Displayless Onboard Data Hub Using Crew Smartphones as Marine Displays
Defensive Prior Art Disclosure
Displayless Onboard Data Hub Using Crew Smartphones as Marine Displays
Statement of Intent
This document is published as a defensive prior art disclosure.
The author intentionally makes the technical concepts, systems and methods described below publicly available so that they may be considered prior art against later patent applications seeking to monopolize the disclosed subject matter.
The disclosure is intended to be sufficiently detailed to allow a person skilled in embedded electronics, marine instrumentation and networked software to implement the system without undue experimentation.
No exclusive patent rights are asserted by the author over the concepts expressly disclosed in this publication.
Technical Field
The disclosed subject matter relates to:
onboard computers for boats and other watercraft;
marine sensor and instrument integration;
displayless or headless embedded devices;
local wireless distribution of vessel data;
smartphone-based marine user interfaces;
retrofit monitoring of older vessels;
operation without Internet connectivity.
Background and Technical Problem
Conventional marine chartplotters and multifunction displays integrate a processor, a marine network interface and a dedicated sunlight-readable display in one enclosure. This arrangement increases cost, physical size, heat generation and energy consumption.
Many small vessels already carry several capable displays in the form of the crew members' smartphones or tablets. Nevertheless, each of these devices normally operates as a separate consumer device and does not have direct access to the vessel's NMEA data, discrete electrical signals or local sensors.
A further problem occurs on inland waters and remote waterways where Internet access may be intermittent or unavailable. A cloud-only application cannot reliably provide current vessel data under such conditions.
Summary of the Disclosed Solution
The disclosed system is a displayless onboard data hub installed on a watercraft. The hub acquires data from onboard and external sources, normalizes the data into a common state model and makes the state available to one or more crew smartphones or tablets through a local network.
The hub does not require its own permanent graphical display. A temporary service display or indicator LEDs may be used, but the normal user interface is rendered by devices already carried by the crew.
The system continues to operate locally when no Internet connection is available.
System Architecture
An exemplary implementation comprises:
an embedded processor or microcontroller;
non-volatile storage;
a GNSS receiver or an interface to an external GNSS source;
one or more marine network inputs, including NMEA 0183 or NMEA 2000;
optional isolated discrete electrical inputs;
optional local sensors, including an inertial measurement unit, temperature sensor, atmospheric pressure sensor or battery monitor;
a local wireless communication interface;
a local application server;
a browser-based or native client used on crew devices.
The processor may be an embedded Linux computer, a real-time microcontroller, a system-on-module or a combination of a low-power controller and a more capable application processor.
Read-Only Marine Network Interface
In one embodiment, the hub is connected to an NMEA 2000 network through an electrically isolated CAN interface configured for passive or read-only operation.
The hub receives parameter group messages representing, for example:
geographic position;
speed and course over ground;
vessel heading;
engine speed and temperature;
fuel level and fuel consumption;
water depth;
wind speed and wind direction;
battery voltage;
rudder or trim state.
The read-only configuration prevents the hub from issuing control commands to propulsion, steering or safety-critical devices. The same principle may be applied to NMEA 0183 by using an isolated receive channel.
Retrofit Discrete Signal Inputs
Older vessels may not expose lighting, ignition, pump or windlass state on a digital marine network. The hub may therefore include galvanically isolated inputs connected in parallel with selected 12-volt or 24-volt circuits.
An input can determine whether voltage is present on a circuit without controlling that circuit. Suitable interfaces include optocouplers, isolated comparators or protected resistor and transient-suppression networks.
The detected state may represent, for example:
port navigation light active;
starboard navigation light active;
stern or masthead light active;
engine ignition active;
bilge pump active;
anchor windlass active;
cabin supply active.
Common Vessel State Model
Data from heterogeneous sources is converted into a common state model. Each value may include:
a semantic identifier;
a value and unit;
a source identifier;
acquisition time;
validity or freshness information;
optional quality information.
For example, `navigation.speed_over_ground` may be supplied by a local GNSS receiver or by an NMEA message. The client application does not need to know which physical source supplied the value.
If two sources provide the same quantity, the hub may select one according to a fixed priority list, validity flags or freshness.
Local Application and Data Distribution
The hub provides a local network service reachable by crew devices. In different embodiments the service may use:
a Wi-Fi access point created by the hub;
an existing onboard Wi-Fi network;
Bluetooth Low Energy characteristics or notifications;
a wired Ethernet connection;
a combination of the above.
The user interface may be a progressive web application stored and served entirely by the hub. The first connection downloads the application assets from the local server, not from the Internet.
Live data may be delivered using WebSocket, server-sent events, UDP multicast, Bluetooth notifications, a publish/subscribe protocol or periodic HTTP requests.
Multiple phones may receive the same vessel state simultaneously. Different users may select different dashboards, languages, units or alarm preferences without changing the underlying acquisition system.
Offline Operation
Charts, checklists, recent weather information, manuals and route information may be cached locally. Core functions do not depend on DNS resolution, cloud authentication or a remote server.
When Internet connectivity becomes available, the hub or a crew phone may optionally synchronize selected data with an external service. Loss of that connection does not interrupt local acquisition or display.
Example Operating Sequence
The hub starts when vessel power is applied.
It initializes the marine bus receiver, GNSS receiver and discrete inputs.
Received measurements are decoded and entered into the common state model.
The hub advertises or exposes a local communication service.
A crew member connects a phone and opens a local address or installed PWA.
The phone receives current navigation and vessel-status data.
Additional crew members connect and choose their own dashboard layouts.
If the external Internet connection is lost, the local service continues to operate.
Failure Handling
If a source stops producing data, its values are marked stale rather than silently held as current. A client can display the age of the last valid measurement.
If the primary GNSS source becomes invalid, a secondary source may be selected. If the local network is temporarily unavailable, acquisition continues and recent events may be buffered for later delivery.
Variants
The disclosed hub may be:
permanently installed or portable;
powered from the vessel supply or an internal battery;
used on motorboats, sailing boats, kayaks, rental pedal boats or workboats;
integrated into a waterproof enclosure;
combined with a dedicated emergency display while retaining smartphones as additional screens;
used solely as a receiver and monitor or extended with separately authorized control outputs.
Technical Effects and Advantages
The system provides:
elimination of a mandatory dedicated display;
lower hardware cost;
reduced installation space;
reuse of devices already carried by crew members;
simultaneous personalized displays for several people;
integration of modern digital sensors with legacy electrical circuits;
continued operation without Internet access;
separation of safety-critical vessel networks from user-facing clients.
Technical Concepts Disclosed for Prior Art Purposes
This publication expressly discloses:
a displayless onboard marine data hub using smartphones or tablets as primary displays;
local offline delivery of normalized NMEA and sensor data to multiple crew devices;
a read-only marine bus interface combined with isolated discrete voltage-state inputs;
a locally served PWA or equivalent application that remains usable without the Internet;
per-user dashboards generated from one common vessel state;
freshness, validity and source metadata associated with onboard measurements;
operation of the above system on small recreational or rental watercraft.
Public Availability Declaration
The concepts expressly described in this publication are made available for public implementation, modification and extension. The purpose of publication is to prevent later claims that these broad concepts were undisclosed or unavailable to a person skilled in the art.