Abstract: An active control method to control the vibrations of an articulated arm consisting of a plurality of segments articulated with respect to each other, by means of an electronic controller, comprising the following steps: a) construction of a modal model of the articulated arm starting from experimental data or from structural models; b) assignation of gains of electronic controller; c) multiplication of gains by the difference between the reference modal coordinates and those calculated through the modal model starting from directly measured quantities, in order to determine the control forces to be applied to the arm, or to at least part of the relative segments; d) evaluation of the modal coordinates by means of a states estimator; e) comparison between measurements estimated using the modal coordinates and real measurements and correction of the estimate, so that the estimate converges on real values.

Abstract: An arm to distribute concrete comprising a plurality of articulated segments selectively able to be folded back and extended with respect to each other, made of composite material, wherein at least one of said segments comprises at least a first tract and a second tract, each having a constant cross section, wherein the section size of the first tract is different from the section size of the second tract, a connection tract being provided between said first tract and said second tract.

Abstract: The device to actively control the vibrations of an articulated arm consisting of a plurality of segments each comprising at least its own actuator associated with a hydraulic drive circuit including a block valve. At least one of said actuators is associated with an auxiliary control circuit of the vibrations, comprising at least a sensor able to detect the vibrations and/or the position of one or more segments, a processing unit to process the signals of the sensor/sensors and a pump commanded by the processing unit and cooperating with said block valve. The auxiliary control circuit is associated with the hydraulic drive circuit.

Abstract: An arm made of composite material, and relative production method, consisting of a plurality of articulated segments with a longitudinal main axis (x), pivoted to each other, each of the articulated segments comprising a box-like structure and at least a joint element attached thereto by means of gluing, the box-like structure having an end cooperating with an end of the joint element on the inside of the surface of the joint element. The ends define a substantially conical reciprocally overlapping area and have profiles concordantly inclined by an angle (?) with respect to the longitudinal axis (x).

Abstract: A method to make an arm for the distribution of concrete, or other material similar to concrete, used on heavy work vehicles, wherein the arm comprises a plurality of segments selectively folding and extendible one with respect to the other. Each segment comprises a main girder and auxiliary elements for connection to adjacent segments or for attachment of movement and/or supporting devices for the pipe that carries the concrete. The method comprises a first step in which each main girder is formed, with a predefined length, by depositing a plurality of layers of pre-impregnated composite material in a female type mold. The method comprises a second step in which the composite material, deposited in layers in the mold in a variable number of layers, is subjected to polymerization. The method comprises a third step in which each main girder is removed from the mold and a fourth step in which the auxiliary elements are associated with each girder so as to form a relative segment.

Abstract: An active control method to control the vibrations of an articulated arm consisting of a plurality of segments articulated with respect to each other, by means of an electronic controller, comprising the following steps: a) construction of a modal model of the articulated arm starting from experimental data or from structural models; b) assignation of gains of electronic controller; c) multiplication of gains by the difference between the reference modal coordinates and those calculated through the modal model starting from directly measured quantities, in order to determine the control forces to be applied to the arm, or to at least part of the relative segments; d) evaluation of the modal coordinates by means of a states estimator; e) comparison between measurements estimated using the modal coordinates and real measurements and correction of the estimate, so that the estimate converges on real values.