Enhanced with digital technologies, a ‘smart boat’ is a vessel with remote and onboard control, monitoring, and management of systems, writes Rob Ferenczi.

One of the great things about converting my boat is that it doesn’t require extensive technical knowledge.

I chose the easiest route which is within the capabilities of most DIY-ers. It also cost me less than £400, which includes the computer, router, and many of the sensors.

Smart boat: Virtual switches

One of the fundamental aspects of a smart boat is virtual switches. These switches control various devices on board through a digital interface.

The best part is you can retain your manual switches alongside the virtual ones for added convenience.

My virtual switches are on my tablet, but you could use your phone. In total, I have six virtual switches.

The beauty of these virtual switches is that once you’ve set them up, you can use automation so they can perform tasks automatically.

I have one for an anchor light, which turns on the anchor light at the top of the mast.

I’ve added automation so it turns on the anchor light at sunset and turns it off at sunrise; it has also been programmed to remain off when the boat is moving or sailing.

Deck lights are useful when returning to your boat in the dinghy at night. I can turn on my deck lights from the dinghy so the decks are lit when I arrive.

You can also set them so they automatically sense it’s night and turn on as you approach.

I also have an outdoor siren to scare off intruders or birds or alert other sailors near my boat. I have a virtual switch for the bilge pump.

The bilge pump is normally started or activated by a float switch.

But if I am on land and receive a notification from my boat that there’s water in the bilge, I can start the bilge pump from wherever I am.

This is a good backup if the float switch isn’t working.

The indoor siren is used to notify people on board of a condition that needs attention; it has nine different melodies, and the volume is all adjustable via the virtual switch.

And finally, I have a watermaker virtual switch, which is programmed to flush the system at 0900 daily.

Smart boat: Instruments

With this system, I can monitor my boat’s instruments from my phone or tablet when I’m away or on board.

This feature has proven incredibly useful. I can set up customised alerts and alarms, such as depth and wind speed alarms, and even monitor changes in the wind direction.

When sailing, I set up alerts based on as many of the boat’s instruments as I like.

For example, if my boat is steering to an angle to the wind, I can set an alert to ensure the boat stays within a range of compass headings.

Or if I’m steering to a compass heading, I can be alerted if the wind changes direction or is higher or lower than a preset wind speed.

You can get really sophisticated and set up an alert when it’s time to reef the sails with different wind speed limits, depending on whether you’re close hauled or on a broad reach.

We can put in our normal criteria for reefing sails, and it will remind us.

Also, you can specify how long the wind speed has been exceeded to filter out infrequent gusts.

I can also specify how long the boat has been off course to filter out falling off waves etc.

I’ve sailed more than 80,000 miles around the world, and I find these instrument-based alerts extremely useful.

My physical instruments also provide warnings, but they’re not as sophisticated. They usually just emit a little beep sound.

With my system, I can activate a siren with a choice of different tunes and volumes depending on the alert.

And with text-to-speech, the ‘smart boat’ system can talk to me via speakers.

Smart boat: Anchor monitoring

Traditional anchor-watching apps often suffer from issues like losing GPS signals and false alarms, but my anchor system integration eliminates these problems by utilising the boat’s high-quality GPS.

With this setup, you can monitor your anchored position on board or remotely, and even trigger alarms through indoor sirens or the ship’s horn, ensuring maximum safety and reliability.

Additionally, the same system acts as a boat tracker, allowing me to locate my boat if it were taken without my permission.

The anchor monitor also has the optional ability to automatically post position reports online so family and friends can follow your adventures.

Smart boat: Safety features

For me, safety is paramount. I’ve taken additional measures to protect my boat by installing five wireless water leak sensors in critical areas, such as the bilge, near seacocks and water pumps.

Even on board, I can be aware of water and leaks before I see evidence of water ingress.

This early warning can provide valuable time to locate and address the source of a leak, as it becomes more challenging once it’s above the floorboards.

Furthermore, I’ve incorporated a wireless fire alarm sensor. This additional safety measure ensures early detection of potential fire hazards.

Smart boat: Engine monitoring

I’ve set up an oil pressure sensor and four temperature sensors around the boat to monitor the cooling temperature, the temperature near the thermostat, the raw water elbow temperature, and the alternator temperature.

This allows me to receive early warnings well before the engine reaches a critical state.

For example, the temperature at the raw water elbow on my boat is normally between 38°C and 40°C.

If it rises to 42°C I’m notified by an alert, which could indicate a problem such as a worn water pump impeller or no water flow at all.

The alternator temperature sensor is particularly useful, especially if you use lithium-iron phosphate batteries which work the alternator harder.

Furthermore, you can review historical data on engine temperature and oil pressure trends.

This feature allows you to track and analyse how these parameters feature over time, providing valuable insights into the performance and health of your boat’s engine.

