Before starting the ideation and design process, we needed to gain a deeper understanding of our case owner to establish and develop the design challenge we wanted to tackle. In order to do this, we first conducted several interviews with our case owner to understand his conditions. Next, we conducted literature research on topics relevant to his condition, wishes, and co-design methods in general. This research is compiled in this context mapping study.
Our case owner is a Dutch male who has been blind since birth. Additionally, he has no hearing in his left ear, also since birth. He is a very active individual that despite his impairments engages in many sports such as cycling and swimming, as well as other activities such as woodworking and gardening. He also writes for the local newspaper and has hosted radio shows in the past. He places great value on his independence, his mobility, and his social contacts. During the first few interviews that we conducted, he indicated that one of his main frustrations was that he sometimes walked into obstacles suspended in the air because he cannot detect these with his guide cane.
After the first interview, an storyboard was made with the main frustrations of the case owner. As said above, after more interviews, the case owner indicated that the main thing he would like a solution too is the obstacle detection in the air (low right corner area of the storyboard). This is our focus point from now on.
Context Mapping Study
In the context mapping study we will discuss the design of a piece of assistive technology and defines a design challenge for visually and auditory-impaired persons. Co-design is known to be a useful design process to employ when designing for a specific user, as it allows designers to gain valuable knowledge, perspectives, experiences, and creative input from the co-design participant. Theoretical introductions to disability in general, and specifically visual and auditory impairments, are made, from a medical/biological perspective as well as a societal perspective. Furthermore, market research was conducted on existing assistive technologies for the visually impaired, and various user-centered design and co-design techniques are explored and discussed. Additionally, the implications and considerations for a successful co-design experience brought forward by this research are discussed.
We conducted two initial interviews with the co-design participant to understand their needs and wishes. The preliminary definition of our primary design challenge is to design a (partially) physical piece of assistive technology that will allow visually and audibly impaired persons to detect obstacles outside of the vertical reach of guide canes. This paper provides insight into the early stages of the design process of assistive technology for visually and audibly impaired persons and offers guidance on how to successfully implement a co-design process. We conclude by noting that further research must be done in order to gain a better understanding of the impairments of the co-design participant, create meaningful design solutions, and ensure an enjoyable experience for all involved (ChatGPT, personal communication, February 23, 2023).
The aim of the Project Designing for Specific Users is to successfully co-design a piece of assistive technology for disabled persons. Our project specifically focuses on visually and auditory impaired persons. This piece of assistive technology should improve and/or enhance an activity or experience in their (daily) lives.
In this paper, we are interested in how to co-design with a disabled person. For this, we looked first into how disability is viewed in society, now and in the past. An analysis was done on how to make successful assistive technologies, and guidelines for how to set up a design process were researched. Examples for our case, a visually impaired and partially deaf person, are given. Think about a walking cane as a successful assistive technology. In order to let the design process go smoothly, human-centered design and different theories on how to do this are discussed. Research is done into both visual impairments and auditory impairments, and the different possible levels of these conditions. This research was used to dive into options for our project. Additionally, market research into existing products was conducted. Lastly, we looked into different approaches for co-design. All of this leads to our chosen design challenges.
2. Literature Study
2.1. Societal challenges concerning visual impairment in the Netherlands
The biggest societal challenges when it comes to care and support of people with disabilities include attitudinal barriers, lack of access to resources such as healthcare, housing, and employment opportunities, inadequate funding for assistive technologies and services, exclusion from decision-making processes at all levels of government, etc. (World Report on Disability, n.d.)
The changing perspectives on disability have been largely shaped by the social model of disability, which views disabilities as the result of barriers created by society. This has had a significant impact on how disabled people are treated and perceived in today’s society. Increasingly, there is greater recognition that disabled people should be viewed as individuals with unique needs and aspirations, rather than ‘deficits’ or ‘problems’ to be solved. This together with assistive technologies has a significant impact on the lives of blind and deaf people. For example, with regard to communication, assistive technologies such as screen-reading software can provide access to printed material and websites for those who are blind or visually impaired; while captioning software can help deaf or hard-of-hearing individuals understand video content. (World Report on Disability, n.d.)
