Abstract: A device for controlled translational displacement of an elongated element that terminates in a frontal functional end, in particular an instrument or a tool that is designed to be brought to an internal site in a patient, more particularly an exploratory instrument or a surgical tool placed in a catheter or in an operating channel or working channel of a flexible endoscope, whereby the device includes a linear actuator that acts at the rear end of the elongated element that is located opposite its frontal functional end. Device (1) that is characterized in that the actuator (5) consists of a direct-drive electromagnetic linear motor that includes a shaft (6) that moves in translation relative to a stator and that drives the elongated element (2), whereby the shaft (6) optionally can also be coupled to a rotary motor.