conducted with the participant, her impairments. major challenge is engaging in physical activity due to certain barriers which are: Transportation, cost and information Starkoff et al proves that visually impaired people spend more retrieval. With Susie’s pain points as a case study, the smart time engaging in sedentary activities (activities involving braille fitness watch was designed to solve the problem of seating) than physical activities such as: walking, running, physical inactivity faced by Susie as a result of being visually etc. [15]. The descriptive study identifies sedentary trends impaired. In order to better understand Susie’s problem, in individuals with visual impairments with the goal of not interviews were conducted. only improving their quality of life through physical activity but minimise the negative impacts of prolonged involvements Interview/ Discussion of Current Solutions in sedentary activities. This research proves that visually This interview aimed to get a better understanding of the impaired individuals engage less in physical activity and more physical activity problems Susie encountered. The session in sedentary activities which hampers their health and overall lasted for about 30 minutes. A questionnaire was read out to quality of life. Susie and the answers were documented. From this session, Susie pointed out several barriers to engaging in physical Psychometric Study conducted by Ellen Armstrong et al on 41 activity which included: transportation to the gyms which are children living with visual impairments in USA showed these far off, employing a personal trainer was quite expensive for children had low physical activity as a result of the barriers her, she prefers her own space when it comes to exercise, not encountered as a result of being visually impaired [2]. being able to gain access to the right kind of exercise and Reports by the Centre for Disease Control and Prevention finally not being able to use the current solutions. The current USA (CDC) in 2010 show that visually impaired people are solutions Susie has and her feedback on them are as follows: at a higher risk of developing health problem due to their sedentary lifestyle [7]. This further proves the effect of Susie’s Current Solutions to Physical Inactivity and Major physical inactivity has on the visually impaired. Drawbacks 1. Fitbit: Fitbit is a smart fitness watch that enables users to Comparative study performed by Dorota Sadowska et el reach their health and fitness goals by tracking their activity, between sighted and visually impaired showed that individuals exercise, sleep, weight, heart rate, calories and more. Susie with sights took more steps (more physically active) while owns a Fitbit which she finds difficult to use because being visually impaired people took less steps which shows their visually impaired she encounters difficulty in navigating physical inactivity [14]. through the various screens and accessing the functionalities. A HUNT study carried out by Audun Brunes et al on the The Fitbit’s operation is solely tied to the phone which she effect of lack of physical activity on high mortality in visually finds very inconvenient to use. With all these pain points impaired individuals showed that visually impaired people faced by Susie, she concludes that although Fitbit is a good constituted to the high mortality rates as a result of deficient solution it doesn’t work so well for her thus increasing her physical activity [4]. level of physical inactivity. The above selected researches prove that visually impaired 2. Smart Dotwatch: The smart dot watch is a smartwatch individuals are physically inactive and this poses serious health that uses the braille technology to tell time, manage calls threats such as chronic diseases and worst death. This calls for and messages, provide social media notifications and set concern because research done by Audun Brunes et al show reminders. It handles day to day activities but makes no that high mortality rates are experienced by visually impaired provision for physical activity tracking. Susie finds this due to inactivity. To solve this issue, a smart braille fitness solution clunky and not having the desired physical activity watch is proposed. functionalities. Also, the watch is designed for both visually impaired and the deaf but has no audio functionality which CASE STUDY Susie finds frustrating following her dependence on sound In this section, a case study is carried out on a participant that for communication. experiences the barriers to physical activity caused by visual 3. Personal Trainer: Susie being a student finds having a impairment. An interview was carried out to uncover the case personal trainer very expensive given the available resources and identify key issues, which then would be used to design a she has. During the interview, she said, "Having a personal prototype to remedy the problem. trainer or joining clubs is all to expensive". Therefore, this solution doesn’t fit well with her status. Overview 4. Gym: Susie would love to go to the gym but she says "all Participant good gyms are too far away". Navigating to these places A case study of a visually impaired female University student would be difficult for her considering her . was conducted. Susie a 20-year-old undergraduate student studying at the University of Bath has been visually impaired Based on the information gathered from the interview with from a very young age but makes use of other senses (such Susie the following factors posed a barrier to her engagement

