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1 – 10 of over 43000Teleoperated minimally invasive surgical robots can significantly enhance a surgeon's accuracy, dexterity and visualization. However, current commercially available systems do not…
Abstract
Teleoperated minimally invasive surgical robots can significantly enhance a surgeon's accuracy, dexterity and visualization. However, current commercially available systems do not include significant haptic (force and tactile) feedback to the operator. This paper describes experiments to characterize this problem, as well as several methods to provide haptic feedback in order to improve surgeon's performance. There exist a variety of sensing and control methods that enable haptic feedback, although a number of practical considerations, e.g. cost, complexity and biocompatibility, present significant challenges. The ability of teleoperated robot‐assisted surgical systems to measure and display haptic information leads to a number of additional exciting clinical and scientific opportunities, such as active operator assistance through “virtual fixtures” and the automatic acquisition of tissue properties.
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M.K. O'Malley and R.O. Ambrose
Robonaut is a humanoid robot designed by the Robotic Systems Technology Branch at NASA's Johnson Space Center in a collaborative effort with Defense Advanced Research Projects…
Abstract
Robonaut is a humanoid robot designed by the Robotic Systems Technology Branch at NASA's Johnson Space Center in a collaborative effort with Defense Advanced Research Projects Agency. This paper describes the implementation of haptic feedback into Robonaut and Robosim, the computer simulation of Robotonaut. In the first experiment, we measured the effects of varying feedback to a teleoperator during a handrail grasp task. Second, we conducted a teleoperated task, inserting a flexible beam into an instrumented receptacle. In the third experiment, we used Robonaut to perform a two‐arm task where a compliant ball was translated in the robot's workspace. The experimental results are encouraging as the Dexterous Robotics Lab continues to implement force feedback into its teleoperator hardware architecture.
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QingHui Wang, Zhong-Dong Huang, JingRong Li and Jia-Wu Liu
Realistic force sensation can help operators better feel and manipulate parts for virtual assembly (VA). Moreover, for VA of mechanical parts, it is necessary to consider their…
Abstract
Purpose
Realistic force sensation can help operators better feel and manipulate parts for virtual assembly (VA). Moreover, for VA of mechanical parts, it is necessary to consider their tolerance levels so as to apply proper assembly forces. Out of the three common assembly fit types, the type of clearance fit is the focus of virtual manual assembly, as parts with such fit type require precise force feedback to assist users’ assembly operations.
Design/methodology/approach
This study proposes a novel force rendering model for VA of mechanical parts with clearance fits. By decomposing an actual assembly operation into three consecutive states, the corresponding forces are formulated.
Findings
A prototype system is designed and developed to implement the model, and comparative case studies are conducted to investigate the users’ performance with the other three common approaches, namely, a typical WIMP (window-icon-menu-pointer) interface with CAD software, a physics simulation with collision detection and the approach that combines physics simulation and geometric constraints restriction. The results have shown that the proposed model is more realistic by providing continuous and realistic force feedback to the users.
Originality/value
The users’ feeling of immersion and their operational efficiency are greatly enhanced with the force sensation provided.
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Electrohydraulic servos have been widely applied to the task of precisely positioning heavy loads. Common examples from the military field are radar antenna and rocket engine…
Abstract
Electrohydraulic servos have been widely applied to the task of precisely positioning heavy loads. Common examples from the military field are radar antenna and rocket engine swivelling drives. In the commercial area large machine tool position controls are a prime example. Even with relatively substantial driving linkages, the inertia of these loads frequently results in low natural frequency of the output load‐driver structure. Very commonly this is combined with extremely small natural damping forces. Natural frequencies from 5 to 20 c.p.s. with damping ratios in the oder of 0·05 critical are typical. This combination of resonance with low damping creates a severe stability and performance problem for the electrohydraulic servo drive. Efforts to deal with this problem have centred on introducing artificial damping. In the past this has been done either by use of a controlled piston by‐pass leakage path or by use of a load force feedback path. The former technique is simple but wasteful with respect to power and inherently involves serious performance compromises. The latter technique can be arranged to be unassailable on theoretical grounds. However, it leads to severe system complication and large incremental hardware requirements. Questions of a reliability penalty are raised. A new technique has been developed which possesses all the performance advantages of load feedback without serious increase in complexity. Called Dynamic Pressure Feedback, this technique involves only a modification of servo valve component. It utilizes for feedback purposes the inherently high load forces developed as piston differential pressures, insuring reliable operation. The pressures needed are already available at the valve. No new hydraulic or electrical connexions are added. The performance advantages adduced for the Dynamic Pressure Feedback Servo Valve have been confirmed in carefully controlled comparative tests on a typical load system. Correspondence of test data with analytical prediction is good. A sufficient number of Dynamic Pressure Feedback Servo Valves have been produced on a pilot production line and installed in several applications in the field to insure producibility and design reliability.
