The main goal of the proposed work comprises the development of a powered knee orthosis ("PKO") system, embedded with wearable gait sensors (inertial measurement unit - IMU, electromyography - EMG, and force sensitive resistors - FSRs), capable of assisting subjects with gait disorders and monitor human gait pattern. The orthotic device is a knee H2-Joints, a powered modular joint from the lower limb exoskeleton H2 (Technaid, Madrid, Spain). The overall validation of the rehabilitation tool will be carried out with the development of novel control strategies for knee motion assistance, suitable for distinct types of therapies. Moreover, it also includes the design and validation of a gait segmentation algorithm. These strategies can be in tegrated in a hierachical control architecture (low-, mid-, and high-level controllers), inspired in the fucntioning of the human motor control (bioinspired).

    Furthermore, this master thesis also aims to present the design, technical description, and preliminary implementation, of a modular, bioinspired, real-time, power- and time-effective, and ergonomic architecture for wearable orthoses (ankle and knee H2-Joints), called "SmartOS", which acts and cooperates closely with the human being. Regarding the integration of motion assistive strategies, this architecture will follow the same hierarchical principals designed for PKO. Moreover, the system should be configurable by users and capable of monitoring gait therapies in real-time.

     To accomplish the main objective outlined, the following goals shall be achieved:         

-       Goal 1: Familiarization with concepts of human gait and technologies of ambulatory exoskeletons and active orthoses systems.

-       Goal 2: Conceptual design, technical and functional description and preliminary validation of PKO system, embedded with external wearable gait sensors.   

-       Goal 3: Design and validation with healthy subjects of a real-time gait pattern segmentation method, suitable for distinct walking conditions (speeds and slopes), based on one gyroscope mounted in instep of the foot. This tool must detect with accuracy and time-effectiveness the two gait phases and several gait events during walking.

-       Goal 4: Hierarchical design and validation with healthy subjects of motion assistive strategies for PKO, namely tracking control (position- and torque-based low-level control), and assist-as-needed strategies (impedance control and myoelectric control).

-       Goal 5: Design, technical description and preliminary results of SmartOs system. This goal comprises a high-level definition of the main functional blocks, in terms of components, functionalities, hardware interfaces, software structures, processing units, and operating systems, and culminates with the design and preliminary implementation of a new smart hierarchical control architecture for powered orthotic devices, aiming the integration of more than one actuation system, namely, a knee and ankle H2 joints.