Moreover, the promotion of participation and empowerment of disabled persons has enabled them greater autonomy in their daily lives by allowing them to be more involved in decision-making processes that affect their own lives. This includes providing more opportunities for employment and education, improving accessibility so they can participate fully in society regardless of disabilities, and creating an environment where diversity is respected. (World Report on Disability, n.d.) In order to address the challenges more effectively it is important to promote participation and empowerment among persons with disabilities. Participation refers to actively involving individuals in decisions that affect their lives; while empowerment encourages them to make informed choices about their own lives based on their abilities and capacities rather than relying solely on external support or advice from professionals. Assistive technologies can play an important role in this respect by enabling disabled persons greater independence in terms of communication, mobility, etc., but they cannot replace the need for full inclusion into mainstream activities such as education or meaningful employment opportunities if individual autonomy is truly desired. (World Report on Disability, n.d.)
2.2. Assistive technology
An assistive technology (further referred to as AT) is anything that helps disabled people with tasks non-disabled people can do. This can range from software to a physical solution to a combination of both. The goal of assistive technologies is, by helping with physical elements, and social inclusiveness (Hersh & Johnson, 2008b). Depending on the kind of AT, there is a serious problem with abandonment. A few reasons for abandonment can be: the device does not fit the user, not accomplishing the task the user wishes to do, and is not comfortable for long-term use. The biggest cause of abandonment is changes in the needs of the user. (Petrie et al., 2018). In order to successfully adopt assistive technology in an impaired person’s life, a framework was researched and set up. In this framework (Kintsch & DePaula, n.d.), it is key to have a collaboration between the participants involved in the adoption:
- The actual users (in our case, the case owner)
- The caregivers/the people who are involved in the user’s life
- The designers
- The assistive technology specialists, assistant of user during adoption process
ATs are often abandoned because the goal set up by the user is not fully fulfilled and requires too much effort from the user. An AT is successfully adopted into the user’s life when the user can use the AT easily in a variety of environments, the user likes the AT and gets value from the AT, and when the AT helps empower the user. (Kintsch & DePaula, n.d.).
In the table (Table 1) above, there is an overview made of the previously mentioned 4 groups that need to collaborate in order for the adoption process to be successful. In this table, there are the goals, needs, expectations, and efforts described for this framework to be successful. The framework consists of multiple phases: Development (determine goal), selection (collaborate with users to create final solution), learning (learn users how to use the AT), and integration (users adopt the AT in their daily life). In the last phase, designers gather feedback which could result in the phases starting over again in a vicious circle. (Kintsch & DePaula, n.d.)
Appropriation of technology is about users using the AT for a task that the designers never envisioned. It can happen when there is currently no tool for the specific task the users want to do, or it can happen because the task is easier with this AT (it takes less time). To help designers navigate this, guidelines were set up: allow for interpretation, provide visibility of functionality, expose intentions, focus on support rather than control, configuration, and learn from appropriation. (Dix, 2007)
For our case example, a visually impaired and partly deaf impaired person, assistive technology is focused on the senses of touch, hearing, and smell. The help with obstacle avoidance is the one where the most research for AT is done, for example, a walking cane as a solution. These canes can have additional functions, like being equipped with lasers and sensors or a GPS system (WeWalk, 2019). There are also devices developed that can help them read text. For example, audiobooks or software (KNVB reader, 2014) that reads to them what is on their screen. More advanced solutions are scanners that read aloud to the user what is in their mail (the paper version). (Hersh & Johnson, 2008)
To conclude, to design a successful AT: the designers need to develop the AT with a clear overview of what the user wants to achieve with the AT, easy to use, highly customizable, durable, and according to the aesthetic preferences of the user.
2.3. Human-centered design
Human-centred design is a design methodology and philosophy in which the needs, goals, and success of the end user are taken into account throughout the design process (Lanter & Essinger, 2017). Applying a human-centred design approach is an important way to improve accessibility, usability, acceptability, and appropriation, especially when it comes to designing assistive and rehabilitation technologies for disabled users (Guffroy et al., 2017). Traditionally, Norman’s model (Norman, 1986)(Norman, 2013) is used for interactive system design to help designers understand how the user interacts with the system. According to Norman’s model, during the process of performing and evaluating an action, the user goes through seven stages: establishing the goal, forming the intention, specifying the action sequence, executing the action, perceiving the system state, interpreting the state, and evaluating the system state with respect to the goals and intentions (Norman, 1986). However, it should be noted that in practice, an action is often not a simple sequence of stages. Stages may appear out of order, be skipped, or be repeated.
