A herringbone soft pneu-net actuator for enhanced conformal gripping

Advances in material science in recent years have had such a tremendous impact on the field of soft robotics that has fostered the development of many bio-inspired devices. One such device, which has been subject to extensive study in recent times, is soft pneumatic-network (pneu-net) actuators (SPAs). In this study, we present a new SPA structure whose chamber configuration mimics the fish bone (herringbone) structure to facilitate simultaneous bending deformations in both longitudinal and transverse directions. Such as cannot be obtained from the regular pneu-net structure – which bends only lengthwise, the coupled bending curvatures allow for gripping with maximized contact area, a property which facilitates firmness, security, and stability in gripping. Using the corresponding chamber inclination angle of the configuration as key parameter, the combined transverse and longitudinal deformation feature is studied through finite element simulation as well as experiments. Also, the functional behavior of the actuator/gripper prototypes is experimentally investigated using a series of approaches including blocked (or tip) force test, grip strength test, and stability (or sustained grasping force) test. Furthermore, the viability of the said conformal gripping characteristic is demonstrated by subjecting the structure to a couple of gripping tests. This utility-enhancing design approach could really guide into the development of more sophisticated application-custom soft robotic capabilities.

Functional outcomes of post-traumatic metacarpal hand reconstruction with free toe-to-hand transfer

ABSTRACT Introduction: We present the functional outcomes of microvascular toe transfer to reconstruct the post-traumatic metacarpal hand deformity. Twelve toe transfers were successfully carried out in 11 patients. Materials and Methods: In each patient, the level of injury was classified according to the Wei classification system. Functional outcome was measured in seven patients using the Tamai score. Additional objective tests of function were carried out in three patients, including the Jebsen test, grip strength, pinch strength, web opening, static and moving two-point discrimination and Semmes–Weinstein monofilament testing. Observation and Results: The average Tamai score was 69 (range 60–83.5). Six patients achieved 'good' outcomes and one patient, with a double toe transfer, an 'excellent' outcome. The average follow-up time was 43 months (range 10–148 months). Conclusion: This study shows how even a single toe transfer can restore useful function to a hand that has otherwise lost all prehensile ability.

Synthesis and Neuropharmacological Evaluation of Some Novel Quinoxaline 2, 3-Dione Derivatives

Quinoxaline-2, 3-dione obtained from cyclocondensation reaction of o-phenylene diamine with oxalic acid was reacted with three different ketones and formaldehyde to give the corresponding Mannich bases in satisfactory yield. Their structures were confirmed by using1H NMR, IR, and mass analysis. In pharmacological evaluation, the synthesized compounds showed its curative effect against ethidium-bromide-induced demyelination in rats. For the purpose, different screening methods such as open field exploratory behavior test, rota rod test, grip strength test, beam walk test, and photo actometer test were performed. Ethidium bromide induction showed muscle weakness; muscle discoordination; loss of locomotor activity, and so forth, the synthesized drugs reversed all the above-mentioned neuromuscular disorders caused by ethidium bromide administration.