B.O.S. — Boat Operating System

What B.O.S. Does

B.O.S. creates a central point from which the crew can monitor the condition of the boat and, where appropriate, control connected equipment.

The platform can display and manage information such as:

• Battery voltage, current, state of charge and historical consumption.
• Solar, alternator, shore-power and generator production.
• AC and DC loads.
• Freshwater, fuel and holding-tank levels.
• Bilge levels, pumps and high-water alarms.
• Temperature, humidity and machinery-space conditions.
• Navigation and NMEA data.
• Watermaker pressure, flow, TDS, production and alarms.
• Pump, relay and valve status.
• Equipment operating hours and maintenance intervals.
• Warnings, historical trends and remote notifications.

Each installation can be configured around the systems that actually exist onboard. A small sailing yacht may require only energy, tanks and navigation data, while a larger vessel may include several machinery spaces, multiple battery banks, watermakers, generators and distributed sensors.

A Modular Architecture

B.O.S. is built as a collection of independent modules rather than one monolithic application. Each function can be installed, configured and upgraded separately.

This modular structure makes it possible to:

• Start with a small system and expand it later.
• Integrate existing marine equipment instead of replacing it.
• Use standard sensors and communication protocols.
• Separate critical onboard control from optional cloud services.
• Maintain operation locally even when there is no internet connection.
• Rebuild or migrate the system without depending on one proprietary supplier.

The Onboard Hardware

The central B.O.S. computer is normally a compact, low-power Linux device such as a Raspberry Pi. It runs continuously onboard and communicates with sensors, instruments and controllers throughout the vessel.

Main Controller

A Raspberry Pi or comparable industrial single-board computer provides:

• Local data processing.
• Dashboard hosting.
• Historical data storage.
• Protocol conversion.
• Automation and alarm logic.
• Remote-access services.

The system can run from solid-state storage and be backed up as a complete, reproducible configuration.

Touchscreen Display

B.O.S. can be operated from a fixed onboard touchscreen. The interface is designed primarily for a wide landscape marine display, with large controls, clear status indicators and pages organised around practical onboard functions.

The dashboard may also be opened from:

• A laptop.
• A tablet.
• A smartphone.
• Another computer connected to the boat network.

Sensors and Input/Output Modules

B.O.S. can receive data from distributed input and output modules connected by robust marine-friendly communication links.

Typical connections include:

• Analogue voltage and current sensors.
• 4–20 mA industrial transmitters.
• 0–5 V and 0–10 V sensors.
• Digital inputs and alarm contacts.
• Relay outputs.
• Temperature probes.
• Pressure and flow sensors.
• Tank-level transmitters.
• Energy meters.

RS485 and Modbus RTU are particularly useful aboard a vessel because they allow multiple devices to share a reliable two-wire communication bus over long cable runs.

Navigation and Marine Data

B.O.S. can receive navigation and vessel data through standard marine communication systems.

Depending on the installation, this may include:

• NMEA 0183.
• NMEA 2000.
• Signal K.
• CAN bus gateways.
• Serial and USB instruments.
• Ethernet and Wi-Fi devices.

Typical navigation data includes:

• GPS position.
• Speed and course.
• Depth.
• Wind speed and direction.
• Heading.
• AIS targets.
• Engine and alternator information.

B.O.S. does not attempt to replace certified navigation instruments. Instead, it provides an additional integrated view and makes navigation data available to dashboards, logging systems and automation logic.

Watermaker Integration

Watermakers are one of the first major systems being integrated into the B.O.S. environment.

B.O.S. can receive and display:

• Feed and high-pressure readings.
• Product-water flow.
• Total water produced.
• Product-water TDS.
• Filter condition.
• Tank level.
• Flush status.
• Pump and valve status.
• Operating hours.
• Maintenance and fault alarms.

Where a compatible controller is installed, B.O.S. may also supervise commands such as starting, stopping, flushing and diverting product water.

The B.O.S. Software Stack

B.O.S. is built using established open-source software rather than one proprietary application. Each component performs a specific task and can be maintained or replaced independently.

Node-RED

Node-RED manages data flow, automation and system logic. It connects sensors, protocols, databases, dashboards and control commands through visual flows that are easy to inspect and modify.

It can be used for:

• Reading and converting sensor values.
• Applying calibration and alarm limits.
• Controlling relays and connected equipment.
• Creating operating sequences.
• Sending notifications.
• Connecting different communication protocols.

Signal K

Signal K provides a modern open data format for marine information. It collects navigation and vessel data and makes it available to dashboards, applications and other onboard services.

InfluxDB

InfluxDB stores time-series information such as battery current, solar production, tank levels, watermaker output and temperatures.

