ES1050 2023-2024 Cardio machine use for visually impaired

Visually impaired individuals may face many challenges in daily life which go unnoticed by the general population. 1 of those challenges is using cardio equipment, whether at home or in a public gym. In ES1050 our team was tasked with tackling this problem with access to the firsthand insight and experience of a visually impaired gym goer through client meetings on zoom where we were able to ask question and receive feedback on design concepts.

When talking with our client there was an emphasis on the concept of universal design and being able to use a cardio machine without bringing extra equipment themselves. With these concepts in mind our solution become a new cardio machine interface that would utilize tactile buttons and audio feedback to increase the accessibility of the device.

Our prototype is a proof of concept based off a basic treadmill and uses buttons within a frame that goes over top of a laptop (Which represents the treadmill here). The laptop is locally running Java code that the team wrote which implements a text-to-speech library to play audio and give information to the user corresponding to what key is pressed. For example pressing the key corresponding to speed increase would play audio to notify that the speed increase button has been pressed and would read out the current speed of the machine. This is modeled after cell-phones, laptops, TV's and even bank ATMS which all have text-to-speech / read aloud features (which appropedia also has).

The Buttons were 3D printed and the frame was made from basic plywood with guiding rails. The layout and dimensions were determined from the laptop size and key layout. The next section will go over the mechanical design and rationale in depth as that is the part of the project I was responsible for.

Each button was designed in Onshape, 3D printed with PETG and consisted of 3 components, the shaft, chamber and modular face. The shaft has a wide top to put the button face on and a long shaft underneath. This makes contact with the keyboard and transferred the force to actuate the keys. The chamber goes into the plywood frame with a friction fit and has a hole that the shaft will go through so that it slides with low friction. Finally the modular button faces goes on top of the shafts to identify and differentiate each one of them.

Each button face has raised lettering that is able to be read visually as well as by touch, along with that there is a corresponding raised symbol for quick identification of buttons. With this design someone with worse impairment would be able to deduce the button from the raised lettering on first usage and then identify the button by symbol the following times. Raised lettering was chosen because it is more universal and there are many visually impaired individuals who don't know braille for various reasons, e.g. losing sight later in life. Bright contrasting colors were chosen for the buttons, raised letters + symbols and frame for easier identification for those with partial sight.

The next ideations of this project would be to combine the text-to-speech and button frame into 1 integrated system using a microcontroller, Audio files, speakers, electronic switches etc. By iterating the project in this way, it would allow for custom "overlays" to be made for different cardio machines. An electrical membrane could be implemented between the button shaft and chamber to trigger the audio while still allowing for the machines built in buttons to be pressed with the shaft so that taking apart machines wouldn't be necessary. In addition more testing on print quality of different text fonts, letter spacing and size could help with optimizing readability and ease of use for the raised lettering. Raised lettering labels could also be added to the frame above buttons to denote them without the worry of size constraints on the button face. The final logical conclusion to this project would be to work with the companies integrates these features into the machines at the manufacturing level.

There's also room for extra features to be added to the text-to-speech implementation such as passive audio output of current stats such as time passed, heartrate and calories burned which loop on a set time interval. Other additional features would be a toggle to turn audio output off, as well as a headphone jack to transmit audio output through personal earbuds and headphones.

Alternatively, the button faces could be modified and customized to different cardio machine buttons and directly attached to them with adhesive and 3D printed pieces could be made for an entire interface overlay. This would allow for an easy open source D.I.Y solution that could be implemented in personal homes or at commercial gyms (at the owners discretion) with the tradeoff of losing audio feedback. Despite this I believe this could still be a viable option as a lower level but more easily procured solution through distribution of 3D printing files.