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Sassenheim, Netherlands

Heemskerk C.J.M.,Heemskerk Innovative Technology BV | Elzendoorn B.S.Q.,EURATOM | Magielsen A.J.,Nuclear Research and Consultancy Group | Schropp G.Y.R.,University Utrecht
Fusion Engineering and Design | Year: 2011

A new facility has been taken in operation to investigate the influence of visual and haptic feedback on the performance of remotely executed ITER RH maintenance tasks. A reference set of representative ITER remote handling maintenance tasks was included the master slave manipulator system (MS2) benchmark product. The benchmark product was used in task performance tests in a representative two-handed dexterous manipulation test bed at NRG. In the setup, the quality of visual feedback was varied by exchanging direct view with indirect view setups in which visual feedback is provided via video cameras. Interaction forces were measured via an integrated force sensor. The impact of feedback quality on the performance of maintenance tasks at the level of handling individual parts was measured and analysed. Remote execution of the maintenance actions took roughly 3-5 times more time than hands-on. Visual feedback was identified as the dominant factor, including aspects like (lack of) operator control over camera placement, pan, tilt and zoom, lack of 3D perception, image quality, and latency. Haptic feedback was found to be important, but only in specific contact transition and constrained motion tasks. © 2011 Elsevier B.V. All rights reserved. Source

Boessenkool H.,FOM Institute DIFFER | Boessenkool H.,TU Eindhoven | Abbink D.A.,Technical University of Delft | Heemskerk C.J.M.,Heemskerk Innovative Technology BV | And 2 more authors.
IEEE Transactions on Haptics | Year: 2013

Telemanipulation allows human to perform operations in a remote environment, but performance and required time of tasks is negatively influenced when (haptic) feedback is limited. Improvement of transparency (reflected forces) is an important focus in literature, but despite significant progress, it is still imperfect, with many unresolved issues. An alternative approach to improve teleoperated tasks is presented in this study: Offering haptic shared control in which the operator is assisted by guiding forces applied at the master device. It is hypothesized that continuous intuitive interaction between operator and support system will improve required time and accuracy with less control effort, even for imperfect transparency. An experimental study was performed in a hard-contact task environment. The subjects were aided by the designed shared control to perform a simple bolt-spanner task using a planar three degree of freedom (DOF) teleoperator. Haptic shared control was compared to normal operation for three levels of transparency. The experimental results showed that haptic shared control improves task performance, control effort and operator cognitive workload for the overall bolt-spanner task, for all three transparency levels. Analyses per subtask showed that free air movement (FAM) benefits most from shared control in terms of time performance, and also shows improved accuracy. © 2013 IEEE. Source

Wildenbeest J.G.W.,Technical University of Delft | Wildenbeest J.G.W.,Heemskerk Innovative Technology BV | Abbink D.A.,Technical University of Delft | Boessenkool H.,Institute for Energy and Transport of the Netherlands | And 4 more authors.
Fusion Engineering and Design | Year: 2013

Haptic shared control is a promising approach to increase the effectiveness of remote handling operations. While in haptic shared control the operator is continuously guided with assistive forces, the operator's response to forces is not fully understood. This study describes the development of a computational model of a human operator controlling a teleoperation system based on feedforward control. In a simulation, the operator's response to repulsive forces in free-space motions was modeled for two degrees of freedom, for two operator endpoint admittances (estimated by means of closed-loop identification techniques). The simulation results show that similar repulsive forces lead to substantial discrepancies in response when admittance settings mismatch; wrongly estimated operator admittances can lead to assistive forces that are either not perceived, or deflect the combined system of human operator and telemanipulator. It is concluded that assistive forces should be tailored to the arm configuration and the type of task performed. In order to utilize haptic shared control to its full potential, it is required to study, measure and quantitatively model operator behavior for teleoperated tasks in more detail. © 2013 Elsevier B.V. Source

Wildenbeest J.G.W.,Technical University of Delft | Wildenbeest J.G.W.,Heemskerk Innovative Technology BV | Abbink D.A.,Technical University of Delft | Heemskerk C.J.M.,Heemskerk Innovative Technology BV | And 3 more authors.
IEEE Transactions on Haptics | Year: 2013

In teleoperation, haptic feedback allows the human operator to touch the remote environment. Yet, it is only partially understood to what extent the quality of haptic feedback contributes to human-in-the-loop task performance. This paper presents a human factors experiment in which teleoperated task performance and control effort are assessed for a typical (dis-)assembly task in a hard-to-hard environment, well known to the operator. Subjects are provided with four levels of haptic feedback quality: no haptic feedback, low-frequency haptic feedback, combined low- and high-frequency haptic feedback, and the best possible-a natural spectrum of haptic feedback in a direct-controlled equivalent of the task. Four generalized fundamental subtasks are identified, namely: 1) free-space movement, 2) contact transition, 3) constrained translational, and 4) constrained rotational tasks. The results show that overall task performance and control effort are primarily improved by providing low-frequency haptic feedback (specifically by improvements in constrained translational and constrained rotational tasks), while further haptic feedback quality improvements yield only marginal performance increases and control effort decreases, even if a full natural spectrum of haptic feedback is provided. © 2008-2011 IEEE. Source

Van Oosterhout J.,Technical University of Delft | Abbink D.A.,Technical University of Delft | Koning J.F.,Heemskerk Innovative Technology BV | Boessenkool H.,EURATOM | And 3 more authors.
Fusion Engineering and Design | Year: 2013

A promising solution to improve task performance in ITER hot cell remote handling is the use of haptic shared control. Haptic shared control can assist the human operator along a safe and optimal path with continuous guiding forces from an intelligent autonomous controller. Previous research tested such controllers with accurate knowledge of the environment (giving flawless guiding forces), while in a practical implementation guidance forces will sometimes be flawed due to inaccurate models or sensor information. This research investigated the effect of zero and small (7.5 mm) errors on task performance compared to normal (unguided) operation. In a human factors experiment subjects performed a three dimensional virtual reality peg-in-hole type task (30 mm diameter; 0.1 mm clearance), with and without - potentially flawed - haptic shared control. The results showed that the presence of guiding forces, despite of small guiding errors, still improved task performance with respect to unguided operations. © 2012 Elsevier B.V. Source

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