RESUMO
Stroke survivors can be affected by motor deficits in the hand. Robotic equipment associated with brain-machine interfaces (BMI) may aid the motor rehabilitation of these patients. BMIs involving orthotic control by motor imagery practices have been successful in restoring stroke patients' movements. However, there is still little acceptance of the robotic devices available, either by patients and clinicians, mainly because of the high costs involved. Motivated by this context, this work aims to design and construct the Hand Exoskeleton for Rehabilitation Objectives (HERO) to recover extension and flexion movements of the fingers. A three-dimensional (3D) printing technique in association with textiles was used to produce a lightweight and wearable device. 3D-printed actuators have also been designed to reduce equipment costs. The actuator transforms the torque of DC motors into linear force transmitted by Bowden cables to move the fingers passively. The exoskeleton was controlled by neuroelectric signal-electroencephalography (EEG). Concept tests were performed to evaluate control performance. A healthy volunteer was submitted to a training session with the exoskeleton, according to the Graz-BCI protocol. Ergonomy was evaluated with a two-dimensional (2D) tracking software and correlation analysis. HERO can be compared to ordinary clothing. The weight over the hand was around 102 g. The participant was able to control the exoskeleton with a classification accuracy of 91.5%. HERO project resulted in a lightweight, simple, portable, ergonomic, and low-cost device. Its use is not restricted to a clinical setting. Thus, users will be able to execute motor training with the HERO at hospitals, rehabilitation clinics, and at home, increasing the rehabilitation intervention time. This may support motor rehabilitation and improve stroke survivors life quality.
RESUMO
Patients with chronic obstructive pulmonary disease (COPD) may suffer dyspnea when performing unsupported arm exercises (UAE). However, some factors related to the tolerance of the upper limbs during these exercises are not well understood. Our investigation was to determine if an unsupported arm exercise test in patients with COPD accomplishing diagonal movements increases lactic acid levels; also, we assessed the metabolic, ventilatory and cardiovascular responses obtained from the unsupported arm exercise test. The study used results of maximal symptom limited tests with unsupported arms and legs performed on 16 patients with COPD. In order to do the test, some metabolic, respiratory and cardiovascular parameters such as oxygen uptake (VO(2)), carbon dioxide production (VCO(2)), respiratory rate (RR), pulmonary ventilation (VE), heart rate (HR) and blood pressure (BP) were measured during the exercise tests. Furthermore, blood lactate concentration was measured during the arm test. We detected a significant increase in the mean blood lactate concentration, VO(2), VCO(2), VE and RR from the resting to the peak phase of the UAE test. The mean values of VO(2), VCO(2) and VE obtained at the peak of the UAE test corresponded to 52.5%, 50.0% and 61.2%, respectively, of the maximal values obtained at the peak of the leg exercise test. In comparison, the mean heart rate and systolic arterial blood pressure were significantly lower at the peak of the UAE test than at the peak leg exercise test and corresponded to 76.2% and 83.0%, respectively. Unsupported incremental arm exercises in patients with COPD increases blood lactic acid levels.