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Arm and finger paralysis, e.g. due to brain stem stroke, often results in the inability to perform activities of daily living (ADLs) such as eating and drinking. Recently, it was shown that a hybrid electroencephalography/electrooculography (EEG/EOG) brain/neural hand exoskeleton can restore hand function to quadriplegics, but it was unknown whether such control paradigm can be also used for fluent, reliable and safe operation of a semi-autonomous whole-arm exoskeleton restoring ADLs. To test this, seven abled-bodied participants (seven right-handed males, mean age 30 ± 8 years) were instructed to use an EEG/EOG-controlled whole-arm exoskeleton attached to their right arm to perform a drinking task comprising multiple sub-tasks (reaching, grasping, drinking, moving back and releasing a cup). Fluent and reliable control was defined as average ‘time to initialize’ (TTI) execution of each sub-task below 3 s with successful initializations of at least 75% of sub-tasks within 5 s. During use of the system, no undesired side effects were reported. All participants were able to fluently and reliably control the vision-guided autonomous whole-arm exoskeleton (average TTI 2.12 ± 0.78 s across modalities with 75% successful initializations reached at 1.9 s for EOG and 4.1 s for EEG control) paving the way for restoring ADLs in severe arm and hand paralysis.

In this paper we validate a gravity compensation algorithm for a novel shoulder-elbow exoskeleton, aimed at compensating the device weight during the execution of rehabilitation exercises. Along with the description of the exoskeleton, we present the results of the validation of the algorithm on data acquired in static and dynamic trials, in unloaded conditions. Results showed good performance of the algorithm in calculating the gravity torque of each joint, suggesting the possibility to implement rehabilitation exercises in which a specific net amount of assistive torque is provided to the user’s joints.

In this paper preliminary results of the H2020 EUROBENCH project are reported. EUROBENCH aims at defining a unified benchmarking framework for bipedal robotics. In particular, in this paper the structure of the survey promoted by the EUROBENCH consortium and its initial results are briefly reported. Objective of the survey is addressing a comprehensive analysis of the priorities for bipedal walking robots from the stakeholders point of view (e.g. experts, end-users, etc.) both in the humanoids and in the wearable robotics fields.

Most recent findings in robot-assisted therapy suggest that the therapy is more successful if the patient actively participates to the movement (“assistance-as-needed”). In the present contribution, we propose a novel approach for designing highly flexible protocols based on this concept. This approach uses adaptive oscillators: a mathematical primitive having the capacity to learn the high-level features of a quasi-sinusoidal signal (amplitude, frequency, offset). Using a simple inverse model, we demonstrate that this method permits to synchronize with the torque produced by the user, such that the effort associated with the movement production is shared between the user and the assistance device, without specifying any arbitrary reference trajectory. Simulation results also establish the method relevance for helping patients with movement disorders. Since our method is specifically designed for rhythmic movements, the final target is the assistance/rehabilitation of locomotory tasks. As an initial proof of concept, this paper focuses on a simpler movement, i.e. rhythmic oscillations of the forearm about the elbow.

Low-back wearable robots are emerging tools to provide support to operators during handling of goods and repetitive operations. In this paper, we present and validate a novel control strategy for an active pelvis orthosis, which operates intuitively and effectively to assist workers during lifting operations. The proposed control strategy has a hierarchical architecture: the first layer (the intention-detection module) aims to detect online the onset of the lifting movement; the second layer (the assistive strategy) computes the reference torque profile to assist the movement, after the movement onset is detected; the third layer (the low-level control layer) aims at setting the current to drive the actuators. The control strategy relies on the angle measurements acquired by the encoders integrated in the robotic device and does not need additional sensors to detect the event. The system was tested on a pool of five healthy subjects, who were requested to perform repetitive lifting movements: first, the subject was requested to bend the trunk, grasp the box, lift it up and place it on a table; second, the subject was requested to grasp the object from the table, lower it down, place it on the floor and get up without the load. The tasks were executed with the exoskeleton controlled in transparent and assistive modes. Results show that the assistive action allows to perform the lifting movement faster. Significant reductions of the activity of the Lumbar Erector Spinae muscles were observed in the assistive mode compared to the transparent mode: a 16% reduction was observed when extending the trunk while holding the weight and a 33% reduction when extending the trunk without holding the load.

There is a growing need to assist those who have suffered an amputation due to vascular diseases, especially in those who have general lower limb weakness and need additional assistance to retain independence and overall quality of life. The CYBERLEGs system is a new artificial physical and cognitive lower-limb replacement system for dysvascular transfemoral amputees intended for assistance in activities of daily living. By lowering the cognitive and metabolic effort of using a prosthetic system, CYBERLEGs is intended to increase the number of amputees using prosthetic systems as well as expand the capabilities of those who use currently available technology.

Lumbar exoskeletons have the potential to reduce work-related musculoskeletal disorders and injuries in workers performing repetitive manual handling tasks. For a wide adoption of exoskeletons in industrial workplaces the definition of methodologies and metrics is crucial. In this paper, we present an overview of evaluation methods and metrics from state-of-the-art studies and propose a set of suitable evaluation tests and metrics to evaluate lumbar exoskeletons.

Active prostheses have recently come onto the market, but are limited to modular forms without connections between the knee and ankle modules. Here we present the simulation, design, and preliminary data of a new knee-ankle prosthesis with an actuated ankle based on a variable stiffness actuator with energy transfer from the knee to the ankle as a part of the CYBERLEGs FP7-ICT project. The CYBERLEGs a-Prosthesis utilizes a novel active ankle joint architecture and energy transfer mechanism to transfer energy from the knee joint to the ankle. The device is capable of producing a level ground walking gait that closely approximates the joint torques and kinematics of a non-amputee while while maintaining compliant joints, which has the potential to decrease impulse losses, and ultimately reduce the end user energy consumption. This first prototype consists of a passive knee and an active ankle, which are energetically coupled to reduce the total power consumption of the device.

Nowadays, lower-limb prostheses are reaching real-world usability especially on ground-level walking. However, some key tasks such as stair walking are still quite demanding. Providing haptic feedback about the foot placement on the steps might reduce the cognitive load of the task, compensating for increased dependency on vision and lessen the risk of falling. Experiments on intact subjects can be useful to define the feedback strategies prior to clinical trials, but effective methods to assess the efficacy of the strategies are few and usually rely on the emulation of the disability condition. The present study reports on the design and testing of a wearable haptic feedback system in a protocol involving intact subjects to assess candidate strategies to be adopted in clinical trials. The system integrated a sensorized insole wirelessly connected to a textile waist belt equipped with three vibrating motors. Three stimulation strategies for mapping the insole pressure data to vibrotactile feedback were implemented and compared in terms of intuitiveness and comfort perceived during level and stair walking. The strategies were ranked using a relative rating approach, which highlighted the differences between them and suggested guidelines for their improvement. The feedback evaluation procedure proposed could facilitate the selection and improvement of haptic feedback strategies prior to clinical testing.