From the associated article on Spindrift Racing's website:
Designed for crewed sailing, the maxi-trimaran Spindrift 2 has never had autopilot. A small revolution has taken place on board since the decision to compete in the Route du Rhum. It is a fact that, sailing solo, Yann cannot be on the helm 24 hours a day. He has to sleep, and eat, but he also has to set the sails, make manoeuvres, or work on the computer on board, so, needless to say that without an autopilot, sprinting solo across the Atlantic would be impossible. But it took some ingenuity to devise a system suitable for a machine of this size. Meet Yoann le Quintrec, ‘Mr Pilot’ from Spindrift racing.
“The racing boats like those in the Vendée Globe or our future opponents in the Ultimate Class on the La Route du Rhum mostly use hydraulic pilots with actuators that operate the rudders,” Le Quintrec says. “That was an option that we had to discard because everything is supersized on board Spindrift 2 and there was no system that allowed us to have a strong enough lever arm. So, we had the idea of studying electrical pilots developed for large multihull cruisers. It was an idea that soon proved worthwhile.”