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BA111OD Chptr_Δ.6
CHPTR_Δ is the first BA111OD manufacture watch complication: a unique timepiece that represents time in a revolutionary way.
Rather than simply rotating a hand around a central axis, the movement was designed to "roll" a satellite hour wheel around a fixed central hour wheel. When a wheel is rotated around another wheel, the trajectory described by any point on this satellite wheel is a cycloid. There are several types of cycloids: in this BA111OD chapter, the chosen cycloid is a deltoid (with a ratio of 1/3), and as a result, the trajectory described by the tip of the hour hand is… a triangle.
Created with the help of renowned watchmaker Olivier Mory, CHPTR_Δ's asymm