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Abstract-Human operation of continuum "continuousbackbone" manipulators remains difficult, because of both the complex kinematics of these manipulators and the need to coordinate their many degrees of freedom. We present a novel synergy-based approach for operator interfaces, by introducing a series of octopus-arm inspired grasp-synergies. These graspsynergies automatically coordinate the degrees of freedom of the continuum manipulator, allowing an operator to perform kinematically complex grasping motions through simple and intuitive joystick inputs. This effectively reduces the complexity of operation and allows the operator to devote more of his attention to higher-level concerns (e.g. goal, environment). We demonstrate the grasp-synergies interface design in both simulation and hardware using the nine degree of freedom Octarm continuum manipulator.

In vertebrates, facultative parthenogenesis (i.e. asexual reproduction by a sexually reproducing species) has been documented in four diverse taxonomic groups, namely sharks, birds, lizards, and snakes. With a single exception, the mode is terminal fusion automixis, where the second polar body fuses with the nucleus of the gamete, restoring diploidy and triggering cell division. The deviating case involves a report of a captive Burmese python (Python bivittatus), a giant Asiatic species common in zoological gardens and the pet trade. Although terminal fusion automixis produces half-clones of the mother, under this unique case in P. bivittatus, the foetuses were reported as full clones. This conclusion is an apparent anomaly with respect to the mechanism of facultative parthenogenesis reported in all other snakes. In the present study, using genotyping methods, we analyze facultative parthenogenesis in two other species of pythonids and report results that challenge the abovementioned conclusions regarding clonality. Specifically, we report new findings comparable to those reported in other primitive snakes (namely boids), which support the hypothesis of terminal fusion automixis as the mode of facultative parthenogenesis. Furthermore, in light of our new data, we re-examine the previous report of facultative parthenogenesis in the Burmese python and suggest an intriguing alternative explanation for the earlier findings.

This paper introduces new analyses and algorithms which are essential for the practical implementation of continuous backbone continuum robots. Actuator length limits strongly shape the configuration or joint space of continuum manipulators, introducing couplings which are not reflected in previously published kinematic models. These unmodeled effects significantly restrict the practical application of previously established kinematic models on continuum robot hardware. This paper presents a new analysis of the effects of actuator limits on continuum robots. Based on the new understanding of the configuration space uncovered, we derive for the first time the configuration space of continuum robots when constrained by actua-tor length limits. These contributions are essential for effective use of a wide range of continuum robots and have been implemented and tested on two different types of continuum robots. Results and insight gained from this implementation are presented .