Joseph Kim





Wave is a post-stroke motor rehabilitation platform designed for physiotherapists and patients. A companion IoT motion sensor provides a point of physical-digital interaction, enabling Wave to read the patient’s arm movements during rehabilitative sessions. The platform and sensor were built by me as an independent project at Bitmaker.


For stroke victims, motor rehabilitation is a vital part of brain recovery that involves professional treatments from physiotherapists. However, access to physiotherapists are limited for some people so treatment may not always be available.

How can we make this type of healthcare more distributed so that patients have greater access to treatment and physiotherapists?


While some therapies require specialized equipments, everyday motions such as grabbing objects are effective treatments as well.

A web-based healthcare platform was created to connect patients with physiotherapists who can administer simple motor rehabilitation treatments and monitor the patient’s response time and accuracy.

Wiimote + Internet of Things = Distributed Motor Rehabilitation?

During my research, I came across an old project on Youtube that reengineered a Wiimote to enable finger tracking using a computer program. While the user’s physical interactions aligned with some common post-stroke motor rehabilitation treatments, the technology was tethered to a single computer using Bluetooth. Was there a way to distribute this experience across multiple users on a dedicated platform?

Johnny Lee’s Implementation of Finger Tracking using a Wiimote (2007)

Johnny Lee’s Implementation of Finger Tracking using a Wiimote (2007)

An IoT Motion Sensor with a Wiimote IR Sensor (2015)

An IoT Motion Sensor with a Wiimote IR Sensor (2015)

The solution was to replace Bluetooth connection with IoT technology so that the hardware is not tethered to a single computer but a web platform. For Wave, this meant that rehabilitative sessions can be administered to users wherever a stable Internet connection was available.

“Point at the Target” Rehabilitative Session in Wave

“Point at the Target” Rehabilitative Session in Wave

Receiving Remote Treatment from Physiotherapists

In addition to self-administered treatment, physiotherapists are able to initiate remote treatment. A notification system was implemented to begin a shared view of a rehabilitative session. While a self-administered treatment randomly generates the patient’s targets on screen, a shared treatment allows the physiotherapist to create targets by clicking anywhere on the canvas.

A Physiotherapist Initiating a Shared Rehabilitative Session

A Physiotherapist Initiating a Shared Rehabilitative Session

Tracking Progress with Interactive Data Visualizations

Since Wave tracks both the patient’s average completion time and accuracy per session, a time series chart was chosen to visualize the data. To allow the patient to compare his performance at a given time, I decided to make the chart interactive so that patients can toggle between completion time and accuracy.

Toggling Between Completion Time and Accuracy

Toggling Between Completion Time and Accuracy

A Need for User Empathy

When this project was first developed in 2015, I didn’t provide enough design considerations for accessibility. Having focused too much on the technology, I failed to properly empathize with the users and their physical abilities. This resulted in a user experience that was unsuitable for patients with impaired motor control.

Improving the User Experience for Accessibility

The most noticeable problem was that the button to activate a rehabilitative session was too small for users with impaired motor control. Since motor control affects how they aim their mouse pointer on the screen, the button needed to be bigger.

The most important part of changing the user experience is to test the changes against real users. Unfortunately, with limited time, it was difficult to conduct usability tests. However, with this redesign, it opens up new problem spaces to explore through additional user research.

Closing Thoughts

Revisiting Wave made me realize the importance of having user empathy when designing products. Without a clear understanding of the users, you risk investing in a solution that fails to address their needs and violates their trust in your designs.