A bike computer built on the LilyGO T-RGB: a round 480×480 touch display, ESP32-S3 with BLE and WiFi, SD card, and a LiPo charger on board. It reads standard BLE bike sensors, shows turn-by-turn navigation from your phone, logs every ride to SD card and rates the road surface with its own accelerometer.
Display -- "Rim & Ridge" UI (LVGL 8, designed in EEZ Studio)
- Main screen: speed with average marker on the outer ring, cadence, temperature, altitude, gradient, heart rate with zone band, distance, ride time/clock, driving state (pedalling / coasting / stopped / break), road-quality indicator, status icons for WiFi, GPS fix and battery
- Navigation screen: opens by itself when the next maneuver comes close, closes after it. Shows large turn arrow, distance ring, street name, next maneuver, lane guidance and roundabout exits
- Tap the nav pill to open it manually, swipe right to close it
Sensors
- BLE: cycling speed & cadence (CSC), heart rate, battery level of each sensor; sensors are paired once and locked to their address
- I²C: BME280 (barometric altitude and gradient, temperature), BMI160 accelerometer
- Forumslader hub-dynamo charger via my
BLE gateway (build variant
-FL)
Navigation and GPS from the Android companion app TrailBridge, which forwards OsmAnd's turn-by-turn instructions and the phone's GPS position over BLE (protocol).
Road quality from the BMI160 at 400 Hz: roughness class per interval, shock detection (with second peak from the rear wheel), a calibration ride on smooth asphalt, and gradient from the accelerometer as an alternative to the barometer.
Logging
- Binary ride log on SD card: ride data every 5 s incl. GPS, road quality per interval, every shock; raw accelerometer captures on demand
- Debug log and raw Forumslader log (replayable on the device)
Tools/: Python CLI to convert logs to CSV and GPX (sensor data as Garmin TrackPointExtension, shocks as waypoints) and a small upload/archive service
Web interface (when on WiFi)
- Download, replay and delete log files; live log with adjustable log levels
- Ride statistics and charts, odometer and wheel calibration
- Manage BLE sensors, sensor and accelerometer debug pages, calibration
- Firmware and filesystem update over the air
Serial console with line editing, history and Tab completion: log levels, memory/stack report (mem), road-quality settings
(rq), log replay.
- LilyGO T-RGB (the two builds differ in the touch controller variant,
TRGB_ROUND/TRGB_OVAL, and in Forumslader support) - Optional: BME280 and BMI160 on the I²C bus
- LiPo battery
- 3D-printed case and handlebar mounts -- a parametric model for the Canyon CP0007
gravel cockpit is in
cad/
PlatformIO, Arduino framework (pioarduino platform):
pio run -e trgb-esp32-s3 -t upload # default: BLE + I²C sensors
pio run -e trgb-esp32-s3-FL -t upload # Forumslader variant
pio run -e trgb-esp32-s3 -t uploadfs # web interface files (data/site)trgb-esp32-s3-ota and trgb-esp32-s3-FL-ota are the same builds, uploaded over WiFi
to the device's /update endpoint. Target is TRGB-BC.local; if mDNS doesn't resolve,
pass the IP: pio run -e trgb-esp32-s3-ota -t upload --upload-port 192.168.x.y
The build applies small patches to two libraries (apply_patches.py), which needs
the patch tool.
- ROADMAP.md -- open work and ideas
- doc/PITFALLS.md -- hardware and framework pitfalls (PSRAM and display flicker, NimBLE, internal heap, ...) -- German
- doc/design/rim-ridge-design-system.md -- UI design system -- German
- doc/DEBUG.md -- serial console, logging and core dumps
- Tools/README.md -- log format and tools -- German
Contributions are welcome, see the roadmap for where help is wanted.