Digitising analogue gauges

You can digitise any existing analogue gauges, such as fuel tank levels, water tank levels, engine coolant temperatures, and engine oil pressure, by monitoring the existing resistance-based sensors and integrating them with digital systems.

The Raspberry Pi 4

The core of my ‘smart boat’ system is the compact Raspberry Pi 4 computer. Upon purchase, it is provided as a bare circuit board.

Additionally, it comes with a case for protection, a micro SD card for data storage, and optional heat sinks for thermal management.

An optional cooling fan is available for enhanced temperature control, along with the necessary USB Type-C power cable.

For this setup, I used the Raspberry Pi 4B model equipped with 8 gigabytes of RAM.

Raspberry Pi Overview

Although these circuit boards are pretty tough, it is best to hold them by the sides rather than the middle to avoid static electricity damage.

Let’s quickly examine the Raspberry Pi 4B. This model offers four USB ports: two blue USB-3 ports, which are the newer and faster version, and two standard USB-2 ports.

One of the USB-3 ports will be used to connect all the wireless Zigbee sensors for the bilge, fire, siren and other functionalities.

The other USB port will connect our boat’s instrumentation using the NMEA protocol.

To the right of the USB ports is an ethernet port, which connects the ethernet cable to the 4G LTE router.

On the side of the Raspberry Pi, we have a power port that requires a USB Type-C cable to supply 5V of power.

There are two micro HDMI ports, though we won’t use a dedicated display in this setup. There’s also a standard audio port and a micro SD card slot.

On the circuit board, there is the CPU, the RAM, the ethernet controller, and the USB port controller.

Installing heat sinks

Heat sinks are unnecessary unless you plan to drive the Raspberry Pi hard.

However, I have installed them on top of the ethernet controller, USB controller, and a combined heat sink and fan on the CPU.

Each heat sink has a bit of sticky 3M double-sided tape on the bottom. It’s easier with smaller fingers or tweezers.

Apply slight pressure to ensure it’s in place without applying too much force.

Fan Installation

I use a fan with an integrated heatsink. Orient the cable so they’re facing the pins on the far side and place it on top of the CPU, applying a bit of pressure downwards.

The fan can run at 5V for maximum speed, with the red cable going into the second pin from the end and the black cable into the third pin.

It can also run at 3V for a quieter operation.

The case

It is best to use the official case for the Raspberry Pi. Ensure the orientation matches the ports on the Raspberry Pi, and then place the circuit board inside, pressing it down into the four plastic notches at the bottom.

The top clicks on easily and, once assembled, it presents a neat and compact computer that powers your entire boat.

The micro SD card inserts with the metal contacts facing upwards, and it doesn’t click when fully inserted – just push gently until it stops.

The 4G LTE router

A 4G LTE router serves three essential purposes for our ‘smart boat’.

Firstly, it sends alerts and notifications to our smartphones while ashore.

Secondly, the router allows us to remotely monitor and manage our boat. With the help of the 4G connection, we can access our ‘smart boat’ app to check real-time data such as instruments, boat location, or camera feeds.

Lastly, the 4G LTE router serves as the onboard wifi network, enabling crew members to access the internet and allowing communication between all our devices on the boat.

The router I have here is a TP-Link MR6400. It costs about £60. I have used this for the last three years, 24 hours a day.

I have sailed to many different countries, and it has performed flawlessly.

Smart boat software

At the heart of the ‘smart boat’ system, I have selected Home Assistant (HA), a popular open-source software used for ‘smart homes’ on land.

I have customised it specifically for use on a boat. Here are the initial steps of installing Home Assistant on a Raspberry Pi.

Step 1 Preparations

• Raspberry Pi (3 or 4 depending on your choice)
• Micro SD card (32GB A1 recommended)
• Micro SD card reader
• Windows 10 PC/laptop or Mac
• Internet connection

Step 2 Downloading Raspberry Pi Imager

1. Visit the Raspberry Pi official website at www.raspberrypi.org/software to download the Raspberry Pi Imager.
2. Choose the version of the Imager compatible with your operating system (Windows or Mac) and initiate the download.
3. Run the Raspberry Pi Imager once downloaded.

Step 3 Selecting Home Assistant Image

1. In the Raspberry Pi Imager interface, choose the operating system by selecting ‘Other specific purpose OS’.
2. Navigate to ‘Home Automation’ and click on it.
3. Select ‘Home Assistant’. You will be presented with two options, one for Raspberry Pi and another for Raspberry Pi 3. Choose according to your Raspberry Pi model.

Step 4 Flashing Home Assistant onto the micro SD Card

1. Insert your micro SD card into the PC using the micro SD card reader.
2. In the Raspberry Pi Imager, go to the storage section and select your micro SD card. Ensure it’s the correct one to avoid data loss.
3. Click on ‘Write’ to start the flashing process. Confirm any prompts to erase data on the micro SD card.
4. The writing process will take some time (5-20 minutes) depending on your internet connection and computer speed. Wait until the process is completed.

