Development of Control System for Colonoscopic Robot

2013 ◽  
Vol 278-280 ◽  
pp. 556-560
Author(s):  
Hai Yan Hu ◽  
Juan Li ◽  
Wei Dong Li ◽  
Wei Da Li ◽  
Li Ning Sun
Keyword(s):  
Minimally Invasive Surgery ◽  
Control System ◽  
Parallel Robot ◽  
Gastrointestinal Diseases ◽  
Distributed Structure ◽  
Continuum Robot ◽  
Good Potential ◽  
Continuum Structure ◽  
Upper Level ◽  
The Continuum

The continuum robot features continuously deformable backbone as opposed to traditional serial or parallel robot. It has good potential application in diagnose of gastrointestinal diseases and minimally invasive surgery. Aimed at the advantages of continuum robot, a colonoscopic robot with continuum structure is developed. In order to realize the control of colonoscopic robot, a control system with distributed structure is developed. The personal computer of this control system is constructed as upper level computer and the motion controllers based on DSP or ARM are used as lower level computer. The structure of colonoscopic robot is introduced in this paper. The kinematic base of control system is proposed. The control system, including the overall structure, the hardware and software, are analyzed respectively.

Analysis of a novel manipulator with low melting point alloy initiated stiffness variation and shape detection for minimally invasive surgery

2020 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Xiaoyong Wei ◽  
Feng Ju ◽  
Bai Chen ◽  
Hao Guo ◽  
Dan Wang ◽  
...  
Keyword(s):  
Minimally Invasive Surgery ◽  
Melting Point ◽  
Detection Method ◽  
Variable Stiffness ◽  
Shape Detection ◽  
Content Type ◽  
Continuum Robot ◽  
Stiffness Variation ◽  
Continuum Manipulator ◽  
The Continuum

Purpose There is an increasing popularity for the continuum robot in minimally invasive surgery owing to its compliance and dexterity. However, the dexterity takes the challenges in loading and precise control because of the absence of the shape tracking for the continuum robot. The purpose of this paper is to propose a new type of continuum manipulator with variable stiffness that can track the bending shape timely. Design/methodology/approach The low-melting-point alloy (LMPA) is used to implement the stiffness variation and shape detection for the continuum manipulator. A conceptual design for a single module is presented, and the principle of stiffness control based on the established static model is formulated. Afterward, a shape detection method is introduced in which the shape of the continuum manipulator can be detected by measuring the resistance of every LMPA. Finally, the effect of the proposed variable stiffness method is verified by simulation; the variable stiffness and shape detection methods are evaluated by experiments. Findings The results from the simulations and experiments indicate that the designed continuum manipulator has the ability of stiffness variation over 42.3% and the shape detection method has high precision. Originality/value Compared with conventional structures, the novel manipulator has a simpler structure and integrates the stiffness variation and shape detection capabilities with the LMPA. The proposed method is promising, and it can be conveniently extended to other continuum manipulators.

scholarly journals A Novel Discrete Wire-Driven Continuum Robot Arm with Passive Sliding Disc: Design, Kinematics and Passive Tension Control

Robotics ◽  
2019 ◽  
Vol 8 (3) ◽  
pp. 51 ◽  
Author(s):  
Yeshmukhametov ◽  
Koganezawa ◽  
Yamamoto
Keyword(s):  
Inverse Kinematics ◽  
Tension Control ◽  
Passive Tension ◽  
Robot Arm ◽  
Continuum Robot ◽  
Continuum Structure ◽  
Forward And Inverse Kinematics ◽  
The Wire ◽  
Pushing And Pulling ◽  
The Continuum

Wire-driven continuum manipulators are gaining more attention due to their flexibility and dexterity features. In comparison with traditional manipulators, the continuum structure is compliant and safe for human tissue and is able to easily adapt to the unstructured environment. Despite its advantages, wire-driven mechanisms have a serious problem with tension. While pushing and pulling, the wire loses tension, which leads to an ineffective way of driving the pulleys. Therefore, in this research, we propose a novel discrete continuum robot arm with a passive pre-tension mechanism that avoids the wire tension problem. Moreover, this paper will describe the backbone design of the discrete continuum arm and pre-tension mechanism structure, as well as forward and inverse kinematics and kinetic solutions, with simulation results.

scholarly journals Can Liquid Lenses Increase Depth of Field in Head Mounted Video See-Through Devices?

2021 ◽  
Vol 7 (8) ◽  
pp. 138
Author(s):  
Marina Carbone ◽  
Davide Domeneghetti ◽  
Fabrizio Cutolo ◽  
Renzo D’Amato ◽  
Emanuele Cigna ◽  
...  
Keyword(s):  
Control System ◽  
Clinical Practice ◽  
Augmented Reality ◽  
Time Of Flight ◽  
Depth Of Field ◽  
Liquid Lenses ◽  
Good Potential ◽  
Distance Sensor ◽  
Limited Depth ◽  
Lens Optics

Wearable Video See-Through (VST) devices for Augmented Reality (AR) and for obtaining a Magnified View are taking hold in the medical and surgical fields. However, these devices are not yet usable in daily clinical practice, due to focusing problems and a limited depth of field. This study investigates the use of liquid-lens optics to create an autofocus system for wearable VST visors. The autofocus system is based on a Time of Flight (TOF) distance sensor and an active autofocus control system. The integrated autofocus system in the wearable VST viewers showed good potential in terms of providing rapid focus at various distances and a magnified view.

