Design and Performance Study of a Novel Minimally Invasive Active Surgical Needle

2019 ◽  
Vol 13 (4) ◽  
Author(s):  
Zahra Khashei Varnamkhasti ◽  
Bardia Konh
Keyword(s):  
Experimental Tests ◽  
Needle Insertion ◽  
Integrated System ◽  
Performance Study ◽  
Medical Treatments ◽  
Tissue Phantom ◽  
Sma Actuator ◽  
Potential Improvement ◽  
And Performance ◽  
And Control

Abstract Many medical treatments such as brachytherapy, thermal ablation, and biopsy are performed using percutaneous needle-based procedures. The success of these procedures highly depends on accurate placement of the needle tip at target positions. A novel active needle was designed and developed in this work that can steer inside the tissue via a shape memory alloy (SMA) actuator attached to its body. With actuation and control offered by the actuator, the active needle can reach the target positions with more accuracy, and thereby potential improvement in clinical outcomes. An integrated system was also developed to robotically operate the active needle insertion. The performance of the active needle was evaluated with finite element methods and experimental tests on a fabricated prototype in air. Active needle insertion tests in a tissue phantom were also performed to evaluate the performance of the active needle. The deflection in air and tissue phantom demonstrated the capability of the active needle to reach target positions.

Design and Performance Study of a 3-DOF Micropositioning Table

2006 ◽  
Vol 315-316 ◽  
pp. 450-454
Author(s):  
Yan Ling Tian ◽  
Da Wei Zhang ◽  
Cheng Zu Ren ◽  
Bing Yan
Keyword(s):  
Control Method ◽  
Piezoelectric Actuators ◽  
Experimental Tests ◽  
Control Voltage ◽  
Performance Study ◽  
Coupling Characteristic ◽  
And Performance ◽  
Grinding Machine ◽  
Relationship Of ◽  
Wheel Vibration

In order to implement dynamic compensation for the wheel vibration of surface grinding machine, a micropositioning table with high stiffness and response frequency is designed. The micropositioning table is driven by three piezoelectric actuators with stiffness of 400 N/μm. Three capacitive sensors are utilized to form feedback control and flexure hinges are used to guide the moving part and preload for the piezoelectric actuators. The kinetics of the micropositioning table has been analyzed to understand the relationship of the control voltage and the posture of the moving part. Due to the coupling characteristic of the system, the decoupling control method is introduced to improve the performance of the table. Experimental tests are carried out to investigate the performance of the micropositioning table.

Transitional flight equilibrium and performance study for the X-NMRL tail-sitter VTOL MAV

2018 ◽  
Vol 233 (8) ◽  
pp. 3056-3077 ◽  
Author(s):  
Wei Tang ◽  
Bi-Feng Song
Keyword(s):  
Estimation Method ◽  
Micro Air Vehicles ◽  
Control Surface ◽  
Iteration Algorithm ◽  
Performance Study ◽  
Aerodynamic Model ◽  
Flight Path Angle ◽  
And Performance ◽  
Full Throttle ◽  
And Control

An investigation on transitional flight equilibrium, performance analysis and parameter impacts is conducted in a conversion corridor, based on the proposed X-NMRL tail-sitter Vertical Takeoff and Landing Micro Air Vehicles (VTOL MAVs). Dependent on a propulsion model, aerodynamic model and physical control model, a nonlinear mathematical transitional model of the vehicle dynamics was constructed with consideration of the velocity, angle of attack, thrust, control surface deflection and pitching angle. The momentum theory and estimation method are applied to simulated propeller slipstream effects on aerodynamics, and an aerodynamic model for all regions of angles of attack and velocities is built. The nonlinear indefinite high-order dynamic model is solved by the improved Newton iteration algorithm. The corridor of the pitching angle or flight-path angle to the velocity reveals that the boundaries are mainly governed by the stalling performance, full throttle thrust and zero thrust, respectively. The performance corridor indicates different performance parameter variations under different conditions of steady climbing, cruising and descending states. Additionally, the performance for a steady transitional strategy can be illustrated to some extent. In terms of the parameter impacts, the increasing max propulsive power, supplied voltage, and decreasing total weight can widen the transitional corridor effectively, and the changes in the aerodynamics will only move the boundaries toward the same direction. These results will benefit transitional vehicle designs and control designs.

Robust Stability and Performance Study of Suboptimal H_∞ Control on a Benchmark Mechanical System

2018 ◽  
Author(s):  
Muhammad Auwal Shehu ◽  
Ahmad Bala Alhassan ◽  
Adisa Kehinde Olayinka ◽  
Ogunfowora Adeleke Rahmon
Keyword(s):  
Robust Stability ◽  
External Disturbance ◽  
Parametric Uncertainty ◽  
Order Reduction ◽  
Performance Study ◽  
Control Effort ◽  
Hankel Norm ◽  
And Performance ◽  
Mass Spring ◽  
And Control

The research paper focuses on studying the robust stability and performance of suboptimal H_∞ control on mass-spring-dashpot systems subject to parametric uncertainty and external disturbance on output response. The objective is keeping the vertical oscillation of the system constant under uncertainty and disturbance. For the control system to achieve satisfactory performance, suitable weighting filter functions for performance and control effort were designed respectively. Model order reduction for the synthesized controller based on Hankel norm approximation was conducted where a third order controller is obtained. Numerical results based on µ-analysis, frequency response and transient response show that the closed-system achieved robust stability and robust performance to parametric uncertainty and disturbance at all frequencies over the entire frequency bandwidth of study.