Omer Faruk Argin and Zeki Yagiz Bayraktaroglu
This paper aims to present a novel modular design framework for the haptic teleoperation of single-master/multiple-slave (SM/MS) systems with cooperating manipulators.
Abstract
Purpose
This paper aims to present a novel modular design framework for the haptic teleoperation of single-master/multiple-slave (SM/MS) systems with cooperating manipulators.
Design/methodology/approach
The user commands the remote-leader robot and the slave remote robot follows the leader in a leader–follower formation. The remote-slave is purely force-controlled. A virtual model of the remote environment is introduced between the local and remote environments through simulation software. Locally generated motion inputs are transmitted to the remote environment through the virtual model. A haptic coupling is designed in the virtual environment and the haptic feedback is transmitted to the user along with the forces measured in the remote environment. The controllers proposed in this work are experimentally evaluated with experienced and inexperienced users.
Findings
The proposed haptic interaction model contributes to the total force feedback and smoothens the high-frequency signals occurring at the physical interaction in the remote environment. Experimental results show that the implemented controllers including the proposed haptic interaction improve the teleoperation performances in terms of trajectory tracking. Furthermore, pure force control of the remote-slave is shown to enhance the robustness of the teleoperation against external disturbances. Satisfactory teleoperation performances are observed with both experienced and inexperienced users.
Originality/value
The proposed SM/MS teleoperation system involves a multi-purpose virtual simulator and a purely force-controlled remote-slave manipulator in a modular cooperative configuration. The uniquely defined structure of the proposed haptic coupling is used in modeling the interaction between the local and remote manipulators on the one hand, and between cooperating remote manipulators on the other.
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Pinjun Xia, António Lopes and Maria Restivo
Haptics can significantly enhance the user's sense of immersion and interactivity. Especially in an assembly task, haptic feedback can help designers to have a better…
Abstract
Purpose
Haptics can significantly enhance the user's sense of immersion and interactivity. Especially in an assembly task, haptic feedback can help designers to have a better understanding of virtual objects and to increase task efficiency. The purpose of this paper is to investigate the design and implementation of a haptic‐based virtual assembly system (HVAS).
Design/methodology/approach
A multi‐thread system structure was designed, an automatic data integration interface was developed to transfer geometry, topology, assembly and physics information from a computer‐aided design system to virtual reality application, and a hierarchical constraint‐based data model and scene graph structure was designed to construct the virtual assembly environment. Unlike traditional virtual assembly systems based on collision detection or geometry constraint only, a physics‐based modeling approach combining with haptic feedback and geometry constraint was undertaken to realize and guide the realistic assembly process. When two parts collide into each other, the force and torque can be computed and provide feedback, and a spring‐mass model is used to prevent penetration and simulate dynamic behaviour. When two parts are close enough to each other and the assembly simulation state is activated, a geometry constraint can be captured, an attractive force can be generated to guide the user to assemble the part along the correct position, and the repulsive force can also be generated to realize the mating process as natural and realistic as in real life.
Findings
The implementation details and application examples demonstrate that haptic‐based virtual assembly is a valuable tool for assembly design and process planning.
Originality/value
The paper presents an HVAS.