2 in physical activity: cost, transportation and information different health readings. This data is also stored and tagged to retrieval. In terms of cost, Susie says " It is all too the user’s profile for tracking goal progress and performance expensive getting a personal trainer and joining a club". For comparisons. This solution will allow for a simple out of the transportation, Susie points out that "all the good gyms are box setup, information otherwise inaccessible at hand, insights, far off and transportation there will be difficult". "I can’t and recommendations in a small, unobtrusive wearable. The read the time or statistics on a Fitbit without going to my following subsections will describe the proposed design of the phone," says Susie about her information retrieval challenge. watch. The identified barriers prove that Susie needs an alternative solution to her physical inactivity. The objective of this Collecting Context interview was achieved as the various pain points experienced Context is any information that can be used to by Susie were identified. characterize the situation of an entity. An entity is a person, place, or object that is considered relevant to the CONTEXT-AWARE BRAILLE FITNESS WATCH interaction between a user and an application, including Based on the key issues identified, the solution needed to the user and applications themselves. [6] offer a simple set up, monitoring and reporting of health metrics at hand, health insights, and most importantly, visually Using Dey et al.’s widely cited definition, the context needed impaired friendly output of information. The current solutions would be body statistics, age, health metrics such as heart rate, were not fitting for the participant therefore a new solution fitness data such as steps taken and calories burned. This will was to be designed. The solution for this seemed best fit be done using both voice input from the user and from using a for a context-aware mobile or wearable technology similar sensor. to other fitness trackers. A fitness tracker would allow the Voice Input user to set goals and track progress to encourage healthy well There are two parts to collecting context from the user. The being through physical activity. A major difference, however, first will apply to collect the user’s name, date of birth, height, involves re-imagining such a tracker to be operable by the weight and weekly activity. The watch will feature a voice visually impaired. Such requirements lead to exploring the assistant that will guide the user through the initial set up solution using a context-aware braille fitness watch. process. Using a microphone, the watch is able to pick up the Dey et al. mentions three behaviours of context-aware voice inputs and using a speaker, respond. The use of a voice systems: assistant ensures a few things: speech output, voice input, a simple set up, and conversational context. A speech output and • Presentation of information and services to a user voice input tackle accessibility issues with visual impairment • Automatic execution of a service while the simple guided setups and conversational interface offer a more fulfilling and natural experience. Ideally, an agent • Tagging of context to information for later retrieval [6] with natural language processing is preferred as it will allow users to ask for the same thing in many different ways and Although the automatic execution of a service and tagging allow the functionality to feel more flexible. context for later retrieval may prove to be a complex task, the approach is well documented and straight forward. Based Sensor Readings on the health data collected, a logic-based decision can be The second part of collecting context involves using various made and executed automatically. All of this information sensors to capture information. This is the information that can be tagged and stored for later referencing, which in will ultimately be shown live at the braille watch face. The this case can help users know how are improving over time. information captured here will require a time sensor, heart rate On the other hand, presenting information or services to a monitor and pedometer to capture time, heart rate and steps visually impaired user is an unconventional problem requiring taken respectively. Another reading that the user expressed a different approach. the desire for is the number of calories burned. This can be This solution utilizes voice for complex inputs and outputs - achieved with a calorimeter however this tends to be expensive that being information containing more than four characters and impractical. Calories burned, however, can be estimated - as well as a refreshable braille display that outputs simple based on an individual’s estimated basal metabolic rate and quick to read information such as time. The way this solution readings from an accelerometer. would work is a first time user is guided by speech playback through a profile set up using their voice enter basic info Accessible Presentation of Information such as their name, date of birth, gender, height, and weight Designing a user interface for the visually impaired will into the watch. Based on this information, a profile will be differ from traditional interface design guidelines. Without created with recommended daily goals and read out to the the ability to see or read, information must be inputted and user. When a user achieves the daily goal, for example taking outputted without the use of text. Alonso et al. [1] outlines 10000 steps in a day, the watch will notify the user with a modelling user interfaces for blind people. In this, Alonso et vibration or speech playback. The use of sensors will allow the al. presents a framework for visually impaired interfaces that watch to collect relevant data to be displayed on its refreshable require the output of to include speech and braille. For this braille display provided with the option to be readout. A reason, the watch would present information the following quick button press will be used to cycle the display through ways: speech playback and refreshable braille interface.

3 Speech Playback Today voice and speech technologies grow more abundant. For the visually impaired, this is sometimes the only accessible way to use technology. For Susie, a text reader is her only way to know what is on her phone display. In addition to speech playback used in replying to voice inputs, the watch design would include a button to optionally have the braille interface readout. For example, if the watch face is displaying a heart rate of 70bpm, the watch speaker would read out 70bpm. This simply gives the users more preference as to how information is retrieved. Additionally, speech playback will be used to relay more complex messages that the braille interface may fail to do. For example, if a user would like to review their profile, the watch will read out multiple sentences detailing the profile. Similarly, for any fitness insights gathered from the context, the information will be read out to the user when requested.

