It has been several weeks since the team was last on water, performing test sessions. And for a good reason: the Syroco speedcraft prototype was in the workshop, undergoing extensive maintenance and upgrades to many of its systems. Last week, the team was excited to unveil the new version of the prototype, and is now getting ready to restart test campaigns.
From the outside, it does not look that different, but inside is another story.
Design, build, test, and iterate… 106 times (so far)
Of course, everyone wishes they get a design to work perfectly the first time around. Unfortunately this rarely happens. At Syroco we therefore adhere to a time-proven principle of agile startups: fail fast, learn fast. As soon as practical, when a system is operative, we’ll put it to the test. It will seldom work perfectly from the get go. But through precise analysis of its performance and its failures, we learn how to improve it, and whether it works at all.
Several months of tests on the first version of the prototype did just that. After 106 test runs performed with a 51% success rate, we learned that some systems worked well, some others needed an upgrade, and also of a few that needed to go back to the drawing board. Below are some examples.
Low speed stabilisation: introducing the LS3
As a reminder, the aile d’eau design we have chosen for our speedcraft is the most efficient way to use the power of the wind. But we always knew that the transition to high speed, from archimedean navigation to stable flight; would be a big challenge. This was confirmed by many tests during which it was difficult to control the attitude of the prototype.
To alleviate this issue, the team designed a new system, dubbed LS3 (Low Speed Stabilisation System). From the outside, it shows as a thin red line that attaches the nose of the prototype to the kite lines. Inside, there is a complex tension and winding system that maintains the correct force to keep the prototype stable.
Decreasing drag: a new design for the shaft of the foil
Our initial designs (including some we use in our computer renderings) represented the shaft as a profiled appendix. Early in our tests, we decided to start with a circular and flexible shaft because it was easier to operate and faster to build. In the version we just released, we upgraded the shaft to increase its resistance and streamline the control wiring it contains. The new shaft is now less than 5 millimetres in diameter, and yet can take forces in excess of 800 kg. New wiring, built into that shaft, will provide for faster and more accurate foil control.
Improving communications: new transceivers and antennas
During some tests, we have experienced loss of communication with the onboard systems. This situation, caused by unexpected attitudes of the prototype resulting in immersed antennas, made us lose some test data but also highlighted a potentially dangerous situation: the inability to remotely trigger emergency release systems should it become necessary.
In this new version of the prototype, the team added redundant transceivers and antennas to ensure that no matter the attitude or position of the speedcraft, all control and data channels would remain operational.
Better maintainability: complete electronics & wiring overhaul
After months of adding or modifying onboard electronics, the Electronic Control Unit had become somewhat cluttered, and the overall prototype wiring was challenging to understand and maintain. As a reminder, since our prototype is radio controlled, all command systems are driven by electronics in this phase.
The team decided to rebuild from scratch the entire architecture of the electronics and wiring. This is probably one of the least visible improvements, but we know that it will greatly increase the reliability and maintainability of the prototype. No less than 150 metres of cable were required, in our 2.4 metres one-third-scale speedcraft!
And now, let the new test campaigns begin…
This unveiling was of course an important milestone for the team, with the entire company in attendance. It was also an opportunity to share some pizzas and drinks, like startups do when they celebrate! And now to the next steps: sea trials are ready to resume. If you come near Marseille, be on the lookout…