| 摘要 |
<p>An apparatus for cutting grass, comprising: a lawn mower provided with actuating means for movement of the lawn mower, one or more blades for grass cutting in a cutting area (S); an electric cable confining said cutting area; a management device associated with the cable and configured for outputting an electric signal comprising a plurality of pulses separated from each other, each pulse being formed with a portion of a substantially periodic carrier signal at a main frequency, which is phase-modulated with phase displacements equal to 0° or 180°. The management device is connected to the cable to make said electric signal propagate in said cable. The lawn mower is further provided with: sensor means for detecting the electric signal; an operating module configured for filtering in the electric signal, at least one first pulse in a main frequency band defining a neighbourhood of the main frequency, thus obtaining a corresponding first filtered pulse and identifying data D1 in the first filtered pulse as a function of the phase displacements; a memory in which main reference data (Ref) are contained; a main comparison module for comparing the data identified in the first filtered pulse and said main reference data, and generating a corresponding notification signal representative of the fact that said lawn mower is positioned inside or outside the cutting area; a connected control unit for operating the actuating means as a function of the notification signal.</p> |
