Abstract: The invention concerns an apparatus comprising an arm (4) which, mounted on a support at one of its ends, comprises several elements (5, 6, 7) articulated on one another about horizontal pins (8, 9) and equipped, at its other end, with a tool-holder (15). At its free end, the arm is equipped with a rotary actuator (12) with rotation pin (12) transverse to the hinge pins (8, 9) of the elements (5, 6, 7) of the arm, and on the lower part of which is fixed a housing (15) containing a motor (16) designed to drive an output shaft (23) transverse to the rotary actuator axis and at the tip of which is mounted cantilevered a tool (33, 34). The invention is applicable to tillage on steep grounds or with marked irregular features, such as trenches.

Abstract: The invention concerns a method for automatically moving on the ground a tool mounted at the end of an articulated arm. It consists in bringing the tool (7, 17, 27) onto a first point of the surface and in calculating the co-ordinates of said point; in bringing the tool onto a second point enabling to set a first axis of co-ordinates of the working plan and to determine the furthermost point to be reached on said axis; in bringing the tool onto a third point close to the second co-ordinate axis and enabling to define the position of the frame of reference of the working plan, then in a fourth point delimiting the zone plane inside which the work will be performed and in defining a working plan for the tool capable of being superimposed with the working surface so as to enable it to cover, by discontinuous or continuous movements, the entire working surface.

Abstract: The invention concerns a device mounted on a carrier vehicle equipped with at least a support (4) whereon a frame (6) is mounted in articulation, with interposed a pressure actuator (8), the frame being equipped at its bottom end with a plurality of vertical bars (24) whereof the lower ends (26) are provided with feet (28) and whereof the upper ends are provided each with a piston (15) mounted sliding into a cylinder (13). A mechanical component (10) called a proportioning unit, wherein are arranged the cylinders (13) used for fixing the pistons (15) disposed at the upper ends of the bars (24), and comprising a chamber (14) communicating said cylinders, is mounted sliding between stop elements (12, 13) in the frame, parallel to the axes of the cylinders (13), the mechanical component forming a proportioning unit (10) is directly subjected to the action of the thrust forces of the actuator (8) via the frame stops (12).