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Lower limb prosthetic device with active assistance functionality

Active assistanceCoupling devicelower limb prosthesisprosthetic device


The main priorities of use of lower limb prostheses, by the amputee, are related to comfort, lightness, reliability, low cost and propulsive assistance for the most demanding activities (lift, stairs, ramps). For such activities, however, the prostheses currently on the market offer few solutions and poorly appreciated due to high weight, difficulty of use and high cost. The aim of this invention is to create a small size and weight transfemoral patient prosthesis, while increasing user-friendliness. Inside the proposed prosthetic device, the actuator that allows to realize the active assistance functions is able to disengage depending on the patient’s activity. A passive mechanical graft is provided, which allows the joint to move freely in the angular range of physiological movement, transforming the prosthesis into assisted only when necessary.

Technical features

Prosthetic device, capable of replacing at least part of a user’s lower limb, comprising a proximal prosthetic portion capable of being coupled to a user limb segment and a distal prosthetic portion. The proximal prosthetic portion and the distal prosthetic portion are articulated by an articular portion comprising an actuator assembly to operate the distal portion in rotation with respect to this proximal portion around an axis of rotation. A damper assembly is provided connected to the said articular portion and able to absorb energy when a pair is applied between said proximal portion and said distal portion. The articulating actuator assembly is equipped with a removable mechanical coupling device such that the actuator assembly is switchable from a coupled condition in which it rotates the distal portion with respect to this proximal portion under a condition decoupled into to which the distal portion is coupled only to the said damper assembly for a predetermined angle of rotation. TRL 7.

Possible Applications

  • Prosthetic device, capable of replacing at least part of a user’s lower limb


  • Use of a mechanical coupling device that allows for decoupling between the actuator assembly and the damper assembly, as they are responsible for the operation of the prosthesis in different operational activities, allowing the user to perform assisted movements actively or passively dampened
  • Greater versatility for the activities that can be tackled compared to micro controlled passive prostheses
  • Reduced size and weight
  • Competitive production costs in view of future production on large ladder