Motorized assistance system comprising a tibial orthosis including:- A tibial fastening (1) that covers the user's shin.- An ankle fastening (2) articulated with a plantar fastening (3) at the axis of the ankle.- A processor (6)；The tibial fastening (1) can comprise a support (5) of a motorized winch (7), in which a strap (8) is hooked, whose free end is fixed to the foot, so that the winch (7) takes up the strap (8) when a foot position sensor indicates that it is not resting on the ground. Alternatively, the system can comprise a femur orthosis with two femur actuators (11, 12) that take up or release two strap in parallel, one attached to a harness or belt (13) and the other to the tibial fastening (1).The system may comprise additionally or alternatively a hip orthosis.
