How the Smart Walking Stick works
The Smart Walking Stick is an assistive device designed to help people living with Parkinson's disease manage Freezing of Gait: a debilitating symptom where the brain sends signals to walk but the feet suddenly fail to respond. It answers with multimodal cueing, delivering three types of sensory signal at once to help the brain re-establish a walking rhythm.
One cueing cycle, step by step
Freezing episodes respond to external rhythm. This animation walks through what happens when the stick's cues are used during a freeze.
Looping animated diagram. A person walks steadily. A freezing episode stops their feet. The walking stick responds with a rhythmic beat, a vibration in the handle and a laser line projected on the floor. The person steps over the line and their walking rhythm returns.
- Walking steadilyThe user walks at their own natural rhythm.
- A freeze beginsMid-stride, the feet stop responding. This is Freezing of Gait.
- The stick cuesA steady beat, a gentle vibration in the handle and a laser line on the floor give the brain a rhythm to follow and a target to step over.
- Rhythm returnsCueing helps movement restart, and the stride settles back into a steady rhythm.
A simplified illustration of one cueing cycle.
Heard, felt and seen
Each cue works on its own. For many Parkinson's patients, delivering them together is more effective than any single cue alone.
Rhythmic Auditory Stimulation
A clear, steady beat plays through a built-in speaker, like a metronome. Research has consistently shown that an external auditory rhythm helps the brain lock onto a regular cadence, improving stride length, walking speed and gait regularity in Parkinson's patients.
Adjustable 60 to 140 BPM
Haptic Vibration Feedback
The handle vibrates gently in the user's hand in time with the audio beat. This physical, tactile cue works even in noisy environments, or for users with hearing difficulties. Audio and haptic cueing together are more effective than either alone.
Felt through the handle
Visual Laser Cueing
A laser module projects a visible line onto the floor ahead. Stepping over a clear line is a well-established technique for initiating movement during a freeze: it gives the brain a visual target to aim for.
Planned improvement
Future iterations will use a green laser for better visibility, following feedback from Parkinson's patients who found it clearer under typical indoor lighting.
Control from a phone, wirelessly
All three cueing modalities are controlled through a companion Android application, developed using React Native and Expo. The app connects to the stick over Bluetooth Low Energy.
Individual toggles
Switch each cueing mode on or off independently: beat, vibration and laser.
Live BPM slider
Adjust the beat speed in real time to match the user's natural walking pace.
Voice control
Hands-free activation with spoken commands such as "turn on laser" or "speed up".
Live gait graph
Real-time visualisation of accelerometer data from the motion sensor built into the stick.
Session recording
Walking sessions are saved and exportable to share with a physiotherapist or carer.
Daily diary
Users can log how their walking felt each day, building a personal record alongside the objective sensor data.
What's inside the stick
At the core is a Raspberry Pi Zero 2W, programmed in Python and housed in a custom 3D-printed enclosure mounted to the walking stick.
Raspberry Pi Zero 2W
The brain of the device: it runs the cueing logic in Python, streams sensor data, and talks to the app over Bluetooth Low Energy. Housed in a custom 3D-printed enclosure on the stick.
MPU6050 IMU
A six-axis inertial measurement unit capturing real-time accelerometer and gyroscope data.
Amplifier and speaker
A MAX98357A I2S amplifier driving a 3W speaker for the audio cueing beat.
Coin vibration motor
Delivers the haptic pulses felt through the handle, synchronised with the beat.
Laser module
Projects the visual cueing line onto the floor ahead of the user.
UPS HAT power
Stable, battery-backed 5V power so the stick works completely untethered.
Custom PCB
A compact printed circuit board designed in EasyEDA to replace the breadboard prototype, consolidating every connection onto a single board that sits directly on the Pi's GPIO header.
Prototype 2 In development
The second prototype moves away from the Raspberry Pi to an ESP32 microcontroller, reducing size, cost and power consumption. It also introduces physical buttons directly on the stick, allowing users to toggle cueing without needing their phone, making the device more accessible and independent for everyday use.
Follow the project, or say hello
If you are a clinician, researcher, funder or part of a Parkinson's organisation, or you simply want to follow along, I would genuinely love to hear from you. There is no mailing list and no form: just send me an email.