This allows the crew to see not only the current value, but also what happened during the previous hours, days or months.

Grafana

Grafana converts stored data into historical charts, gauges and analytical dashboards.

Examples include:

• Battery discharge overnight.
• Daily solar production.
• Watermaker production over time.
• Changes in TDS or pressure.
• Tank consumption trends.
• Engine-room temperature history.

MQTT

MQTT provides a lightweight messaging system between onboard devices and services. Sensors and controllers can publish their data, while dashboards and automation systems subscribe to the information they require.

Docker

The main software services can run in separate Docker containers. This keeps the system organised, simplifies updates and makes the complete environment easier to reproduce on replacement hardware.

One Interface for the Whole Boat

The B.O.S. interface is organised into practical sections rather than around individual equipment manufacturers.

Possible dashboard areas include:

• Home: Overall vessel status and active alarms.
• Energy: Batteries, solar, shore power, alternators and loads.
• Navigation: Position, wind, depth, heading and instrument data.
• Water: Freshwater tanks, watermaker and consumption.
• Machinery: Engines, pumps, temperatures and operating hours.
• Alarms: Active warnings, history and acknowledgements.
• Maintenance: Filters, service intervals and equipment runtime.

The interface can be adapted to each boat, hiding functions that are not required and giving priority to the information the crew actually uses.

Monitoring, Alarms and Diagnostics

B.O.S. is intended to make faults easier to identify before they become serious.

Instead of showing only a generic warning, the system can combine several related measurements.

For example:

• A falling battery voltage can be compared with current consumption and charger output.
• A watermaker pressure alarm can be compared with flow, filter condition and feed-pump status.
• A high machinery-space temperature can be linked to ventilation-fan operation.
• An unexpected tank-level change can be compared with pump status and flow-meter data.

Historical data also helps distinguish a real fault from a temporary condition and gives technicians useful information before they begin troubleshooting.

Remote Access

When an internet connection is available, B.O.S. can be accessed securely from outside the boat.

This can make it possible to:

• Check battery and charging status.
• View temperatures and alarms.
• Confirm that onboard computers remain online.
• Inspect historical charts.
• Support troubleshooting remotely.
• Access configuration and maintenance tools.

Secure private networking solutions such as Tailscale can provide remote access without exposing sensitive onboard services directly to the public internet.

Local First, Cloud Optional

B.O.S. is designed around a local-first philosophy.

The onboard system should continue to operate when:

• The boat has no internet connection.
• The marina Wi-Fi is unavailable.
• A cloud service is temporarily offline.
• The vessel is offshore for an extended period.

Remote servers may be used for development, backups, demonstrations or optional external access, but the essential onboard functions remain local to the vessel.

Open Source and Rebuildable

B.O.S. is being developed as an open and reconstructable system.

The objective is to avoid a situation where the boat depends permanently on:

• A discontinued proprietary display.
• A closed subscription service.
• One specific installer.
• An undocumented configuration.
• Hardware that cannot be replaced.

Source code, configuration files, dashboard definitions and installation documentation can be version-controlled and backed up. If hardware fails, the system can be rebuilt on a replacement computer rather than recreated from memory.

Designed for DIY Builders and Professional Installations

B.O.S. is intended to remain accessible to technically minded boat owners while also supporting professional, repeatable installations.

A DIY builder can begin with:

• A Raspberry Pi.
• A touchscreen or browser.
• A few sensors.
• Standard open-source software.

A professional installation can extend the same architecture with:

• Industrial input and output modules.
• RS485 field networks.
• Marine-certified gateways.
• Redundant power supplies.
• Protected enclosures.
• Remote service and structured backups.

The principles remain the same: standard protocols, clear documentation, modular components and local control.

What B.O.S. Is Not

B.O.S. is not intended to replace every specialised marine device aboard the vessel.

It is not:

• A substitute for certified chartplotters or collision-avoidance equipment.
• A replacement for local mechanical and electrical safety systems.
• A reason to remove manual overrides.
• A cloud-dependent remote-control gadget.
• A closed black-box product that only one company can service.

Its role is to connect, organise and clarify the information already present onboard while adding intelligent monitoring and carefully designed control where it provides a real benefit.

The Long-Term Vision

B.O.S. is CobrAm’s long-term project for a more transparent, maintainable and intelligent onboard environment.

The goal is not to add electronics merely for the sake of technology. The goal is to make the boat easier to understand.

A well-designed B.O.S. installation should help the owner answer practical questions immediately:

• Where is the energy going?
• Why is the battery not charging correctly?
• How much water did the watermaker produce today?
• Is a filter becoming blocked?
• Has a pump been running unusually long?
• Is the boat safe while nobody is onboard?
• What changed before an alarm occurred?