Giving the right kind of feedback is an important part of any design that interacts with a user, for the visually impaired it is even more important to be clear when we give feedback. To make sure that the right message gets across without sounding impolite or problematic.
Designing any kind of digital application or website, the way we use language is very important. However when we design for the visually impaired it is no longer just the way we want to present our product and the personality of the product to the target audience but there is a whole different aspect to it. When we write text for an accessible project we need to keep in mind that the VIPs most likely will use the text-to-speech function. This means that they have to go through all the text, so being clear and succinctly is a must. Do not lose yourself in long sentences but rather choose to go with clear statements. For example when one writes for a wayfinding application, “Go right in twenty meters” is better than “In twenty meters please turn right at the Weesperzijde.”
Make sure that you make the links you are using in your project are descriptive. Do not just use ‘Click Here‘ but rather opt for ‘Click here to add to cart‘. This way your project is easier to navigate with a screen reader (amherst.edu, 2017).
Recommended is to test your website or application with a screen reader to test how much text it is and how long it takes for you to get through this. After all it is very different when you imagine it rather than testing it out yourself.
Presbyopia is something that comes with age, after the age of 40 the lens in your eye starts hardening. Other things such as color vision and cataracts are also linked to the progressing age (Heiting, 2017), so it is not a surprise that a lot of VIPs are senior citizens. This means that when you design with the VIPs in mind you can look at designing for seniors as well; including the tone of voice. A respectful and polite tone of voice might be the best option. In co-creation sessions with the visually impaired this was also brought up.
In the end the tone of voice of your project has to match the goal and the target audience. In every case it will be different but the above mentioned points are good starting points before you start writing your texts.
Voice-based interfaces are becoming more common than before. Audio assistants like Siri and Cortana have been around for a few years now. These platforms are becoming more available even for accessibility. With the use of templates from Google and Amazon, a design of a voice-driven app is a relatively simple process. If we consider just the voice input, we still see the majority of VIP relying on visual or tactile interfaces. It is possible that the voice interaction needs a few more years of development to be efficiently used. On the other side, VIPs often use Apple devices for their voice-over accessibility feature.
The use of audio as feedback is often criticised for not being usable enough. When we asked VIPs during our co-creation about the prefered way of feedback, they responded that the method doesn't matter, as long as it's precise. Therefore we assume that audio has a potential to be a conventional method of feedback for wayfinding of VIP with the of the soon to be finished Galileo project. The audio has apparent advantages not requiring the use of hands. One point to keep in mind when working with sound is that you do not want to isolate the user from the sound of the environment as it is a precious channel of information. The fact, which the soundscapes of the cities are the essential part of creating a cognitive map might be considered when designing artificial sounds. In a real word, a VIP could use a source of a characteristic sound as a checkpoint. The downside is that the some of these places are not making the sounds constantly. e.g. a Bus stop, Factory, a cafeteria etc. By including sound icons as a part of interface solves the problem of reliability by having the sound available on demand.
One of the requirements that came up from our co-creation session was the need for constant feedback on the directions. Either affirmation or warning from straying from the paths might be done with the use of geofencing or spacialy related sounds. You imagine the planned route as an are of safe space, the outlines of that path as warning zone and the further are as a an impulse for a prompt for rerouting and so on. As the sound has to be tied to location, again, this is an area that will become more available with the improved precision of EGNSS.
Another way to communicate with VIPs is throughout tactile stimulation. Vibrations, shakes and little movement can be used to inform. Playing with diverse duration, rhythms and intensities can be a way to express different ideas or announce different situations.
Anyhow, tactile or haptic communication should not be an alternative way to give feedback to VIP but as a complement. Moreover, the research paper by Ashraf, M. and Ghazali, M. (2017) “Interaction Design for Wheelchair Using Nintendo Wiimote Controller” claims the following:
“Another work proves the efficiency of tactile over audio especially for outdoor use. [...] Therefore, we may conclude that tactile interaction shows better performance than audio for blind users."The document “Vibrotactile feedback to aid blind users of mobile guides” by Ghiani, G., Leporini, B., & Paternò, F. (2009) also reaffirms that implementing vibrotactile feedback especially to communicate in public spaces is helpful. The main reason is that it offers a solution that does not interfere with the listening of the user.
The haptic channel is recommended to give not very complex feedback. The more intuitive and simple it is, the less learning it will require. An example of intuitive haptic feedback is increasing the vibration when the user is approaching an obstacle. It is important to keep in mind that vibrations are not enough to provide the whole information.
Nevertheless, a study carried by Ghiani, G., Leporini, B., & Paternò, F. (2009) at the paper “Vibrotactile feedback to aid blind users of mobile guides” showed that vibrotactile feedback is adequate for devices that are going to be used for a long period or constantly. The reason is that this kind of communication usually requires some period to get familiar with the different type of feedbacks.
Besides, using patterns to provide different information is necessary. The patterns can vary in intensity, rhythm, repetition, duration, have an increase/decrease... Regarding the vibration intensities, a short vibration is considered the one lasting around 700 ms, a long one around 2 s.
Concerning the continuity of the feedback, users may have different preferences. Some VIP find annoying having constant haptic responses. Others, however, feel more confident having a continuous confirmation. This theory is verified not only by the co-creation session we did with 6 VIPs, but also by the study done by Ghiani in which the users complete the task faster when they received constant vibrotactile feedback.
Keith Kirkland, the CEO of the project Wear Works, announced that after a test they found out that around the 80% of the participants preferred having a haptic response that let them know that they are moving in the wrong way. Nevertheless, our co-creation session showed that each individual is really different. Thus, a moldable haptic feedback is preferable.
Due to the diverse preferences of the VIP, the tactile communication channel should be customizable. To do so, it is recommendable to add some settings in which the user can customize the parameters (like intensity, amount and duration) of the haptic feedback.