Step 5 Final steps before booting

1. Once the flashing process is complete, Windows might prompt you to format the micro SD card. Select ‘Cancel’ as the necessary files are already correctly formatted on the card.
2. Safely eject the micro SD card from your computer.

Step 6 Setting up the Raspberry Pi

1. Insert the micro SD card into your Raspberry Pi.
2. Connect the Raspberry Pi to your network with an ethernet cable.
3. Plug in the power supply to boot the Raspberry Pi.
4. Allow a few minutes for the Raspberry Pi to boot up.

Step 7 Accessing Home Assistant

1. On a computer connected to the same network, open a web browser and navigate to http://homeassistant.local:8123/
2. If the address does not work, you may need to find the Raspberry Pi’s IP address through your router’s interface and use that to access Home Assistant.
3. Access Home Assistant and you’ll see a ‘Preparing Home Assistant’ screen. This indicates the software is initialising, which can take up to 20 minutes. Please wait patiently during this setup phase.
4. Once Home Assistant is ready, you’ll be greeted with the onboarding form page. Follow the prompts to set up your account; name your Home Assistant installation with your boat’s name, for instance, and configure the basic settings such as country, language, timezone, etc.

Adding the physical sensors

The advantage of Home Assistant as the base for the ‘smart boat’ system is the plethora of inexpensive, easily integrated off-the-shelf sensors.

Virtual Switches

To set up an existing device, eg anchor light, to be controlled by a virtual switch and enable automatic on/off functionality,

I use the Shelly 1 relay. The Shelly 1 is a well-engineered, wifi-controlled relay switch commonly used in home automation.

It has a huge following and integrates easily with Home Assistant, via a Shelly Home Assistant integration.

The Shelly 1 costs around £15. There are also other cost-effective options such as an eight-switch relay board which costs about £30.

This can be integrated with Home Assistant using the add-on ESP Home.

Zigbee wireless devices

A low-power network is needed to easily add the sensors; I use a Zigbee USB coordinator or dongle.

This allows you to add battery-powered sensors, such as bilge water monitors, fire or smoke sensors, intrusion alarm sensors, warning sirens, temperature/humidity sensors, and many more.

Zigbee is a low-power wireless communication protocol specifically designed for smart homes. Zigbee provides a network with extremely low power consumption, ensuring that Zigbee sensors enjoy extended battery life.

Typically, batteries in Zigbee devices last one to two years.

In contrast, other wifi devices tend to consume more power, which can lead to shorter battery life for connected devices.

Additionally, installing battery-powered Zigbee devices is quick and simple.

For example, you can install four bilge high water sensors in your boat’s bilge in less than an hour.

Attempting the same with cable-powered devices would take days, considering the challenges of routing cables and connecting them to the boat’s direct current (DC) power.

Wireless engine sensors using ESP32

Many DIY sensors can be set up cost-effectively using a remarkably versatile ESP32 microprocessor.

This compact yet powerful device will serve as the foundation for a series of innovative ‘smart boat’ projects including engine temperature and oil pressure monitoring, energy analysis, wireless instrumentation interfaces, pump activity alerts, fluid flow sensors, tank level indicators, and even solar panel and battery monitoring.

This ESP32 is a remote hub, equipped with numerous ports to connect a range of sensors.

It will collect data from these sensors and transmit it wirelessly to our central system, the Raspberry Pi running Home Assistant.

The best part? It’s energy-efficient and incredibly affordable. Each ESP32 is only about £5. For example, I have set up an ESP32 near the engine to monitor four engine temperatures and oil pressure.

The ESP32 is wirelessly integrated into Home Assistant using the ESP Home add-on.

NMEA connections

Typically, boats feature two main types of instrumentation networks: the NMEA 0183 and the NMEA 2000 networks.

The older 0183 network is essentially a simple serial network based on the RS232 or RS422 standards.

On the other hand, the 2000 network is a more contemporary system built on the Control Area Network (CAN) bus, similar to what’s present in modern automotive vehicles.

I’ve developed Home Assistant integrations for both 0183 and 2000 networks. The integrations automatically generate and populate entities in Home Assistant based on the instrumentation data from the NMEA network.

Even if you add instruments in the future, they will appear automatically within Home Assistant.

To connect to a 0183 network, you can use a serial-to-USB adapter or via wifi.

To connect a 2000 network you can use a CAN USB adapter or via wifi with an ESP32 microprocessor.

Conclusion

Transforming my boat into a smart vessel for less than £400 has been a rewarding journey which demonstrates the accessibility and cost-effectiveness of incorporating digital technology into maritime environments.

I’ve significantly enhanced the safety, efficiency, and convenience of my boat.

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