A system for interfacing with an operator's body for a function unit, comprising: - a frame intended to be positioned on the rear side of the operator's torso, and defining a main extension direction which, in a worn condition of said system, is oriented parallelly to the longitudinal axis of the operator, - a plurality of contact units, which are connected to said frame and, in the worn condition of said system, are intended to be brought into contact with the operator's torso and hips, wherein said plurality comprises: - a first contact unit or a first series of contact units configured to position themselves on the front side of the operator's thoracic region; - a second contact unit or a second series of contact units configured to position themselves on the rear side of the operator's thoracic region; - a third contact unit or a third series of contact units configured to position themselves on the operator's hips; wherein each contact unit comprises a first and a second support (41, 42), and at least one elastic body, which is interposed between said first and second support (41, 42), and which is deformable so as to allow position and/or orientation variations between said first and second supports (41, 42), said first support being intended to be brought into contact with the operator's body in said worn condition of the interface system; - a plurality of flexible elements for connecting to said frame said first contact unit, or said first series of contact units. - a frame intended to be positioned on the rear side of the operator's torso, and defining a main extension direction which, in a worn condition of said system, is oriented parallelly to the longitudinal axis of the operator, - a plurality of contact units, which are connected to said frame and, in the worn condition of said system, are intended to be brought into contact with the operator's torso and hips, wherein said plurality comprises: - a first contact unit or a first series of contact units configured to position themselves on the front side of the operator's thoracic region; - a second contact unit or a second series of contact units configured to position themselves on the rear side of the operator's thoracic region; - a third contact unit or a third series of contact units configured to position themselves on the operator's hips; - a first contact unit or a first series of contact units configured to position themselves on the front side of the operator's thoracic region; - a second contact unit or a second series of contact units configured to position themselves on the rear side of the operator's thoracic region; - a third contact unit or a third series of contact units configured to position themselves on the operator's hips; wherein each contact unit comprises a first and a second support (41, 42), and at least one elastic body, which is interposed between said first and second support (41, 42), and which is deformable so as to allow position and/or orientation variations between said first and second supports (41, 42), said first support being intended to be brought into contact with the operator's body in said worn condition of the interface system; - a plurality of flexible elements for connecting to said frame said first contact unit, or said first series of contact units. - a plurality of flexible elements for connecting to said frame said first contact unit, or said first series of contact units.