The user has certain goals with regard to using the system, which are expressed in psychological terms, whereas the system presents its current state in physical terms (Norman, 1986). The difference between these goals and the system requires Gulfs to be bridged: the Gulf of Execution (from user to system) and the Gulf of Evaluation (from system to user). Designers can bridge the Gulfs by either moving the user closer to the system, or by moving the system closer to the user (Norman, 1986). To move the system closer to the user, designers should provide a system interface design that matches the user’s mental models of the system.
However, Norman’s model only focuses on the end user of the product or system. This presents one of the most important implications for our own design vision in this project. For the design of assistive technology for disabled people, other relevant stakeholders such as caregivers, family members, teachers, specialized educators, etc. should be identified and collaborated with during the design process as well (Marti & Bannon, 2009) (Markopoulos et al., 2011). This is because disabled users may have difficulties expressing their needs. Additionally, since these other stakeholders should also be considered as direct or indirect users of the technology, their needs should be taken into account as well (Markopoulos et al., 2011).
We as designers must beware that placing the focus on individual people when applying user-centered design methods might improve the design for that specific person but might make it worse for the rest of the user group. “The more something is tailored to the particular likes, dislikes, skills, and needs of a particular target person or group, the less likely it will be appropriate for others” (Norman, 2005). The implementation of empathy-building presents another important implication for design ethics during this project. This is often the starting point of human-centered design processes in which designers seek to understand their intended users in order to inform technology development (Bennett & Rosner, 2019). Recent design guides frame empathy-building as even more important when users have disabilities (University of Cambridge, 2018). However, since scholars agree that design cannot be premised on empathy alone, several techniques such as simulations guided by disabled people (Burgstahler & Doe, 2004; Gaudion et al., 2014) and codesign exercises in which designers enlist disabled people as partners (van Dijk et al., 2016).
2.4. Theoretical introduction to visual and auditory impairment
2.4.1. Visual impairment/total blindness
Several gradations in visual impairment are defined. It is commonly accepted that there are four different levels: normal vision, moderate visual impairment, severe visual impairment, and blindness.
The most significant proportion of the visually impaired fall in the category of ‘low vision’, which is levels two and three of the above list (WHO | Visual Impairment and Blindness, 2015). Here we will focus on the fourth and most extreme level categorized as ‘blindness’ or often called ‘complete’ or ‘total blindness’, which means that a person has lost all forms of vision whatsoever. It is estimated that 253 million people worldwide have some form of visual impairment, and 36 million of them have blindness. Most blind individuals develop blindness from the age of 50 years or older. Some estimations show that about 1.4 million children globally are irreversibly blind (Ackland et al., 2017). Complete blindness often means that the eye is not able to detect light or that the connection between the brain and the eye is not functioning properly. This can have several causes. A common cause of complete blindness is glaucoma. This condition damages the optic nerve connecting the eye to the brain. This cause is most prevalent in older people and takes a while to develop and cause blindness. A lot of types of conditions can cause blindness from birth. The most common causes are congenital ocular anomalies, i.e. defects in the eye present from birth. These defects in the eye cause the eyeball to be deformed or totally absent and thus dysfunctional from birth (Dash et al., 2022) (Gogate et al., 2011).
Individuals suffering from these congenital ocular anomalies are born blind and therefore need some assistance throughout the rest of their lives. However, most blind individuals tend to become more independent later in their life, due to vision rehabilitation training. It must be noted that blind individuals lead a normal life, but have their own way of doing things. It is a misconception that blind people are very limited in their ability to lead their life, however, they of course do encounter several challenges due to inaccessible infrastructure and social challenges (Kumar, 2018). Vision rehabilitation helps overcome these challenges and is defined as restoring functional ability and improving quality of life and independence in an individual who has lost visual function through illness or injury (Institute of Medicine (US) Committee on Assessing Rehabilitation Science and Engineering, 1997) (Crowle, 2010). A neurological method can be effective to regain sight for ‘low vision’ individuals. This is however ineffective for completely blind individuals. Then a physical approach is used. This is often a combination of mobility training, home skills training, and occupational therapy (McGrath & Laliberte Rudman, 2013) (Berger et al., 2013). These types of vision rehabilitation training have a big impact on the life of blind individuals and make them often pretty independent. This independence is often obtained through assistive technologies. For mobility, the most common aids are service dogs and canes. The most common electronic assistive devices are screen readers, speech recognition, and braille displays (Social Sciences, n.d.).
