Martínez-Ramírez A., Lecumberri P., Gómez M.,  et al

Frailty assessment based on wavelet analysis during quiet standing balance test

J Biomechanics
2011; 44(12): 2213-20

Link

MTx

Reininga I.H.F., Stevens M., Wagenmakers R.,  et al

Accuracy and reproducibility of a body-fixed-sensor based assessment of compensatory trunk movements and spatiotemporal gait parameters in patients with hip osteoarthritis

American J. of Phys Med and Rehab.
2011; 90(8): 681-687

Link

Xbus Kit

Berthouze L., Mayston M.

Design and validation of surface-marker clusters for the quantification of joint rotations in general movements in early infancy

J Biomechanics
2011;44(6):1212-5

Link

MVN BIOMECH

McDonald R.L., Wilson G.N., Molloy A., Franck L.S.

Feasibility of three electronic instruments in studying the benefits of adaptive seating

Disabil Rehabil Assist Technol.
2011; 6(6): 483-90.

Link

MTx

Paulis W.D., Horemans H.L.D., Brouwer B.S. Stam H.j.

Excellent test-retest and inter-rater reliability for Tardieu Scale measurements with inertial sensors in elbow flexors of stroke patients

To appear in Gait & Posture

Link

Xbus Kit

Krüg A., Edelmann-Nusser J.

Application of a Full Body Inertial Measurement in Alpine Skiing: A Comparison With an Optical Video Based System

J Appl Biomech.
2010; 26(4):516-21

Link

MVN BIOMECH

Hol J.D., Schön T.B., Gustafsson F.

Modeling and calibration of inertial and vision sensors

International Journal of Robotics Research,

Schepers, H.M., van Asseldonk, E.H.F., Baten, C.T.M., Veltink, P.H.

"Ambulatory Estimation of Foot Placement During Walking using Inertial Sensors"

J. Biomechanics
2010; 43:(16):3138-3143.

Link

Xsens ForceShoe

Faber, G. S., Kingma, I., van Diëen, J. H.

“Bottom-up estimation of joint moments during manual lifting using orientation sensors instead of position sensors”

J. Biomechanics
2010;43:1432–1436

Link

Xsens ForceShoe

Faber, G.S., Kingma, I., Schepers M.H., Veltink, P.H., van Diëen, J.H.

“Determination of joint moments with instrumented force shoes in a variety of tasks”

J. Biomechanics
2010;43:2848–2854

Link

Xsens ForceShoe

Supej M.

3D Measurements of alpine skiing with an inertial sensor motion capture suit and GNSS RTK system

Journal of Sports Sciences
2010; 28: 7, 759 — 769

Link

Xsens MVN

Cutti AG, Ferrari A, Garofalo P, et al

‘Outwalk’: a protocol for clinical gait analysis based on inertial & magnetic sensors

Med Bio Eng Comput
2010;48(1):17-25

Link

Xbus Kit

Ferrari A, Cutti AG, Garofalo P, et al.

First in-vivo assessment of ‘Outwalk’ – a novel protocol for clinical gait analysis based on inertial & magnetic sensors

Med Bio Eng Comput,
2010;48(1):1-15

Link

Xbus Kit

Schepers M.H., Veltink P.H.

Stochastic magnetic measurement model for relative position and orientation estimation

Meas. Sci. Technol. 21
2010 065801 (10pp)

Link

Schepers M.H., Roetenberg D., Veltink P.H.

Ambulatory human motion tracking by fusion of inertial and magnetic sensing with adaptive actuation

Med Bio Eng Comput,
2010;48:27–37

Link

Martínez-Ramírez A., Lecumberri P., Gómez M., Izquierdo M.

Wavelet analysis based on time-frequency information discriminate chronic ankle instability

Clin Biomech.
2010;25(3):256-64

Link

MTx

Micera S. , Sabatini A.M., Genovese V., et al.

Assessment technologies for the analysis of the efficacy of a Vestibular Neural Prosthesis

Link

MTx

Saber-Sheikh K., Bryant E.C., Glazzard C., Hamel A., Lee R.Y.

Feasibility of using inertial sensors to assess human movement

Man Ther.
2010;15(1):122-5

Link

Lab link

MTx

Schepers, M.H., van Asseldonk, E.H.F, Buurke, J.H., Veltink, P.H.

Ambulatory Estimation of Center of Mass Displacement During Walking

IEEE Transactions on Biomedical Engineering
2009;56:1189-1195

Link

Xsens ForceShoe

Kruger A., Edelmann-Nusser J.

