document

Fall detection in walking robots by multi-way principal component analysis

Karssen, J.G. (author), Wisse, M. (author)

Large disturbances can cause a biped to fall. If an upcoming fall can be detected, damage can be minimized or the fall can be prevented. We introduce the multi-way principal component analysis (MPCA) method for the detection of upcoming falls. We study the detection capability of the MPCA method in a simulation study with the simplest walking...

journal article 2008

document

Can a structured checklist prevent problems with laparoscopic equipment?

Verdaasdonk, E.G.G. (author), Stassen, L.P.S. (author), Hoffmann, W.F. (author), Van der Elst, M. (author), Dankelman, J. (author)

Background A high incidence of problems with the technical equipment is known to occur during routine laparoscopic procedures. Use of a structured checklist of preparatory measures could help to prevent these problems. This study aimed to determine the extent to which a checklist reduced the number of incidents with technical laparoscopic...

journal article 2008

document

Requirements for the design and implementation of checklists for surgical processes

Verdaasdonk, E.G.G. (author), Stassen, L.P.S. (author), Widhiasmara, P.P. (author), Dankelman, J. (author)

Background- The use of checklists is a promising strategy for improving patient safety in all types of surgical processes inside and outside the operating room. This article aims to provide requirements and implementation of checklists for surgical processes. Methods- The literature on checklist use in the operating room was reviewed based on...

journal article 2008

document

Human error in strabismus surgery: Quantification with a sensitivity analysis

Schutte, S. (author), Polling, J.R. (author), Van der Helm, F.C.T. (author), Simonsz, H.J. (author)

Background- Reoperations are frequently necessary in strabismus surgery. The goal of this study was to analyze human-error related factors that introduce variability in the results of strabismus surgery in a systematic fashion. Methods- We identified the primary factors that influence the outcome of strabismus surgery. For each of the human...

journal article 2008

document

An Electric Scooter Simulation Program for Training the Driving Skills of Stroke Patients with Mobility Problems: A Pilot Study

Jannink, M.J.A. (author), Erren-Wolters, C.V. (author), De Kort, A.C. (author), Van der Kooij, H. (author)

This paper describes an electric scooter simulation program and a first evaluation study in which we explored if it is possible to train the driving skills of future users of electric mobility scooters by means of an electric scooter simulation program in addition to conventional electric scooter training. Within this explorative study, 10...

journal article 2008

document

Impact of early applied upper limb stimulation: The EXPLICIT-stroke programme design

Kwakkel, G. (author), Meskers, C.G.M. (author), Van Wegen, E.E. (author), Lankhorst, G.J. (author), Geurts, A.C.H. (author), Van Kuijk, A.A. (author), Lindeman, E. (author), Visser-Meily, A. (author), Vlugt, E. (author), Arendzen, J.H. (author)

Main claims of the literature are that functional recovery of the paretic upper limb is mainly defined within the first month post stroke and that rehabilitation services should preferably be applied intensively and in a task-oriented way within this particular time window. EXplaining PLastICITy after stroke (acronym EXPLICIT-stroke) aims to...

journal article 2008

document

Advancing simulation-based driver training

De Winter, J.C.F. (author)

doctoral thesis 2009

document

The monosynaptic Ia afferent pathway can largely explain the stretch duration effect of the long latency M2 response

Schuurmans, J. (author), De Vlugt, E. (author), Schouten, A.C. (author), Meskers, C.G. (author), De Groot, J.H. (author), Van der Helm, F.C.T. (author)

Sudden stretch of active muscle typically results in two characteristic electromyographic responses: the short latency M1 and the long latency M2. The M1 response originates from the monosynaptic Ia afferent reflex pathway. The M2 response is less well understood and is likely a compound response to different afferent inputs mediated by spinal...

journal article 2009

document

Sensory Weighting of Force and Position Feedback in Human Motor Control Tasks

Mugge, W. (author), Schuurmans, J. (author), Schouten, A.C. (author), Van der Helm, F.C.T. (author)

In daily life humans integrate force and position feedback from mechanoreceptors, proprioception, and vision. With handling relatively soft, elastic objects, force and position are related and can be integrated to improve the accuracy of an estimate of either one. Sensory weighting between different sensory systems (e.g., vision and...

journal article 2009

document

Energy efficient walking with central pattern generators: From passive dynamic walking to biologically inspired control

Verdaasdonk, B.W. (author), Koopman, H.F.J.M. (author), Van der Helm, F.C.T. (author)

Like human walking, passive dynamic walking—i.e. walking down a slope with no actuation except gravity—is energy efficient by exploiting the natural dynamics. In the animal world, neural oscillators termed central pattern generators (CPGs) provide the basic rhythm for muscular activity in locomotion. We present a CPG model, which automatically...

journal article 2009

document

A Semianalytical Approach to Large Deflections in Compliant Beams under Point Load

Tolou, N. (author), Herder, J.L. (author)

