This paper presents a novel sensing information forecasting algorithm based on time series analysis for the power assist walking legs (PAWL). The goal of this algorithm is to improve the dynamic response of the exoskeleton. The algorithm is built up with the autoregressive (AR) model, the recursive least square (RLS) method and the final prediction error (FPE) criterion. The method of RLS is utilized to make the on-line parameters estimation, and the FPE criterion is used to select the order of AR model. The forecasting algorithm is designed to be used on-line and to make predictions of force sensing information to ensure the real-time quality of the whole system. The algorithm can be categorized into two types: one step forecasting method and multi-step forecasting method. Meanwhile, we make some simulations to verify the validity of this algorithm. At the end of this paper, the correlative experiments have been carried out, and the results demonstrate this sensing information forecasting algorithm can predict the value and the trend of the sensing signal precisely and effectively.

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The paper briefly describes the semi-anthropomorphic telemanipulation system and discusses the advanced capabilities that were demonstrated in the initial performance evaluation. The system’s terminus devices are anthropomorphic: an exoskeleton sixteen degree of freedom (DOF) glove controller that senses human finger forces and backdrives slave motions to every joint of its four instrumented fingers; and a four fingered sixteen DOF anthropomorphic slave hand-wrist-forearm. The master glove is attached to a non-anthropomorphic six DOF universal force-reflecting hand controller (FRHC). The mechanical forearm is mounted to an industrial robot (PUMA 560), replacing its standard forearm. Active electromechanical compliance (AEC) systems for each finger and the wrist provide adjustable compliance, enabling human-like soft grasping. The system is controlled by a high performance distributed control system. Initial performance evaluations focused on tool handling capabilities and astronaut equivalent task executions. Results reveal that the combination of a fingered hand and active compliance enables unprecedented task executions. But it also became evident that complex manipulations require a dual arm robot

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In this paper, a wearable robot gives assistance or support to human locomotion is proposed, it will be of great value for certain activities or for special groups. As the wearable exoskeleton moves according to human intention, how to acquire human locomotion information accurately and quickly become so significantly. Firstly, we make a dynamic analysis of walking human body and build a correlative dynamic model, then introduces our wearable robot which depends on human-robot interaction force to capture human motion information real-time. Its design is strictly in accordance with dynamic model. We also make a detailed introduction of the acquisition method for mechanical information from lower limbs, detection device and its principle of operation, a LAN(Local Area Network) based on CAN(Controller Area Network) bus used to acquire motion information of human lower limbs is constructed. At last, a series of experiments are carried out, by analysis of experimental data, we can clearly recognize and depict a whole process of human motion, this acquisition method is verified feasible and effective.

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For haptic devices, compensation of the robot’s gravity is a frequent strategy with the aim to reduce interaction forces between robot and human in zero-impedance control. However, a closer look at the composition of these interaction forces may reveal that the net effect of uncompensated gravitational components of the robot actually reduces interaction forces during dynamic movements, because inertial and gravitational components at least partially compensate each other. This is the case in lower extremity exoskeletons, where less user force is necessary to swing the robot’s leg when gravity helps. Here, we go one step further by shaping optimal passive dynamics for arbitrary haptic devices. The proposed method of generalized elasticities uses conservative force fields to improve haptic transparency for certain movements types. In an example realization, these force fields are generated by elasticities spanning multiple joints. Practical experiments with the Lokomat lower extremity exoskeleton show the success of the proposed method in terms of reduced interaction torques and more physiological user motion compared to gravity compensation.

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This work presents a novel wearable exoskeleton capable of moving the human wrist for rehabilitation or assistive purposes. The purpose of the device is to grant autonomy to individuals suffering from medical conditions such as frailty, spinal cord injury (SCI), stroke or other motor diseases. The device can be operated in two modes. The rehabilitation mode of the device moves the hand in a predefined manner and records the electromyography (EMG) signals for analysis. The assistive mode uses EMG signals to identify the intention of the user and the helps in the movement of the hand by supplying the assistive force. Principal Component Analysis (PCA) along with artificial neural networks is employed for EMG pattern recognition. Different aspects to this are currently under study and the initial design and test results for the device are discussed.

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