Biomechanical analysis in freestyle snowboarding: application of a full-body inertial measurement system and a bilateral insole measurement system

Sports Technol.
2009; 2 (1–2):17–23

DOI: 10.1002/jst.89

Link

MVN

Schepers M.H., van Asseldonk E.H.F., Buurke J.H., Veltink P.H.

Ambulatory Estimation of Center of Mass Displacement during Walking

IEEE Trans. on Bio Eng
2009; 56:1189-1195

Link

van der Noort JC, Scholtes VAB, Harlaar J

Evaluation of clinical spasticity assessment in cerebral palsy using inertial sensors

Gait & posture
2009; 30(2):138-143

Link

Xbus Kit

Veltink P.H., Kortier H., Schepers M.H.

Sensing Power Transfer Between the Human Body and the Environment

IEEE Trans. on Bio Eng
2009;56(6)

Link

Cutti AG, Giovanardi A, Rocchi L, Davalli A, Sacchetti R

Ambulatory measurement of shoulder and elbow kinematics through inertial and magnetic sensors

Med Bio Eng Comput
2008; 46:169–178

Link

Xbus Kit

Brodie M., Walmsley A., Page W.

Fusion motion capture: a prototype system using inertial measurement units and GPS for the biomechanical analysis of ski racing

Sports Technol.
2008; 1(1): 17–28

Link

Xbus Kit
Xsens MVN

Hol J.D., Schön T.B., Luinge H.J, Slycke P.J., Gustafsson F.

Robust real-time tracking by fusing measurements from inertial and vision sensors

J. Real-Time Image Processing
2007;2(2):149–160
doi: 10.1007/s11554-007-0040-2.

Chandaria J., Thomas G., Bartczak B., et al

Real-time camera tracking in the MATRIS project

SMPTE Motion Imaging Journal
2007;116(7–8):266–271

Liedtke C., Fokkenrood S.A.W., Menger J. T., van der Kooij H., Veltink P.H.

Evaluation of instrumented shoes for ambulatory assessment of ground reaction forces

Gait & Posture
2007;26:39–47

Link

Xsens ForceShoe

Schepers H.M., Koopman H.F.J.M., Veltink P.H.,

Ambulatory Assessment of Ankle and Foot Dynamics

IEEE Trans. Bio. Eng.
2007;54:895-902

Link

Xsens ForceShoe

Moore, S.T., MacDougall, H. G., Gracies, J. M., et al

Long-term monitoring of gait in Parkinson’s disease

Gait & Posture
2007; 26: 200–207

Link

MT9

Roetenberg D., Baten C.T.M., Veltink P.H.

Estimating Body Segment Orientation by Applying Inertial and Magnetic Sensing Near ferromagnetic Materials

IEEE Trans Neural Sys & Rehab Eng.
2007;15(3):469-471

Link

Schepers H.M., Koopman H.F.J.M., Veltink P.H

Ambulatory Assessment of Ankle and Foot Dynamics

IEEE Trans. on Bio Eng
2007;54(5):895–902

Link

Roetenberg D., Slycke P.J., Veltink P.H

Ambulatory Position and Orientation Tracking Fusing Magnetic and Inertial Sensing

IEEE Trans. on Bio Eng
2007;54(5):883–890

Link

Luinge H.J., Veltink P.H, Baten C.T.M.

Ambulatory measurement of arm orientation

J. Biomechanics
2007;40:78–85

Link

Roetenberg D., Luinge H.J., Baten C.T.M., Veltink P.H.

Compensation of Magnetic Disturbances Improves Inertial and Magnetic Sensing of Human Body Segment Orientation

IEEE Trans Neural Sys & Rehab Eng.
2005;(3)

Link

Roetenberg D., Luinge H.J., Veltink P.H.

Inertial and magnetic sensing of human movement near ferromagnetic materials

UNIVERSITY OF TWENTE ,THE NETHERLANDS

Link

Veltink P.H., Liedtke C., Droog A., van der Kooij H.

Ambulatory Measurement of Ground Reaction Forces

IEEE Trans Neural Sys & Rehab Eng.
2005;13:423-427

Link

Xsens ForceShoe

Veltink P.H., Slycke P.J., Hemssems J., Buschman R., Bultstra G., Hermens H.J.

Three dimensional inertial sensing of foot movements for automatic tuning of a two-channel implantable drop-foot stimulator

Med. Eng & Phys
2003; 25(1): 21-28.