2.4.2. Auditory impairment/prelingual partial deafness
Auditory impairments come in different forms. An individual can be completely deaf or have partial hearing loss, and this can differ from left ear to right ear. Also, a subdivision is made between prelingual and postlingual deafness. This means becoming deaf before or after developing speech or language. Here the focus will lie on prelingual partial deafness. The main characteristics of partial deafness include difficulty with oral expression, difficulties with social or emotional skills, difficulties hearing consonants and avoidance of social settings (Watson, n.d.). These characteristics make conversation harder and can often lead to a feeling of isolation, which may lead to depression (Hearing Loss and Older Adults, 2018). Prelingual partial deafness is estimated to occur in about 0,07% of people in the Netherlands (de Graaf et al., 1998). It often has congenital causes, of which there are many. Several types of treatment are possible, hearing aids and cochlear implants are possible, but both will not restore the hearing to that of a normal functioning ear. Cochlear implants work internally and stimulate the auditory nerve connecting the inner ear to the brain (NCD – Cochlear Implantation (50.3), n.d.).
2.5. Market research on existing products
WeWalk is one of the most promising products on the market. It can be attached to already existing walking canes to provide warnings to low-hanging obstacles in the form of vibrations as well as navigation. It is available on the market for €695.00.(WeWalk Taststok Met Navigatie, n.d.). Although the features the “WeWalk” provide are in the same direction as we wish to aim, the price and extra weight it adds are two major drawbacks. there is much to learn from the “We Walk” product such as the ability to attach to pre-existing walking canes.
The Sense Five is a walking cane being developed by WertelOberfell. It uses ultrasonic sensors in order to detect low-hanging obstacles and provide haptic feedback to the user by changing the texture of the gripping area. This is possible by rotating the handle with an electric motor which causes the specially designed grip to change the texture. The only 2 major concerns would be the difference in grip and if the haptic feedback still works under firm grips (Sense Five Design Concept – WertelOberfell GbR, n.d.).
VTT Technical Research Centre of Finland was developing a wearable device that uses radar in order to help visually impaired people with orientation. Due to the use of radar, it is possible to use the device under a coat. The wearable approach is different and opens up the ability to look for solutions that don’t involve the walking cane. It is also important to keep in mind that although they did not release this product for sale after that, radar technology tends not to be cheap and the extra weight could limit mobility rather than increase it (Finland, n.d.).
The reason for doing this research is to see the already possible technologies and their imperfections. More importantly, why is the case-owner not using these products? This can have to do with the products being unknown, being too pricey, or not available in the Netherlands. One of the main concerns by the case-owner is the weight of the product. He has experienced a cane with gps before, but thought it was too heavy to use comfortably as a long-term solution. Therefore most existing walking canes with obstacle detection are out of the case-owners comfort zone since the sensors, hardware, and batteries add to the weight of the cane. Another concern is the price of some products, especially in combination with the above concern, the case-owner has mentioned products not being worth their high price if they are not comfortable for daily use.
Co-design (or participatory design) is a subset of human-centred design where the design is done with the users, rather than for the users. Users are seen as active and creative participants in the design process by contributing valuable knowledge, perspectives, and creative designs or design input (Magnusson et al., 2018). A co-design mindset will influence the way in which designers see their users as well as the design process as a whole (e.g. with regard to the activities during the design process). Co-design is a very useful design process to employ when designing for specific users (e.g. users with disabilities) because co-design activities provide an improved understanding of the design challenge at hand (Magnusson et al., 2018).
Generally, the literature recommends choosing a highly individual approach toward adjusting codesign techniques for different participants (Hendriks et al., 2015). Generally, there are some common challenges and pitfalls to consider when preparing co-design sessions and choosing co-design activities and tools (Hendriks et al., 2015): the positioning/framing of the participants’ impairment, the aim for equivalence, balancing of different viewpoints, dealing with ethical challenges, and the adjustment of codesign techniques to the participant(s).