The deflection of compliant mechanism (CM) which involves geometrical nonlinearity due to large deflection of members continues to be an interesting problem in mechanical systems. This paper deals with an analytical investigation of large deflections in compliant mechanisms. The main objective is to propose a convenient method of solution for...

journal article 2009

document

Muscle weakness and lack of reflex gain adaptation predominate during post-stroke posture control of the wrist

Meskers, C.G.M. (author), Schouten, A.C. (author), De Groot, J.H. (author), De Vlugt, E. (author), Van Hilten, B.J.J. (author), Van der Helm, F.C.T. (author), Arendzen, H.J.H. (author)

Background Instead of hyper-reflexia as sole paradigm, post-stroke movement disorders are currently considered the result of a complex interplay between neuronal and muscular properties, modified by level of activity. We used a closed loop system identification technique to quantify individual contributors to wrist joint stiffness during an...

journal article 2009

document

First validation of the PASSPORT training environment for arthroscopic skills

Tuijthoff, G.J.M. (author), Van Sterkenburg, M.N. (author), Sierevelt, I.N. (author), Van Oldenrijk, J. (author), Van Dijk, C.N. (author), Kerkhoffs, G.M.M.J. (author)

The demand for high quality care is in contrast to reduced training time for residents to develop arthroscopic skills. Thereto, simulators are introduced to train skills away from the operating room. In our clinic, a physical simulation environment to Practice Arthroscopic Surgical Skills for Perfect Operative Real-life Treatment (PASSPORT) is...

journal article 2009

document

The videolaryngoscope is less traumatic than the classic laryngoscope for a difficult airway in an obese patient

Maassen, R. (author), Lee, R. (author), Van Zundert, A. (author), Cooper, R. (author)

This report describes the anesthetic management of an obese patient with a difficult airway and the merits of videolaryngoscopy, specifically in terms of the reduced risk of dental damage during intubation. A 49-year-old woman (body mass index; BMI, 36 kg·m?2), was scheduled to undergo an elective laparoscopic cholecystectomy because of...

journal article 2009

document

A rigorous model of reflex function indicates that position and force feedback are flexibly tuned to position and force tasks

Mugge, W. (author), Abbink, D.A. (author), Schouten, A.C. (author), Dewald, J.P.A. (author), Van der Helm, F.C.T. (author)

This study aims to quantify the separate contributions of muscle force feedback, muscle spindle activity and co-contraction to the performance of voluntary tasks (‘‘reduce the influence of perturbations on maintained force or position’’). Most human motion control studies either isolate only one contributor, or assume that relevant reflexive...

journal article 2009

document

Objective classification of residents based on their psychomotor laparoscopic skills

Chmarra, M.K. (author), Klein, S. (author), De Winter, J.C.F. (author), Jansen, F.W. (author), Dankelman, J. (author)

Background - From the clinical point of view, it is important to recognize residents’ level of expertise with regard to basic psychomotor skills. For that reason, surgeons and surgical organizations (e.g., Acreditation Council for Graduate Medical Education, ACGME) are calling for assessment tools that credential residents as technically...

journal article 2009

document

Augmented Reality for Art, Design and Cultural Heritage: System Design and Evaluation

Caarls, J. (author), Jonker, P. (author), Kolstee, Y. (author), Rotteveel, J. (author), Van Eck, W. (author)

This paper describes the design of an optical see-through head-mounted display (HMD) system for Augmented Reality (AR). Our goals were to make virtual objects “perfectly” indistinguishable from real objects, wherever the user roams, and to find out to which extent imperfections are hindering applications in art and design. For AR, fast and...

journal article 2009

document

Tizanidine does not affect the linear relation of stretch duration to the long latency M2 response of m. flexor carpi radialis

Meskers, C.G.M. (author), Schouten, A.C. (author), Rich, M.M.L. (author), De Groot, J.H. (author), Schuurmans, J. (author), Arendzen, J.H. (author)

The long latency M2 electromyographic response of a suddenly stretched active muscle is stretch duration dependent of which the nature is unclear. We investigated the inXuence of the group II aVerent blocker tizanidine on M2 response characteristics of the m. Xexor carpi radialis (FCR). M2 response magnitude and eliciting probability in a group...

journal article 2009

document

Discovery of high-level tasks in the operating room

Bouarfa, L. (author), Jonker, P.P. (author), Dankelman, J. (author)

Recognizing and understanding surgical high-level tasks from sensor readings is important for surgical workflow analysis. Surgical high-level task recognition is also a challenging task in ubiquitous computing because of the inherent uncertainty of sensor data and the complexity of the operating room environment. In this paper, we present a...

journal article 2010

document

An Isolator System for minimally invasive surgery: The new design

Horeman, T. (author), Jansen, F.W. (author), Dankelman, J. (author)

Background - The risk of obtaining a postsurgical infection depends highly on the air quality surrounding the exposed tissue, surgical instruments, and materials. Many isolators for open surgery have been invented to create a contained sterile volume around the exposed tissue. With the use of an isolator, a surgical procedure can be performed...

journal article 2010