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The goal of this work was to develop a virtual reality simulator for minimal invasive micro robotic neurosurgery, focusing on the case of transsphenoidal approach pituitary gland tumor resection. Particularly we work on the force feedback, collision avoidance and dynamic motion scaling. The main challenges in our work were the real time collision detection and the deformation of the soft tissues.
The da Vinci surgical system is now widely adopted in hospitals and research centers worldwide, with more than half a million clinical cases [1]. However, minimally invasive microsurgical procedures such as the transsphenoidal pituitary tumor resection has yet to be contemplated with robotic aid. Such necessity inspired some groups to use the da Vinci system in head and neck surgery, but with limited...
The use of robots in surgery is of great research interest following the widespread adoption of da Vinci systems in surgical rooms worldwide. Research interest has grown, as such robot aid still cannot fully perform procedures requiring smaller instruments and more precise movements. In addition to added flexibility, serial-link manipulators can also provide these capabilities for surgical procedures...
Endovascular coiling, if possible, is the preferred surgical treatment for cerebral aneurysms as it is minimal invasive. The use of endovascular coiling is limited by the accessibility to the cerebrovascular system by catheter. This study investigated the feasibility of a single electromagnetic coil pair system to control a microrobot in vascular phantoms to eventually increase the potential treatment...
Field survey for the 2003 Tokachi-oki earthquake tsunami was conducted by the scientists from all over Japan [Tanioka et al., 2004a, b]. Large tsunami heights of about 4 m were observed at Hyakuninhama to the east of Cape Erimo and along the beach between Horokayanto and Oikamanai. Those places are close to the source region of the earthquake. In general, tsunami heights gradually decreased to the...
This paper proposes the magnetic field analysis method of an induction motor using Three-Dimensional Axi-symmetric Finite Element Method (3D-ASFEM). The part of analysis that cannot be dealt with the two-dimensional magnetic field analysis is made by 3D-ASFEM. The induced voltage of the end ring is calculated by using the vector potentials obtained from 3D-ASFEM. Then, the circuit equations considering...
Partial Discharge (PD) measurement is well known as powerful method to identify the condition of high-voltage insulation. This paper investigates the properties of the ultra-high frequency (UHF) electromagnetic (EM) wave emanating from the air discharge (corona) under high voltage DC source. By applying both positive and negative high voltage DC ranging up to 135 kV, a rod antenna and a horn antenna...
In this work we present a data-driven approach to the rational design of battery materials based on both resource and performance considerations. This work builds upon previous efforts by Gaultois and coworkers to use data mining to explore battery materials. A large database of Li-ion battery material has been created by abstracting information from over 200 publications. The database consists of...
The field of medical microrobotics is rapidly progressing; however, it is particularly challenging to control microrobots inside blood vessels. In this paper, the magnetic propulsion of a microrobot in pulsating flow is investigated. Regarding this task, the advantages of a reduced blood flow velocity are examined. The required magnetic field gradient in relation to the size of the microrobot is theoretically...
We investigated the relationship between workspace reduction due to collisions and the distance between the endoscope and target organ to develop a new algorithm for endoscope navigation in pediatric endoscopic surgery. Proper endoscope position is important for pediatric endoscopic surgery: the endoscope needs to get close to the target organ to obtain a suitable field of view. However, collisions...
In this work a gradient calibration method was presented as part of the Relative-Change-Based-Hierarchical Taxonomy (RCBHT) cantilever-snap verification system and the Pivot Approach control strategy for the automation of cantilever-snaps. As part of a relative-change based force signal interpretation scheme, an effective gradient calibration process is needed to increase the RCBHT's system robustness...
Autonomous snap assemblies is a highly desirable robotic functionality. While much work has been done in active sensing for peg-in-hole assemblies and general compliant motions, snap assembly state estimation remains an open research problem. This work presents a probabilistic framework designed to account for uncertainties in assembly and yield more intuitive and robust outcome assessments. Simulation...
Snap assembly automation remains a challenging task. While progress is being made in localization of parts, force controllers, and control strategies, little work has been done to help the robot reason about its current state, such that if necessary, the robot can assume corrective actions to accomplish the task. Error prone situations caused by the unexpected motion of parts, localization errors,...
This paper proposes an object placement planner for a grasped object during pick-and-place tasks. The proposed planner automatically determines the pose of an object stably placed near a user assigned point on an environment surface. The proposed method first constructs a polygon model of the surrounding environment, and then clusters the polygon model of both the environment and the object where...
Industrial snap assembly processes remain largely a manual task. Much of the research in snap assembly has not sought to design strategies and controllers according to the class of snap-fastener used. Three fastener types are used in manufacturing: cantilever, torsional, and annular snaps. As a first step in solving the snap automation problem, sought to devise a force control strategy that could...
The design of master manipulators for master-slave surgical robotic systems is important because it may influence slave manipulator performance as well as the operator's workload. However, no design strategy has been presented thus far for optimizing the master manipulator design parameters. A master manipulator prototype and an experimental setup were developed for investigating design parameter...
A surgical skill assessment system was developed to quantify microsurgical skills. Infrared optical makers, an inertial measurement unit, and strain gauges were mounted on tweezers to record surgical tasks. In preliminary experiments, the tool tip trajectory, acceleration, and applied force were measured and microsurgery videos were evaluated by three expert surgeons. The preliminary results indicated...
We propose new electromagnetic actuation of a microrobot by utilizing geometric constraints in a blood vessel. In our concept, a microrobot travels in a vascular network while keeping the contact to the vascular wall. In the paper, forces working on the microrobot are modeled in two dimensions, and conditions to propel the microrobot while pushing it against the vascular wall are described. The design...
Polarization encoding is one of encryption techniques that employ physical keys. Secret information is decoded without any calculations and can be distributed on social contacts. In this paper, we propose two types of compositions of polarization-encrypted sheets. A film-based type is composed of two quarter-wave retarder films that are attached together. The other type is composed of pieces of retarder...
We microscopically investigate the dynamics of magnetic domains and domain walls induced by a current pulse in Permalloy narrow wires by means of Lorentz microscopy and simultaneous transport measurement. A variety of magnetic domain and domain wall dynamics are induced as a function of current density flowing into the wire and wire resistance. Important finding is that observed magnetic domain wall...
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