Abstract: A magnetorheological (MR) actuator device comprising two or more MR actuator units. Each of the MR actuator units may include a motor, an MR fluid clutch apparatus operatively coupled to the motor to receive torque from the motor, the MR fluid clutch apparatus operable to generate a variable amount of torque transmission when subjected to a magnetic field. An output member is provided, a transmission operatively coupling the at least two MR actuator units to the output member, for the output member to receive torque from the MR actuator units. A controller for controlling the two or more MR actuator units to drive the output member, the controller driving the output member in at least an antagonistic mode in which the MR actuator units transmit torque in opposite directions to the output member. A collaborative mode may be provided to combined the torque of the two or more MR actuator units in a common direction on the output member.

Abstract: The invention relates to a device for positioning in the proximity of a joint between two portions, the device comprising a first interface (11) carried by a first of the two portions and a second interface (12) carried by a second of the two portions, the device including at least one connection between the first interface and the second interface, the connection comprising a double cylinder having two chambers that are connected together by a floating piston, the first of the two chambers being connected to the first interface and a second of the two chambers being connected to a drive rather of the double cylinder, said rod being connected to the second interface. The invention also relates to a system including such a device.

Abstract: A system comprises one or more wearable devices including a first body interface adapted to be secured to a first bodily part. A second body interface is adapted to be secured to a second bodily part separated from the first bodily part by a physiological joint. One or more joints provide one or more degrees of freedom between the first body interface and the second body interface. A magnetorheological (MR) fluid actuator unit comprises one or more power sources. An MR fluid clutch apparatus receiving torque from the at least one power source, the at least one MR fluid clutch apparatus operable to generate a variable amount of torque transmission when subjected to a magnetic field. A transmission couples the MR fluid actuator unit to the wearable device for converting torque from the MR fluid actuator unit to relative movement of the body interfaces with respect to one another.