4,332 research outputs found

    Design and analysis of a wire-driven flexible manipulator for bronchoscopic interventions

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    Bronchoscopic interventions are widely performed for the diagnosis and treatment of lung diseases. However, for most endobronchial devices, the lack of a bendable tip restricts their access ability to get into distal bronchi with complex bifurcations. This paper presents the design of a new wire-driven continuum manipulator to help guide these devices. The proposed manipulator is built by assembling miniaturized blocks that are featured with interlocking circular joints. It has the capability of maintaining its integrity when the lengths of actuation wires change due to the shaft flex. It allows the existence of a relatively large central cavity to pass through other instruments and enables two rotational degrees of freedom. All these features make it suitable for procedures where tubular anatomies are involved and the flexible shafts have to be considerably bent in usage, just like bronchoscopic interventions. A kinematic model is built to estimate the relationship between the translations of actuation wires and the manipulator tip position. A scale-up model is produced for evaluation experiments and the results validate the performance of the proposed mechanism

    A hyper-redundant manipulator

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    “Hyper-redundant” manipulators have a very large number of actuatable degrees of freedom. The benefits of hyper-redundant robots include the ability to avoid obstacles, increased robustness with respect to mechanical failure, and the ability to perform new forms of robot locomotion and grasping. The authors examine hyper-redundant manipulator design criteria and the physical implementation of one particular design: a variable geometry truss

    An Open-Source 7-Axis, Robotic Platform to Enable Dexterous Procedures within CT Scanners

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    This paper describes the design, manufacture, and performance of a highly dexterous, low-profile, 7 Degree-of-Freedom (DOF) robotic arm for CT-guided percutaneous needle biopsy. Direct CT guidance allows physicians to localize tumours quickly; however, needle insertion is still performed by hand. This system is mounted to a fully active gantry superior to the patient's head and teleoperated by a radiologist. Unlike other similar robots, this robot's fully serial-link approach uses a unique combination of belt and cable drives for high-transparency and minimal-backlash, allowing for an expansive working area and numerous approach angles to targets all while maintaining a small in-bore cross-section of less than 16cm216cm^2. Simulations verified the system's expansive collision free work-space and ability to hit targets across the entire chest, as required for lung cancer biopsy. Targeting error is on average <1mm<1mm on a teleoperated accuracy task, illustrating the system's sufficient accuracy to perform biopsy procedures. The system is designed for lung biopsies due to the large working volume that is required for reaching peripheral lung lesions, though, with its large working volume and small in-bore cross-sectional area, the robotic system is effectively a general-purpose CT-compatible manipulation device for percutaneous procedures. Finally, with the considerable development time undertaken in designing a precise and flexible-use system and with the desire to reduce the burden of other researchers in developing algorithms for image-guided surgery, this system provides open-access, and to the best of our knowledge, is the first open-hardware image-guided biopsy robot of its kind.Comment: 8 pages, 9 figures, final submission to IROS 201

    The kinematics of hyper-redundant robot locomotion

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    This paper considers the kinematics of hyper-redundant (or “serpentine”) robot locomotion over uneven solid terrain, and presents algorithms to implement a variety of “gaits”. The analysis and algorithms are based on a continuous backbone curve model which captures the robot's macroscopic geometry. Two classes of gaits, based on stationary waves and traveling waves of mechanism deformation, are introduced for hyper-redundant robots of both constant and variable length. We also illustrate how the locomotion algorithms can be used to plan the manipulation of objects which are grasped in a tentacle-like manner. Several of these gaits and the manipulation algorithm have been implemented on a 30 degree-of-freedom hyper-redundant robot. Experimental results are presented to demonstrate and validate these concepts and our modeling assumptions

    Perkaitan di antara status sosioekonomi keluarga dengan Pencapaian akademik pelajar aliran teknikal

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    Selain daripada mengendalikan fungsi pendidikan, sekolah juga diberikan peranan bagi menyediakan tenaga mahir untuk memenuhi keperluan ekonomi negara. Sekolah aliran teknikal dilihat sebagai satu institusi khusus yang memainkan peranan tersebut. Namun begitu, terdapat pelbagai faktor yang boleh mempengaruhi pencapaian pelajar aliran teknikal ini. Tahap sosioekonomi keluarga telah dikenalpasti antara faktor yang boleh mempengaruhi pencapaian pelajar. Kajian ini dilakukan untuk mendapatkan perkaitan di antara tahap sosioekonomi keluarga seperti tahap pendidikan bapa, jumlah pendapatan dan saiz keluarga terhadap pencapaian akademik pelajar. Sampel kajian ini ialah pelajar-pelajar tingkatan 4 dan 5 yang menetap di asrama Sekolah Menengah Teknik Kuala Terengganu. Pelajar ini dipilih kerana mereka mendapat kemudahan dan persekitaran pembelajaran yang sama. Seramai 80 orang pelajar dalam jurusan teknikal dipilih secara rawak mudah. Keputusan kajian mendapati bahawa hanya saiz keluarga mempunyai korelasi yang tinggi berbanding tahap pencapaian akademik bapa dan jumlah pendapatan keluarga. Ini menunjukkan bahawa faktor saiz keluarga memberikan impak secara langsung kepada pencapaian pelajar walaupun mereka menetap di asrama yang menyediakan suasana dan kemudahan yang sama
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