4,332 research outputs found
Design and analysis of a wire-driven flexible manipulator for bronchoscopic interventions
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
“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
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 . 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
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
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
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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