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The field of organization development is about change and development of organizational systems. One of the major barriers to system change is organizational silence, the fear of…
Abstract
The field of organization development is about change and development of organizational systems. One of the major barriers to system change is organizational silence, the fear of lower level to speak truth to power, and senior leaders' reluctance to seek the truth. Consequently, senior leaders whose role is to orchestrate strategic change that will develop the organization's capabilities do not know the whole truth about their system's capabilities to achieve its purpose and strategy and live to its values. Thirty years of enabling leaders to transform their organization through safe honest, collective, and internally public conversations using a structured process called the Strategic Fitness Process (SFP) has led to insights about why such conversations are powerfully transformative. After a brief description of the SFP, this chapter describes insights and supporting grounded data about why honest conversations were transformative when leaders fully embrace the practice and spirit of SFP. These insights were gained from facilitating and observing hundreds of honest conversations in progress. The findings have implications for how leaders aided by consultants can accelerate strategic change that will improve effectiveness and performance while simultaneously transforming trust and commitment.
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The field of organization development is fragmented and lacks a coherent and integrated theory and method for developing an effective organization. A 20-year action research…
Abstract
The field of organization development is fragmented and lacks a coherent and integrated theory and method for developing an effective organization. A 20-year action research program led to the development and evaluation of the Strategic Fitness Process (SFP) – a platform by which senior leaders, with the help of consultants, can have an honest, collective, and public conversation about their organization's alignment with espoused strategy and values. The research has identified a syndrome of six silent barriers to effectiveness and a dynamic theory of organizational effectiveness. Empirical evidence from the 20-year study demonstrates that SFP always enables truth to speak to power safely, and in a majority of cases enables senior teams to transform silent barriers into strengths, realign their organization's design and strategic management process with strategy and values, and in a few cases employ SFP as an ongoing learning and governance process. Implications for organization and leadership development and corporate governance are discussed.
Philippe Desbats, Franck Geffard, Gérard Piolain and Alain Coudray
Aims to describe how to make an industrial robot work as a telemanipulator with force feedback, in order to carry out various tasks for remote handling in nuclear fuel cycle…
Abstract
Purpose
Aims to describe how to make an industrial robot work as a telemanipulator with force feedback, in order to carry out various tasks for remote handling in nuclear fuel cycle plants.
Design/methodology/approach
The robot Staübli RX170 (used as a slave arm) has been fitted with a force‐torque sensor and an electronic system for sensors' signals multiplexing. The overall system has been made tolerant to γ radiation up to a 10 kGy integrated dose. The industrial robot has been coupled to a master arm with force feedback capability and to the computer assisted teleoperation controller TAO2000 developed by CEA‐LIST.
Findings
The result of the maintenance operation reported in the paper, carried out with a Staübli RX170 robot at AREVA/COGEMA La Hague plant, illustrates the validity of this approach and demonstrates how remote handling can benefit from this new technology.
Originality/value
Introduces the teleoperation of industrial robots as a new solution for the maintenance of nuclear facilities. Wrist force/torque sensing and advanced master‐slave controller provide the operators with a high performance teleoperation system. Only limited modification of the existing design of the industrial robot has been carried out in order to transform it into a nuclear telemanipulator.
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Martin Culjat, Chih‐Hung King, Miguel Franco, James Bisley, Warren Grundfest and Erik Dutson
Robotic surgery is limited by the lack of haptic feedback to the surgeon. The addition of tactile information may enable surgeons to feel tissue characteristics, appropriately…
Abstract
Purpose
Robotic surgery is limited by the lack of haptic feedback to the surgeon. The addition of tactile information may enable surgeons to feel tissue characteristics, appropriately tension sutures, and identify pathologic conditions. Tactile feedback may also enable expansion of minimally invasive surgery to other surgical procedures and decrease the learning curve associated with robotic surgery. This paper aims to explore a system to provide tactile feedback.
Design/methodology/approach
A pneumatic balloon‐based system has been developed to provide tactile feedback to the fingers of the surgeon during robotic surgery. The system features a polydimethyl siloxane actuator with a thin‐film silicone balloon membrane and a compact pneumatic control system. The 1.0 × 1.8 × 0.4 cm actuators designed for the da Vinci system feature a 3 × 2 array of 3 mm inflatable balloons.
Findings
The low‐profile pneumatic system and actuator have been mounted directly onto the da Vinci surgical system. Human perceptual tests have indicated that pneumatic balloon‐based tactile input is an effective means to provide tactile information to the fingers of the surgeon.
Research limitations/implications
Application of a complete tactile feedback system is limited by current force sensing technologies.
Originality/value
The actuators have been designed such that they can be mounted directly onto the hand controls of the da Vinci robotic system, and are scalable such that they can be applied to various robotic applications.
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