Voyager Series

100 days on a Beach - 6th Bass Strait Voyage

100 days on a Beach and a broken leg - 6th Bass Strait Voyage  The 6th voyage on Bass strait for Voyager 2.7, commenced from Torquay Fisherm...

Saturday, 1 January 2000

Voyager Series - Small Ocean Vessels

Voyager Series - Small Ocean Vessels - Overview

Voyager 2.0
This is a small prototyping platform for autonomous ocean going vessels.
The aim is to develop and test the technologies necessary for a small sailing vessel that can sail for an indefinite period of time, navigating a course of predefined waypoints.

The hull is fibre glass covered foam, similar to a surfboard, and is intrinsically buoyant.
The sail is a self-trimming wingsail, which is good solution for autonomous vessels due its low power consumption, and ease of operation.
The vessel is controlled by several on-board microprocessors that are responsible for navigation, controlling the sail, and steering. These are all Arduino devices.



Currently the vessel can successfully navigate a set of waypoints as shown in the example track below.



The wingsail is mounted using ball-bearing races and can freely rotate 360 degrees.
The wingsail trim tab is controlled electronically by the main computer using a Bluetooth link.




Voyager 1

The first Voyager was a simple boat with Vane Self Steering, designed to sail downwind, with the wind on the starboard quarter.
It was fitted with satellite tracking that was developed to report the boats position every 4 hours via the Iridium satellite network.
  

It was launched in 2016 from a beach in eastern Victoria, with favourable winds to take it well offshore. and hopefully well out into the Tasman Sea.
The Launch

The first Voyager sailed and drifted for a month, out into the Tasman sea, until it finally went quiet a few miles from Lord Howe Island.



It was likely that Voyager 1 sank after a period of one month at sea due to the use of expanding spray foam for bouyancy. This is an open-cell foam that eventually takes up water.

Voyager 1.5

The next iteration of Voyager was basically the same again, but with some updates to address the perceived failing of Voyager 1. Specifically changing to use a closed cell foam for bouyancy.
It was also steered by Wind Vane, and configured for sailing with the wind on the starboard quarter.



Voyager 1.5 was launched from the same location in eastern Victoria, in June 2018.
It sailed around eastern Bass Strait with the wind, for about three weeks, and then went quiet as it headed out into the Tasman with a strong Westerly wind.


After about seven months, I received a message and photographs of Voyager 1.5 from Northern NSW.


After studying the images of the Voyager 1.5 provided after its recovery, its seems likely that the aluminium fin keel bent around 90 degrees during the gale conditions when the last signal was sent. The fin is 3mm aluminium bar. Its likely that the satellite transmitter was pointing sideways into the water, and hence no signal could be received.
It may have continued transmitting like this for several months.

By coincidence the account for this satellite tracking device was discontinued only a few days before news was received that the boat was found.
The images show that the tie-down cord used for retaining the satellite transmitter appear to have been cut, and the device possibly removed as a curiosity for the first person who found it.
We'll never know if it was still transmitting at that time, because it was right on the edge of the predicted battery life, but it's unlikely.

Given the location of the vessel, it appears to have gone against East Australian Current (EAC) to wash up on a beach in Northern New South Wales. Hence it seems likely that it drifted out in to the Pacific with the EAC and came into the Australian coast well north, before washing ashore.





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