When the idea first came up of a turtle automaton with a singing bird on its back, Reuge – which had expanded from music boxes to also offering singing birds and who had developed MB&F’s MusicMachines – was the natural partnership choice. In turn, Reuge partnered with automaton specialist Nicolas Court to develop the mechanism that moves the turtle so realistically.
Kelys & Chirp is a joyous celebration of friends. Kelys (from the Greek chelone or chelys for tortoise) moves in a realistic tortoise-like gait with his head moving slowly side-to-side, his movements all in synchronicity with Chirp as springing from her nest and pirouetting, her beak opening and closing, wings flapping, and tail wagging, all in time to the melodic bird song.
The movement of Kelys & Chirp is actually in two parts: the Singing Bird, which is a complete movement itself, and the turtle automaton module, which is powered by the Singing Bird movement. Nicolas Court and his team developed the automaton mechanism around the Singing Bird movement and unsurprisingly faced significant challenges. These included how to move the relatively heavy (1.4 kg) turtle with only little power available from the small mainspring of the Singing Bird movement, while ensuring that the turtle moved with a realistic non-regular gait. The first was solved by finding the optimal low ratio gearing, the latter by the use of elliptical gearing in the power train.
Rather than move their paired legs alternatively like most animals, tortoises push themselves forward with both rear legs, after which the front legs catch up. This creates a very distinct intermittent start/stop gait that the Nicolas Court team eventually replicated by using elliptical gearing and cams, the shapes of the cams dictating the movement of the legs.
The turtle’s movements are synchronised with the bird’s own movements and singing. A friction clutch security system integrated into the automaton mechanism detects surface edges and immediately stops the turtle moving forward over the abyss.
Court also reintroduced a Reuge security system for the bird movement: if the bird is pushed down while singing (something to generally avoid), a lever system safely pivots the bird and it returns to nest.
Chirp’s birdsong sounds amazing, both due to the accuracy of the song and for the fact that such a relatively loud sound emits from such a small object. This is thanks to a 230-year-old invention, generally credited to Pierre Jaquet-Droz (1721–1790), who came up with the idea of the modern Singing Bird complication. By 1785, Droz had both miniaturized the mechanically-controlled bird and developed a compact movement: his secret was in recreating a realistic birdsong using just one bellow of variable pitch rather than multiple single-pitch bellows.
The scales on Kelys’ shell are individually hand made from high quality leather in 4 different colours, creating a warmer and more natural feel than bare metal.
Kelys & Chirp is available in 4 limited editions of 18 pieces each in blue, green, yellow or ochre.
