An autonomous intracorporeal capsule, including a body and, inside this body, electronic circuits and energy harvesting means for the power supply of these electronic circuits, the energy harvesting means comprising: - an actuation element, comprising a mobile surface of the body of the capsule adapted to subjected to the cyclic variations of pressure in the environment surrounding the capsule and to produce a cyclic mechanical stress under the effect of these variations of pressure; - a mechano-electric transducer comprising at least one deformable piezoelectric component; - a link element, coupling the actuation element and the piezoelectric component so as to transmit the mechanical stress to the piezoelectric component, at one point of application and following a direction of application, and to hence produce cyclically bending deformations of the piezoelectric component liable to generate electric charges, the piezoelectric component including a rectilinear, elongated flexible plate extending in a main plate direction (Δ), perpendicular to the direction of application of the mechanical stress; and - means for harvesting the so-produced electric charges, characterized in that: - the plate is configured as a free-embedded beam adapted to be stressed so as to bent with no inversion of curvature, with an embedded end integral with the capsule body and an opposite, free end, connected to the link element at the point of application of the mechanical stress; and - means for coupling the free end of the plate to the link element are further provided, these coupling means having a pivoting degree of freedom (α) between the main plate direction (Δ) and the direction of application of the mechanical stress. - an actuation element, comprising a mobile surface of the body of the capsule adapted to subjected to the cyclic variations of pressure in the environment surrounding the capsule and to produce a cyclic mechanical stress under the effect of these variations of pressure; - a mechano-electric transducer comprising at least one deformable piezoelectric component; - a link element, coupling the actuation element and the piezoelectric component so as to transmit the mechanical stress to the piezoelectric component, at one point of application and following a direction of application, and to hence produce cyclically bending deformations of the piezoelectric component liable to generate electric charges, the piezoelectric component including a rectilinear, elongated flexible plate extending in a main plate direction (Δ), perpendicular to the direction of application of the mechanical stress; and - means for harvesting the so-produced electric charges, - the plate is configured as a free-embedded beam adapted to be stressed so as to bent with no inversion of curvature, with an embedded end integral with the capsule body and an opposite, free end, connected to the link element at the point of application of the mechanical stress; and - means for coupling the free end of the plate to the link element are further provided, these coupling means having a pivoting degree of freedom (α) between the main plate direction (Δ) and the direction of application of the mechanical stress.