A hand-held robotic device for peripheral intravenous catheterization

2017 ◽  
Vol 231 (12) ◽  
pp. 1165-1177 ◽  
Author(s):  
Zhuoqi Cheng ◽  
Brian L Davies ◽  
Darwin G Caldwell ◽  
Giacinto Barresi ◽  
Qinqi Xu ◽  
...  
Keyword(s):  
Success Rate ◽  
Low Cost ◽  
Young Patients ◽  
Needle Insertion ◽  
Robotic Device ◽  
Design Development ◽  
Medical Treatments ◽  
Impedance Sensor ◽  
And Control ◽  
Intravenous Catheterization

Intravenous catheterization is frequently required for numerous medical treatments. However, this process is characterized by a high failure rate, especially when performed on difficult patients such as newborns and infants. Very young patients have small veins, and that increases the chances of accidentally puncturing the catheterization needle directly through them. In this article, we present the design, development and experimental evaluation of a novel hand-held robotic device for improving the process of peripheral intravenous catheterization by facilitating the needle insertion procedure. To our knowledge, this design is the first hand-held robotic device for assisting in the catheterization insertion task. Compared to the other available technologies, it has several unique advantages such as being compact, low-cost and able to reliably detect venipuncture. The system is equipped with an electrical impedance sensor at the tip of the catheterization needle, which provides real-time measurements used to supervise and control the catheter insertion process. This allows the robotic system to precisely position the needle within the lumen of the target vein, leading to enhanced catheterization success rate. Experiments conducted to evaluate the device demonstrated that it is also effective to deskill the task. Naïve subjects achieved an average catheterization success rate of 88% on a 1.5 mm phantom vessel with the robotic device versus 12% with the traditional unassisted system. The results of this work prove the feasibility of a hand-held assistive robotic device for intravenous catheterization and show that such device has the potential to greatly improve the success rate of these difficult operations.

Replication of the Superstition and Performance Study by

2014 ◽  
Vol 45 (3) ◽  
pp. 239-245 ◽  
Author(s):  
Robert J. Calin-Jageman ◽  
Tracy L. Caldwell
Keyword(s):  
Task Difficulty ◽  
Statistical Power ◽  
Meta Analysis ◽  
A Priori ◽  
Significant Heterogeneity ◽  
Performance Study ◽  
Improve Performance ◽  
Research Designs ◽  
Series Of Experiments ◽  
And Performance

A recent series of experiments suggests that fostering superstitions can substantially improve performance on a variety of motor and cognitive tasks ( Damisch, Stoberock, & Mussweiler, 2010 ). We conducted two high-powered and precise replications of one of these experiments, examining if telling participants they had a lucky golf ball could improve their performance on a 10-shot golf task relative to controls. We found that the effect of superstition on performance is elusive: Participants told they had a lucky ball performed almost identically to controls. Our failure to replicate the target study was not due to lack of impact, lack of statistical power, differences in task difficulty, nor differences in participant belief in luck. A meta-analysis indicates significant heterogeneity in the effect of superstition on performance. This could be due to an unknown moderator, but no effect was observed among the studies with the strongest research designs (e.g., high power, a priori sampling plan).

The role of copper ions in hydrogen peroxide bleaching: Their origin, removal, and effect on pulp quality

TAPPI Journal ◽  
2012 ◽  
Vol 11 (7) ◽  
pp. 37-46 ◽  
Author(s):  
PEDRO E.G. LOUREIRO ◽  
SANDRINE DUARTE ◽  
DMITRY V. EVTUGUIN ◽  
M. GRAÇA V.S. CARVALHO
Keyword(s):  
Hydrogen Peroxide ◽  
Copper Ions ◽  
Peroxide Bleaching ◽  
Metals Removal ◽  
Peroxide Decomposition ◽  
Equipment Corrosion ◽  
And Performance ◽  
And Control ◽  
Main Effects

This study puts particular emphasis on the role of copper ions in the performance of hydrogen peroxide bleaching (P-stage). Owing to their variable levels across the bleaching line due to washing filtrates, bleaching reagents, and equipment corrosion, these ions can play a major role in hydrogen peroxide decomposition and be detrimental to polysaccharide integrity. In this study, a Cu-contaminated D0(EOP)D1 prebleached pulp was subjected to an acidic washing (A-stage) or chelation (Q-stage) before the alkaline P-stage. The objective was to understand the isolated and combined role of copper ions in peroxide bleaching performance. By applying an experimental design, it was possible to identify the main effects of the pretreatment variables on the extent of metals removal and performance of the P-stage. The acid treatment was unsuccessful in terms of complete copper removal, magnesium preservation, and control of hydrogen peroxide consumption in the following P-stage. Increasing reaction temperature and time of the acidic A-stage improved the brightness stability of the D0(EOP)D1AP bleached pulp. The optimum conditions for chelation pretreatment to maximize the brightness gains obtained in the subsequent P-stage with the lowest peroxide consumption were 0.4% diethylenetriaminepentaacetic acid (DTPA), 80ºC, and 4.5 pH.

Concept and principles of building an integrated system of management of activities of regional gas supply system entities Kaliningrad region

2019 ◽  
pp. 64-72
Author(s):  
G.G. Arunyants
Keyword(s):  
Control System ◽  
Natural Gas ◽  
Supply System ◽  
Integrated System ◽  
Software Complex ◽  
Geographically Distributed ◽  
Basic Solutions ◽  
Kaliningrad Region ◽  
And Control ◽  
Gas Supply

The results of analysis of problems of regulation of gas supply complex of Kaliningrad region and main ways to increase its efficiency, as well as basic solutions for creation of a software complex Т-GAZ-2 automated calculation of natural gas tariffs for ACS of gas supply system subjects, geographically distributed and information connected to the regional automated information and control system (RAIS).

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