Design and Experimental Implementation of Longitudinal Control for a Platoon of Automated Vehicles

1998 ◽  
Vol 122 (3) ◽  
pp. 470-476 ◽  
Author(s):  
R. Rajamani ◽  
S. B. Choi ◽  
B. K. Law ◽  
J. K. Hedrick ◽  
R. Prohaska ◽  
...  
Keyword(s):  
Control System ◽  
Torque Converter ◽  
Stable Operation ◽  
Automated Vehicles ◽  
Longitudinal Control ◽  
The Public ◽  
Automated Highways ◽  
Experimental Implementation ◽  
Special Challenge ◽  
Upper Level

This paper presents the design and experimental implementation of a longitudinal control system for the operation of automated vehicles in platoons. The control system on each vehicle is designed to have a hierarchical structure and consists of an upper level controller and a lower level controller. The upper controller determines the desired acceleration for each vehicle in the platoon so as to maintain safe string-stable operation even at very small intervehicle spacing. The lower controller utilizes vehicle-specific parameters and determines the throttle and/or brake commands required to track the desired acceleration. A special challenge handled in the design of the lower level controller is low-speed operation that involves gear changes and torque converter dynamics. The paper also presents the design of longitudinal intra-platoon maneuvers that are required in order to allow any car in the platoon to make an exit. The paper presents extensive experimental results from the public NAHSC demonstration of automated highways conducted in August 1997 at San Diego, California. The demonstration included an eight-car platoon operating continuously over several weeks with passenger rides given to over a thousand visitors. The maneuvers demonstrated included starting the automated vehicles from complete rest, accelerating to cruising speed, allowing any vehicle to exit from the platoon, allowing new vehicles to join the platoon and bringing the platoon to a complete stop at the end of the highway. [S0022-0434(00)01903-1]

scholarly journals Damping Optimum-Based Design of Control Strategy Suitable for Battery/Ultracapacitor Electric Vehicles

Energies ◽  
2018 ◽  
Vol 11 (10) ◽  
pp. 2854 ◽  
Author(s):  
Danijel Pavković ◽  
Mihael Cipek ◽  
Zdenko Kljaić ◽  
Tomislav Mlinarić ◽  
Mario Hrgetić ◽  
...  
Keyword(s):  
Control System ◽  
Energy Storage ◽  
Electric Vehicle ◽  
Storage System ◽  
Energy Storage System ◽  
Hybrid Energy ◽  
Hybrid Energy Storage ◽  
Hybrid Energy Storage System ◽  
Dc Bus ◽  
Upper Level

This contribution outlines the design of electric vehicle direct-current (DC) bus control system supplied by a battery/ultracapacitor hybrid energy storage system, and its coordination with the fully electrified vehicle driveline control system. The control strategy features an upper-level DC bus voltage feedback controller and a direct load compensator for stiff tracking of variable (speed-dependent) voltage target. The inner control level, comprising dedicated battery and ultracapacitor current controllers, is commanded by an intermediate-level control scheme which dynamically distributes the upper-level current command between the ultracapacitor and the battery energy storage systems. The feedback control system is designed and analytical expressions for feedback controller parameters are obtained by using the damping optimum criterion. The proposed methodology is verified by means of simulations and experimentally for different realistic operating regimes, including electric vehicle DC bus load step change, hybrid energy storage system charging/discharging, and electric vehicle driveline subject to New European Driving Cycle (NEDC), Urban Driving Dynamometer Schedule (UDDS), New York Certification Cycle (NYCC) and California Unified Cycle (LA92), as well as for abrupt acceleration/deceleration regimes.

scholarly journals Deeply Buried Nuclei in the Infrared-luminous Galaxies NGC 4418 and Arp 220. II. Line Forests at λ = 1.4–0.4 mm and Circumnuclear Gas Observed with ALMA

2021 ◽  
Vol 923 (2) ◽  
pp. 240
Author(s):  
Kazushi Sakamoto ◽  
Sergio Martín ◽  
David J. Wilner ◽  
Susanne Aalto ◽  
Aaron S. Evans ◽  
...  
Keyword(s):  
Galactic Disk ◽  
Vibrationally Excited ◽  
Content Type ◽  
Counter Rotation ◽  
Luminous Galaxies ◽  
Line Absorption ◽  
Type Object ◽  
Upper Level ◽  
Array Imaging ◽  
The Continuum

Abstract We present the line observations in our Atacama Millimeter-Submillimeter Array imaging spectral scan toward three deeply buried nuclei in NGC 4418 and Arp 220. We cover 67 GHz in f rest = 215–697 GHz at about 0.″2 (30, 80 pc) resolution. All the nuclei show dense line forests; we report our initial line identification using 55 species. The line velocities generally indicate gas rotation around each nucleus, tracing nuclear disks of ∼100 pc in size. We confirmed the counter-rotation of the nuclear disks in Arp 220 and that of the nuclear disk and the galactic disk in NGC 4418. While the brightest lines exceed 100 K, most of the major lines and many 13C isotopologues show absorption against even brighter continuum cores of the nuclei. The lines with higher upper-level energies, including those from vibrationally excited molecules, tend to arise from smaller areas, indicating radially varying conditions in these nuclei. The outflows from the two Arp 220 nuclei cause blueshifted line absorption below the continuum level. The absorption mostly has small spatial offsets from the continuum peaks to indicate the outflow orientations. The bipolar outflow from the western nucleus is also imaged in multiple emission lines, showing the extent of ∼1″ (400 pc). Redshifted line absorption against the nucleus of NGC 4418 indicates either an inward gas motion or a small collimated outflow slanted to the nuclear disk. We also resolved some previous confusions due to line blending and misidentification.

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