Stroke patients are often affected by hand impairment. Literature shows different experiences of robotic rehabilitation that is able to prove an intensive and effective therapy. A preliminary analysis of the state of the art evidenced lacks in hand robotic rehabilitation devices. Thus, this work proposes a new rehabilitation device for hand rehabilitation based on a compliant transmission. The mechanical power generator is not on the hand to reduce the weight of the device. The mechanical model of the system is descripted. Experimental results on 126 stroke patients evidenced the efficacy of this device

This paper presents a proof of concept study on an innovative pneumatic mini-valve. The novelty aspects lie in the creation of an actuation device based on wires formed from the shape memory alloy (SMA) Ni-Ti and in the shape of the body of valve, with its very limited dimensions being made possible by its construction using mouldable polymeric materials. The proposed device has the following advantages: easy assembly, compactness, silent functioning, bio-compatibility, low power activation, and it is cheap to produce. Extensive static and dynamic characterizations of the value are performed using a dedicated test rig. Several different valves were measured to ensure measurement reproducibility. The static characteristics of the SMA-based valve are equivalent to those of commercially available valves. A 10 ms activation time and a 90 ms seating time are obtained at a 30 per cent duty cycle and a 1.5Hz frequency.

Exoskeleton robots are a rising technology in industrial contexts to assist humans in onerous applications. Mechanical and control design solutions are intensively investigated to achieve a high performance human-robot collaboration (e.g., transparency, ergonomics, safety, etc.). However, the most of the investigated solutions involve high-cost hardware, complex design solutions and standard actuation. Moreover, state-of-the-art empowering controllers do not allow for online assistance regulation and do not embed advanced safety rules. In the presented work, an industrial exoskeleton with high payload ratio for lifting and transportation of heavy parts is proposed. A low-cost mechanical design solution is described, exploiting compliant actuation at the shoulder joint to increase safety in human-robot cooperation. A hierarchic model-based controller with embedded safety rules is then proposed (including the modeling of the compliant actuator) to actively assist the human while executing the task. An inner optimal controller is proposed for trajectory tracking, while an outer safety-based fuzzy logic controller is proposed to online deform the task trajectory on the basis of the human’s intention of motion. A gain scheduler is also designed to calculate the inner optimal control gains on the basis of the performed trajectory. Simulations have been performed in order to validate the performance of the proposed device, showing promising results. The prototype is under realization.

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A new device for hand rehabilitation of stroke patient is presented. Its main innovative features are: lightness, real safety guaranteed by its structural elasticity, smoothness and easiness of movements. The kinematic behavior of the system hand-plus-rehabilitation-device is analyzed. The device applicability is confirmed by positive testing. Cerebrovascular diseases are the third cause of mortality and the second cause of long term disability in Western countries. The 60% of survived individuals shows a sensitive/motor deficit of one or both hands and must be subjected to a rehabilitative treatment to recover the use of the upper limb. Recent technologies have facilitated the use of robots as assistive tools to patients, providing safe and highly personalized rehabilitation sessions, thus making therapist contribution to recovery much more intensive and effective. We propose in this work a wearable glove with an incorporated compliant mechanical transmission over the hand. The glove is composed by two main modules with well-defined mechanical characteristics. One is the actuator on the upper side of the forearm, close to the wrist (and to the impaired hand) and still separated from it; the other (the transmission) is composed by several elastic transmissions which, moved by the actuator, properly transmit displacements, speed and forces to one or more impaired fingers during a rehabilitation session. While the actuator module has a rigid and defined structure and is fixed to the forearm section of the glove, the “transmission” module has in fact a labile and extended structure as it has to reach all five fingers (one, some, or all might be impaired and in need of rehabilitation) up to their tips and move them in an effective and reliable way. A kinematical characterization of the compliant transmission is proposed to dimension the actuators and to define the correct commanded motion profile at actuator level.