Towards complex and continuous manipulation : a gesture based anthropomorphic robotic hand design

Most current anthropomorphicrobotic hands can realize part of the human hand functions, particularly for object grasping. However, due to the complexity of the human hand, few current designs target at daily object manipulations, even for simple actions like rotating a pen. To tackle this problem, we introduce a gesture based framework, which adopts the widely-used 33 grasping gestures of Feix as the bases for hand design and implementation of manipulation. In the proposed framework, we first measure the motion ranges of human fingers for each gesture, and based on the results, we propose a simple yet dexterous robotic hand design with 13 degrees of actuation. Furthermore, we adopt a frame interpolation based method, in which we consider the base gestures as the key frames to represent a manipulation task, and use the simple linear interpolation strategy to accomplish the manipulation. To demonstrate the effectiveness of our framework, we define a three-level benchmark, which includes not only 62 test gestures from previous research, but also multiple complex and continuous actions. Experimental results on this benchmark validate the dexterity of the proposed design and our video is available in https://drive.google.com/file/d/1wPtkd2P0zolYSBW7_3tVMUHrZEeXLXgD/view?usp=sharing.National Research Foundation (NRF)s. This work was supported by National Research Foundation, Singapore under its International Research Centres in Singapore Funding Initiative and Institute for Media Innovation, Nanyang Technological University (IMI-NTU)

Effect of time and body position on ventilation in premature infants

Background:Infants with respiratory dysfunction undergo regular position changes to improve lung function however it is not known how often a position change should occur. This study measured changes in lung function occurring over time after repositioning in preterm infants.Methods:Changes in end-expiratory level (EEL) and ventilation distribution were measured 30 mins, 2 h, and 4 h after repositioning into either prone, quarter turn from prone, or supine using Electrical Impedance Tomography (EIT). Physiological measurements were also taken.Results:Sixty preterm infants were included in the study. Infants receiving respiratory support (mechanical ventilation or continuous positive airway pressure (CPAP)) had improved ventilation homogeneity after 2 h (P < 0.01), maintained at 4 h. Spontaneously breathing infants had improved homogeneity at 2 h (P < 0.01) and improved global EEL after 4 h (P < 0.01) whereas infants receiving CPAP demonstrated an improved global EEL at 2 h (P < 0.01).Conclusion:Regional ventilation distribution is influenced by time independent of changes due to body position. Differences exist between infants on ventilatory support compared with those who are spontaneously breathing. Infants receiving ventilatory support have a physiological peak in lung function after 2 h which remains above baseline at 4 h. A change in body position facilitates an improvement in lung function in infants on ventilatory support