The Problem
Radio communications are inaccessible to deaf drivers, limiting their ability to receive strategic and safety-critical information.
Existing Solutions
Whiteboards, hand signals, and even in-car FaceTime are limited, distracting, and unsuitable for dynamic racing conditions.
SR Comms
A steering wheel-mounted human-machine interface providing reliable, hands-on-wheel communication through embedded hardware and a native Android platform.
A First-of-Its-Kind Communication Platform for Deaf Motorsports Drivers
SR Comms is a first-of-its-kind communication platform developed to provide real-time race communications for deaf and hard-of-hearing motorsports drivers.
Endurance racing depends on constant communication between the driver and pit crew for strategy, safety, and vehicle diagnostics. Conventional radio systems are inaccessible to drivers who cannot hear. SR Comms was engineered from the ground up as a complete hardware and software ecosystem — a steering wheel-mounted wireless controller, embedded firmware, and a native Android application unified into a single driver communication interface.
The ProblemRadios Don't Work for Deaf Drivers
Traditional motorsports communication relies on radio headsets for pit strategy, fuel windows, mechanical diagnostics, track hazards, driver condition, and emergency response. Silent Racing was the first race team in the United States to field deaf racecar drivers — and for them, that entire communication channel simply doesn't exist.
Before SR Comms, the team relied on whiteboards, hand signals, and live video calls. Each broke down under real racing conditions: too slow, too limited in vocabulary, too dependent on line of sight, or too distracting for a crew member who had to stay glued to a phone.
| Alternative | Limitation |
|---|---|
| Whiteboards | Extremely slow, unreadable at speed |
| Hand signals | Limited vocabulary, line-of-sight only |
| Video call stream | Distracting, bandwidth-dependent |
| Touchscreen-only app | Requires taking hands off the wheel |
| Wired push-to-talk | Cable fatigue, connector failure at the steering column |
| SR Comms | Fast, wireless, scalable — highest development effort |
To the best of my knowledge, no commercially available motorsports communication system provided this complete functionality when the project began — bidirectional messaging, hands-on-wheel operation, fast message generation, high cockpit visibility, endurance-race reliability, and accessibility for deaf drivers, all in one integrated system.
RequirementsFive Constraints, One System
Functional
- Real-time bidirectional messaging
- Rapid message generation
- Reliable across 24+ hour races
Mechanical
- Steering-wheel integration
- Low mass
- Secure mounting under vibration
- Ergonomic button placement
Electrical
- Battery-powered, rechargeable
- Bluetooth connectivity
- Multi-day runtime
Human Factors
- Hands stay on the wheel
- Glove-compatible controls
- Tactile feedback, high visibility
- Learnable under stress
Scalability
- Customizable message trees
- Multilingual operation
- Off-grid communication
- Uses beyond motorsports
System ArchitectureDriver Input to Crew, in Two Hops
Steering-Wheel Controller
- nRF52840-based embedded controller
- Eleven physical inputs
- Rechargeable Li-ion battery
- Custom mechanical housing
- Wireless BLE link
Android Application
- Kotlin, Jetpack Compose
- MVVM architecture
- Editable decision-tree messaging
- Google ML Kit translation
- Meshtastic BLE/protobuf link
Communication Outputs
- Group cellular messaging
- Off-grid LoRa mesh
- Multilingual translated messages
Mechanical & HMI DesignBuilt Around the Driver's Hands, Not the Electronics
Conformal, Not Bolted-On
The controller housing was designed around a 3D scan of the steering wheel itself, giving it a conformal fit rather than a generic clamp-on box. Button placement, wire routing, and strain relief were all built into the mounting geometry from the start.
- Lightweight FDM-printed housing
- Internal wire routing with motorsport-grade concentric twisting for strain relief
- Replaceable buttons and reverse-engineered, custom-printed button caps for colors that weren't available commercially
Designed for Gloves and Stress, Not a Desk
Every control decision was made for a driver wearing racing gloves, working from muscle memory under stress. Buttons are large, color-coded to match the on-screen decision tree exactly, and spaced for rapid recognition without looking away from the track. An early tactile switch revision replaced buttons that lacked physical feedback, after driver testing showed drivers couldn't confirm a press by feel alone.
Hands-on-Wheel, Eyes-on-Track
The finished system keeps both hands on the wheel and both eyes forward. The controller sends button presses over BLE to a dash-mounted phone, which displays incoming crew messages in high-visibility, color-coded text — legible at a glance during competition.
Embedded HardwareWireless by Design, Not by Convenience
The controller is built around an Adafruit ItsyBitsy nRF52840 Express, paired with an Adafruit PowerBoost 1000C charger board and a rechargeable Li-ion battery. Momentary tactile pushbuttons and a power switch round out a fully self-contained, wireless input device mounted directly on the steering wheel.