Refreshable braille interface There are range of methods for the implementation of a refreshable braille interface, such as through the use of actuators. These act as a method of controlling moveable pins to either raise or lower them through a surface to provide ’peaks’ in the surface. These actuators can either be static, or Figure 1. Braille Watches showing Calories Burned [CAL]: dynamic. [16] 2055[kcal](left) and heart rate[HRT]: 84[bpm] (right) Static actuators are those which utilise electromagnetic, or electrostatic forces which can lead to undesirable complexity. An electromagnetic actuator creates a magnetic field to either in testing the feasibility, desirability, and viability of such a attract, or repel a singular pin. Aside from the added difficulty product. The approach taken was to use crafts to build up of working to control appropriate electromagnetism, this type a cardboard prototype with an interchangeable braille watch of actuator also only operates a singular pin. Thus, there is an face that would allow demonstration of the touch information increased cost, and difficulty in the implementation of systems retrieval and button inputs. Although the watch may lack utilising these actuators. [16] true functionality, the aim will be to construct something wearable that feels similar to a watch and can accompany Dynamic actuators use physical motor mechanisms to move the voice and speech demonstrations. To demonstrate the the pins. The rotary actuator is considered superior to the voice and speech playback output capabilities, a prototype linear actuators as described by Sutariya et al. [16] due to its application was created for the smartphone that would mimic ability for feedback. However, the context within which we a similar experience to the watch. The following subsections aim to implement these actuators has limitations on space and will describe the design process of the voice agent and physical requires durability. As such, the linear actuators seem more design of this wizard of oz prototype. applicable for the design of a smart braille fitness watch. Voice Agent Insights on historical data Using AdobeXD, a voice triggered prototype was created that Historical data will consistently be added to as the wearable would emulate the voice agents role in the initial set up, as will continuously monitor the health data. This information well as providing insights. adds more context to a user’s profile that the system can use to provide more accurate insights. The system should be able To begin with, a voice agent mock-up will guide the user to make inferences on the data previously collected to offer through setting up a profile. Each utterance is hard-coded, further insights and recommendations personalized for the therefore, the demonstration will be scripted and role-played. user. For example, the watch may be able to notify or inform The voice assistant will begin by welcoming the user and the user of routine events such as a daily walk. Additionally, informing the user that they will need to set up a profile by the watch will be able to compare data and inform the user of answering a series of questions. Although in a completed their performance over time. product the user would input voice by holding down a button on the watch itself, the wearer will hold down the buttons on the watch while recording their answer into the phone to PROTOTYPE DESIGN role-play the setup journey. For each piece of information In essence, a context-aware braille fitness watch is a complex inputted, the voice assistant will confirm with the user if the design that yields heavy development costs. Given the information is correct. time-frame and experience of the design team, a prototype that would demonstrate the user journey would be sufficient Once all the information is inputted, a profile will be created

4 To demonstrate this for the prototype, the wearer may feel where the buttons are on the watch and understand their function. Pressing the right button while viewing the value Figure 2. Braille card showing heart rate[HRT](left) and 84[bpm](right) will read it out. The voice agent will also be asked to provide information such as an overview to articulate what kind of information is available.

User Study Figure 3. Braille card showing calories burned[CAL](left) and Methodology 2055[kcal](right) The initial briefing given to the participant asked them to operate using a think-aloud protocol whereby they should and readout. In addition to the manually inputted data, the audibly describe their thoughts and opinions of the system profile will include a body mass index ’derived’ from the user’s prototype. Should long silences persist, the researcher would age, height, weight, and weekly activity. In case this is not prompt the participant with non-directive questions such as understood by everyone, it will mention whether or not the "What are your opinions on the system currently?". They were BMI (Body Mass Index) is healthy for that individual based also encouraged to ask questions unsparingly should they have on NHS guidelines. This will show how the initial contextual any. information is used to produce a meaningful insight. Initially, the participant was guided through the voice After the profile is all set up, the voice agent will ask how agents setup process due to its limited capabilities at this it can help. At the request of the user, the voice agent will stage. On completion, Susie was asked to interact with the provide insights on ’today’s overview’, ’yesterday’s overview’ interchangeable braille watch face using the single buttons and ’performance.’ For the overviews, the voice agent will found on each side of the display. To replicate the intended read out the steps taken, calories burned, average resting heart user journey, the display was replaced by the researcher rate for the day, as well as the deviation from the goal. For the present. performance report, the voice agent will read out how often the user achieves goals, the average deviation from the goal Data Collection and increases from the past month. The participant was fully briefed on the nature of the study and consented for an audio recording to be made under assurance For the voice agent, it made sense to mock up a prototype that this would be stored on a secure University of Bath server would show one of many anticipated functions of the watch. and removed upon completion of this unit. The recording The triggers and playbacks are hard-coded thus only allowing also maintained anonymity by ensuring Susies face was not in demonstration of one specific scenario, however, it required frame. Non-verbal communications and unexpected prototype much less to produce than creating a virtual agent that must interactions were noted by the researcher present (e.g. facial be trained with utterances. Hopefully, the design will hope up expressions, repetition of navigation sequence). to the test and present proof on concept. Results Physical Design During the study, Susie mentioned that the sound could have For the physical design, the aim was to create something been sped up, or be adjustable. As someone who no longer wearable that felt comparable to the anticipated product. relies on vision, Susie had become very familiar with using Originally there was an attempt to create an Arduino speech playbacks. The rate that she will normally set her braille interface to allow the pins to move up and down. speech playbacks is fast enough for an unfamiliar individual Unfortunately, the unavailability of pistons leads to a design to understand. This being said, the default speech playback that used gears. This design ultimately became too large and set for the voice agent was slow to the point of impatience. abstract to pass as a watch face prototype. With the lack of access to certain materials, the prototype became a watch that Susie also commented on the design on the braille display. would allow the user to slide a braille card into the watch face. HRT, which was intended to signify heart rate, was not This braille card will replace the Arduino watch face. Pushing understood. This was true initially when looking at STP for the card on the right side would slide the card to display data. steps and CAL for calories, however, she was able to pick it For example, if the watch shows HRT and is pushed over, up fairly quickly. the watch face will show 84 beats per minute. This action of As expected, the braille was too big. It made the watch feel sliding the card emulates the action of pushing the button as oversized and cramped. It was however very simple which to shown in Figure 2. her was one of the most important aspects. If it were to come The prototype design omitted the sensors and instead displayed to a finished design that felt sleek and minimal, it could be a mock readings in braille on the watch face. A visually watch she would wear daily, or at the very least replace her impaired user would be able to touch this interface and Fitbit. She was very pleased with the use of audio, especially understand what the number represents. In doing so, the user the choice of words not being so monotonous. The set up was will be able to read off a physical user interface accessible to extremely simple and overall the product would do what she the visually impaired. wanted it to do.

5 IMPLICATIONS disability and physical activity—United States, Aside from the justification through literature, the enthusiasm 2009–2012. MMWR. Morbidity and mortality weekly and opinions of the participant used in our case study show report 63, 18 (2014), 407. there is potential interest for a smart braille fitness watch to [6] Anind K. Dey. 2001. Understanding and Using Context. be established. However, many concerning points were raised Personal Ubiquitous Comput. 5, 1 (Jan. 2001), 4–7. DOI: about the design of the system as it currently stands. As such, http://dx.doi.org/10.1007/s007790170019 if a product like this were to go to market, it would need considerable reworking and should consider a larger user base [7] Centers for Disease Control, Prevention, and others. to try ensure a more general, marketable product. However, 2010. State indicator report on physical activity, 2010. difficulty would be found in marketing products for those who Atlanta, GA: US Department of Health and Human are visually impaired due to the varying degrees to which Services 14 (2010). this might affect someones life. Our research shows that it is [8] Justin A Haegele, Ruri Famelia, and Jihyun Lee. 2017a. plausible to create specialised products for an individual with Health-related quality of life, physical activity, and an impairment, but still found difficulties in aligning this to sedentary behavior of adults with visual impairments. the specific needs of the individual. Potentially this could be Disability and rehabilitation 39, 22 (2017), 2269–2276. fixed with more intensive levels of user-centred design such as through participatory design. Ultimately, we believe our work [9] Justin A Haegele, Samuel R Hodge, and Francis M shows justification and potential promise for technology to be Kozub. 2017b. Beliefs about physical activity and help facilitate healthy living. sedentary behaviors of adults with visual impairments. Disability and health journal 10, 4 (2017), 571–579. CONCLUSION [10] Kamelska Anna Malwina and Mazurek Krzysztof. 2015. Physical activity is important for healthy living but remains The Assessment of the Quality of Life in Visually inaccessible to people living with disabilities especially the Impaired People with Different Level of Physical visually impaired. To increase access to physical activity of Activity. Physical Culture and Sport: Studies and people living with visual impairment to promote healthy living, Research 67, 1 (2015), 31–41. a prototype of a smart braille fitness watch was designed. The smart watch keeps track of steps taken per day, calories [11] NHS. 2019. Physical activity guidelines for adults aged burnt,heart rates and time. This prototype was tested on a 19 to 64. (December 2019). 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