SailingKSF Autopilot Suite

Why This Project Started

The project started with a simple frustration: many commercial autopilots hold heading by chasing the rudder hard through basic PID-style control. Offshore, that can mean more wear, more noise and more fatigue.

We wanted a different approach. First understand how the boat is really moving in the waves, then steer with anticipation so rudder use becomes calmer, cleaner and closer to the way an experienced helmsman would drive.

If you have hand-steered in a seaway, you have probably felt the boat return near the same heading and track after a full wave cycle. This sea-aware autopilot is built around that idea: work with the sea where possible, and only correct when a real correction is needed.

• Less rudder hunting and fewer violent corrections.
• More predictable course-keeping as sea states change.
• More confidence during short sleep periods on singlehanded passages.

I have worked professionally with software for many years, and because I also enjoy microcontroller programming and sailing, this became a natural project for me.

Network And Compute Architecture

• All modules interoperate over standard NMEA2000 for marine compatibility.
• Every hardware module has its own local touch display: a 4.0-inch TFT on each module, except the Main unit, which uses a 7-inch helm display.
• Multilingual support is built into every module, including UI/LCD and iPad workflows.
• The system is designed to work with current sensors, wind/log instruments, rudder command units and related components from Raymarine, Garmin, Simrad and other NMEA2000-capable ecosystems.
• Inside the autopilot control cluster, core nodes communicate over a private high-speed NMEA channel for deterministic control-data flow.
• Current high-speed core topology: 3x Teensy 4.1 + 1x ESP32-WROVER.
• Gateway and UI layers connect the private control network with standard boat-network context.

Current hardware deployment is 7x Teensy 4.0, 3x Teensy 4.1 and 2x ESP32-WROVER. The active module stack now exceeds 240,000 lines of code, excluding external libraries, and the iPad app alone adds more than 20,000 lines.

Operational Modes, Including WORK And RACE

• STBY, HDG, WIND and CRS/TRK cover normal passage handling.
• WORK mode prioritizes boat stability, making deck and sail handling safer during high-workload moments.
• In WORK mode, stability can take priority over strict course-holding, so short off-course drift is acceptable when it improves safety on board.
• RACE mode is the active performance profile for faster sailing toward a heading, mark or calculated course-to-steer. It keeps the skipper in command while giving more active course advice, earlier trim/tactical recommendations and clearer performance tradeoffs.
• RACE:HDG can be used without a waypoint for a fast run on a captured heading. RACE:MARK and RACE:CTS become relevant when a waypoint, mark, bearing or course-to-steer solution is available.
• Critical transitions stay acknowledged and visible.

Traffic And Hazard Awareness

• AIS/RADAR warnings and alarm flows are shared across the helm UI, iPad app and voice system.
• An avoid-and-resume route workflow supports temporary tactical deviations.
• Hazard cues from attitude and force sensing can trigger advisories or prevention logic.
• The goal is to keep the skipper in command while reducing reaction delay.
• Barometric pressure trend, wind shift and gust fusion can give earlier squall warnings, which is especially useful during night watches.

Open the sailing safety article library.

iPhone Timer App

The iPhone timer app is under test as a companion to the watchkeeping timer system. It does not create a separate alarm world on the phone. It works with the same timer state shown on the helm UI display and on the dedicated timer modules.

Start, snooze, acknowledge and reset commands are intended to stay synchronized, so the skipper can use the nearest screen without losing track of which timer is active. Push notifications are supported so important alarms can still arrive when the phone is locked or in sleep mode.

Waveshare Timer Unit

A Waveshare-based timer unit is also under test. It is battery powered and uses the onboard WLAN, which makes it practical to carry around the boat during rest, checks or work away from the helm.

Even when carried as a portable unit, it still behaves as one timer module in the shared system. It talks with the other timer modules on the network and mirrors the same watch alarm state instead of running its own isolated countdown.