Why Wireless, Not a Coiled Cable
Most race cars route a wired push-to-talk button to the radio through a coiled steering-column cable — a cable that, over years of racing, is a recurring failure point. Going wireless over BLE eliminates:
- Conductor fatigue from repeated steering cycles
- Connector failures at the steering column
- Cable snagging and steering restriction
Battery sizing was validated with a straightforward calculation — 1200 mAh capacity against an estimated 40 mA average draw — yielding a 30-hour minimum runtime, well past the 24-hour endurance-race requirement. Bench testing has gone further than that minimum: the current controller has run continuously for over 72 hours, and an earlier version of the system remained functional after being left powered for a full seven days.
Software ArchitectureFrom App Inventor to a Native Android Platform
The application follows an MVVM architecture: a Compose UI layer handles display and input, ViewModels manage state and logic, and a manager/repository layer handles BLE communication and data persistence. Contacts, decision trees, and configuration are stored in Jetpack DataStore, with navigation managed through Jetpack Navigation Compose.
The app maintains two simultaneous BLE connections — one to the steering-wheel controller, one to a Meshtastic node — with mesh communication implemented over Protocol Buffers via Square's Wire library. At the core is a decision-tree messaging model: a small number of button presses traverses a structured tree to generate a complete, predefined message. Trees are fully editable, persist across sessions, and support different configurations for racing or industrial workflows.
Interface & CommunicationWhat the Driver and Crew Actually See
Racing
- Decision-tree messaging
- Group SMS/MMS team chat
- Saved contacts & editable buttons
- Save/load custom presets
- High-visibility incoming messages
Translation
- 53-language support
- Runtime, auto-translated interface
- Locally downloaded language models
- Fully offline after install
Meshtastic
- BLE connection to LoRa node
- Off-grid message routing
- Direct node selection
- Cellular / mesh mode toggle
Every on-screen button is color-matched to the physical button on the steering wheel controller, so drivers can navigate the message tree from muscle memory without reading labels mid-corner. The same decision-tree engine also drives the industrial configuration, with job-specific presets and a cellular/mesh toggle for connectivity-limited sites.
ValidationTested Where It Actually Matters — In the Car
Earlier versions of the system were used in motorsport competition over roughly four years, across races ranging from 7 to 24 hours in length, with direct feedback from Silent Racing's drivers and crew. Earlier versions of the system supported the team during multiple podium-finishing endurance events. The revised, native-Android system is scheduled for its next full validation at a race weekend at Circuit of The Americas.
Beyond MotorsportsThe Same Architecture, Different Job Site
Custom decision trees, on-device translation, off-grid mesh communication, and large high-visibility controls weren't built for racing alone — they're general-purpose tools for any high-noise, low-connectivity, or multilingual work environment.
The Android app already ships with job-specific presets for crane, mining, and dump-truck workflows alongside the racing configuration — the same platform, reconfigured for a different set of hands.
Current Production-Development DirectionPrototype to Production Hardware
Current Prototype
- Commercial development boards
- FDM-printed housing
- Handmade wiring harness
- Off-the-shelf tactile controls
Next-Generation Architecture
- Custom PCB
- Sealed, IP-rated switches
- Ruggedized enclosure
- EMC-conscious industrial electronics
- Replaceable battery architecture
My RoleProject Ownership
I conceived SR Comms in response to a communication problem encountered by Silent Racing's deaf drivers, and led its development across mechanical design, embedded hardware, firmware, Android application architecture, system integration, and field testing. The project progressed from an early functional prototype into a scalable native Android platform with off-grid and multilingual capabilities.
Software development used an AI-assisted engineering workflow, in which I defined the architecture, system behavior, interface requirements, integration logic, and validation criteria, while using development tools to accelerate implementation.
See It in Action
Silent Communications Interface
Vehicle-Side
Crew-Side
App Function:
Description
Assistive communication system replacing radios with BLE-to-SMS messaging for racecar drivers who are deaf and hard-of-hearing.
Steering wheel–mounted 11-button input interface transmits preset messages; dashboard device displays incoming crew alerts in high-visibility text.
Development
Programmed in MIT App Inventor (BluetoothLE API) and Arduino IDE for the Adafruit ItsyBitsy nRF52840 (BLE 5.0).
Integrated embedded firmware, Li-ion power management, and BLE communication into a compact steering wheel module.
Designed button/electronics housing in Fusion 360, with 3D printing for prototyping and CNC machining for final fabrication.
Implemented a trusted-numbers system for secure filtering and a hardware interrupt (Dismiss button) for safe acknowledgement.
Results
Delivered the first HMI comms system for deaf drivers, bridging embedded hardware and mobile app development.
Improved reliability and fault tolerance over traditional radios through BLE-to-cellular integration.
Validated in on-track functional testing, demonstrating low latency, robustness, and ergonomic usability under racing conditions.