A locking device for locking an object capable of sliding along a cable, the device includes the cable and a clamp, the cable passing through the clamp while extending along an axis, the clamp comprising: a fixed part connected to the object, a ring comprising an elastic material with fluid behavior, the ring comprising a central cavity through which the cable passes, an actuator configured to compress the ring between two shapes, in a first shape, referred to as the open shape, the cable being able to run freely in the central cavity and in a second shape, referred to as the closed shape, the cable being compressed by the ring.