A surgical robot comprising a surgical robot arm and a surgical instrument. The surgical robot arm terminates at its distal end in a drive assembly comprising a first drive interface element. The surgical instrument comprises a shaft, an articulation attached to the distal end of the shaft, and a driving mechanism at the proximal end of the shaft. The articulation is for articulating an end effector, the articulation driveable by at least a first driving element and a second driving element. The driving mechanism comprises a first instrument interface element to which the first driving element is connected and a second instrument interface element to which the second driving element is connected. The first drive interface element engages both the first and second instrument interface elements such that: when the first drive interface element moves linearly, both the first and second instrument interface elements move in the same linear direction thereby driving both the first and second driving elements in the same direction and when the first drive interface element rotates, the first and second instrument interface elements move reciprocally in opposing linear directions thereby driving the first and second driving elements in opposing directions.Linvention concerne un robot chirurgical comprenant un bras de robot chirurgical et un instrument chirurgical. Le bras de robot chirurgical aboutit, à son extrémité distale, à un ensemble dentraînement comprenant un premier élément dinterface dentraînement. Linstrument chirurgical comprend un arbre, une articulation fixée à lextrémité distale de larbre, et un mécanisme dentraînement à lextrémité proximale de larbre. Larticulation sert à articuler un effecteur dextrémité. Elle peut être entraînée par au moins un premier élément dentraînement et un second élément dentraînement. Le mécanisme dentraînement comprend un premier élément dinterface dinstrument auquel le premier élément dentraînement est connecté, et un second élé