Many standard design tools such as post-it notes, drawings, and lo-fi paper prototypes are visual tools, and are thus not suitable for co-designing with people with visual impairments. Co-design activities can be adapted by e.g. using tactile prototyping materials instead of pen and paper or using NFC or RFID tags to sonify objects (Magnusson et al., 2018). There are several examples of co-design projects with visually impaired individuals, as well as different interesting co-design techniques and methods.
The first example comes from the HaptiMap EU project (Magnusson, Rassmus-Gröhn, et al., 2009). This study was conducted to gather user requirements for navigation and map software (Magnusson et al., 2018). The study consisted of three parts. First, a focus group test, on both a conceptual thinking and field test level) was conducted. Next, a diary study was conducted, which was aimed at priming the participants to actively think about the design challenge. Finally, a design workshop was held where the participants brainstormed solutions by building low-fi prototypes. Something to consider during our own project is the framing of the activity, since it may be considered “childish” or a “kindergarten” kind of activity (Magnusson et al., 2018).
The second example comes from the Mobile Oracle project (Magnusson, Pielot, et al., 2009). In this project, Wizard of Oz prototyping was used, where the functionality of a technology/functionality that is not yet developed is ‘faked’ by a human. With regard to our project, this technique allows designers to easily test auditory interface prototypes and can thus be useful when developing assistive technology for people with visual impairments (Magnusson et al., 2018).
The third example comes from a co-design workshop study (Brewer, 2018). In this study, two different types of co-design exercises were tested: voice-based and tactile-based co-design exercises. Both had their advantages and disadvantages. Voice-based co-design often created a situation where not all participants’ opinions were reflected in the final presented idea (Brewer, 2018). A major challenge of tactile-based co-design is the difficulty of iterating on a visually impaired participant’s visual design idea. However, this can be mitigated by requiring participants to describe their solutions aloud during the building phase and to pass their prototypes around to others (Brewer, 2018).
A final example is a design tool that encourages creativity: Magical Bits (Grufberg & Holmquist, 2011). Magical Bits are simple physical models representing the main function of a future end product. The Magical Bits method was applied in a workshop with employees of the Mobile Life Centre. The participants were informed that the lo-fi prototype glasses they had were a pair of magical glasses with which they could see whatever they wished for in varying contexts and scenarios. This yielded many creative ideas.
3. Discussion and conclusions
Our aim for the Project Designing for Specific Users is to successfully co-design a piece of assistive technology for visually and auditory impaired persons. This piece of technology should improve and/or enhance an activity or experience in their (daily) lives. We seek to establish a partnership with the co-design participant, by placing them on the same level as us, the designers. We wish to gain valuable knowledge, perspectives, experiences, and creative input from the co-design participant.
In order to achieve the best co-design experience for all participants, there are some implications and considerations. Most importantly, we should respect the personhood and individuality of the co-design participant. Furthermore, we should consider the implications brought forward (especially) that visually impaired individuals have their own way of doing things and leading a normal life(section 2.4) and consider the common challenges and pitfalls when preparing for a co-design session and choosing co-design activities and tools such as the positioning/framing of the participants (section 2.6). We should carefully consider the co-design participant’s impairments (fully blind and partially deaf) and should choose and/or adjust appropriate co-design methods accordingly.
Based on the literature research, the initial interviews that were conducted with the co-design participant, and feedback we received during the context mapping presentation, we defined a preliminary design challenge consisting of two parts (Design Challenge 1.0). Our co-design participant indicated that he would like to have a bit more social interaction and have a product that could detect obstacles suspended in the air (which he could not detect with his guide cane).
Primary design challenge: design a (partially) physical piece of assistive technology that will allow severely visually impaired to blind people to increase their amount of social interaction.
Secondary design challenge: design a (partially) physical piece of assistive technology that will allow visually impaired persons to detect obstacles outside of the vertical reach of guide canes.
Based on the co-design session and the wishes of our case owner, we defined our final Design Challenge 2.0.
Design a (partially) physical piece of assistive technology that will allow visually and auditory impaired persons to detect obstacles outside of the vertical reach of guide canes.
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