The invention relates to an active orthosis system comprising a plurality of inertial sensors to be distributed over an upper limb, a lower limb, or any other part of the human body comprising at least one joint, said inertial sensors (1, 2, 3, 4) being designed so as to allow the determination of at least one angle formed by segments of said part of the human body, around said at least one joint. The invention is characterised in that said active orthosis system comprises an alert device for warning the user of the active orthosis system that said at least one angle has a value located outside a pre-determined range of comfort values.