Link

Reininga I.H.F., Stevens M., et al

Accuracy and reproducibity of a body-fixed-sensor based assessment of compensatory trunk movements and spatiotemporal gait parameters in patients with hip osteoarthritis

Poster ICAMPAM, May 24-27 2011, Glasgow, UK

Xbus Kit

Reininga I.H.F., Stevens M.,  et al

Patients with end-stage hip osteoarthritis show distinctive patterns of trunk movements during gait – a body-fixed-sensor based analysis

Proceeding ICAMPAM, May 24-27 2011, Glasgow, UK

Xbus Kit

Schepers M.H., Roetenberg D., Veltink P.H., Luinge H.J.

Continuous Center of Mass Displacement Estimation During Walking

Comparison between MVN and the ForceShoe

The 11th International Symposium on the 3-D Analysis of Human Movement

14 - 16 July2010, San Francisco, USA

Cloete, T.; Scheffer, C.

Repeatability of an off-the-shelf, full body inertial motion capture system during clinical gait analysis

Engineering in Medicine and Biology Society (EMBC), 2010 Annual International Conference of the IEEE 11 Nov 2010 pp 5125 - 5128

Link

Xsens MVN

Reininga I.H.F., Zijlstra W., et al

Test-retest reliability of a body-fixed sensor gait analysis protocol for evaluating trunk movements and gait parameters in patients with hip osteoarthritis

Poster ESMAC, September 16-19 2009, London, UK

Xbus Kit

Field, M.; Stirling, D.; Naghdy, F.; Zengxi Pan

Motion capture in robotics review

IEEE International Conference on Control and Automation, 2009. ICCA 2009  pp: 1697 - 1702

Digital Object Identifier: 10.1109/ICCA.2009.5410185

Xsens MVN

Reininga I.H.F., Stevens M., et al

Reliability of a body-fixed sensor gait analysis protocol for evaluating gait function in patients with hip osteoarthritis

Poster ICAMPAM, May 21-24 2008, Rotterdam, The Netherlands

Xbus Kit

Hol J.D., Schön T.B., Gustafsson F.

A new algorithm for calibrating a combined camera and IMU sensor unit

Proceedings of 10th International Conference on Control, Automation, Robotics and Vision, pages 1857–1862, Hanoi, Vietnam, Dec. 2008b.  doi: 10.1109/ICARCV.2008.4795810.

Hol J.D., Schön T.B., Gustafsson F.

Relative pose calibration of a spherical camera and an IMU

Proceedings of 8th International Symposium on Mixed and Augmented Reality,  pages 21–24, Cambridge, UK, Sept. 2008a. doi: 10.1109/ISMAR.2008.4637318.

Gustafsson F., Schön T. B.,  Hol J. D.

Sensor fusion for augmented reality

Proceedings of 17th International Federation of Automatic ControlWorld Congress, Seoul, South Korea, July 2008. doi: 10.3182/20080706-5-KR-1001.3059.

Hesami, A.; Naghdy, F.; Stirling, D.; Hill, H

Perception of human gestures through observing body movements

International Conference on Intelligent Sensors, Sensor Networks and Information Processing, 2008. ISSNIP 2008. pp 97 - 102

Digital Object Identifier: 10.1109/ISSNIP.2008.4761969

Xsens MVN

Field, M.; Stirling, D.; Naghdy, F.; Zengxi Pan

Mixture Model Segmentation for Gait Recognition

Symposium on Learning and Adaptive Behaviors for Robotic Systems, 2008. LAB-RS '08. ECSIS pp 3 - 8

Digital Object Identifier: 10.1109/LAB-RS.2008.26

Xsens MVN

Peter Vi.

Effectiveness of a drywall sanding machine reducing forceful exertions and repetitive motion

AHFE international conference 2008

Link

MTx

Renaudin, V., Yalak, O., Tomé P.

Hybridization of MEMS and assisted GPS for Pedestrian Navigation

Inside GNSS, January/February 2007

Link

Xbus Kit, MTx

Hol J. D., Schön T. B., Gustafsson F., Slycke P. J.

Sensor Fusion for Augmented Reality

Proceedings of 9th International Conference on Information Fusion, Florence, Italy, July 2006b. doi: 10.1109/ICIF.2006.301604.

Link

Sun C., Naghdy F., Stirling D.

Application of MML to Motor Skills Acquisition

International Conference On Computational Intelligence for Modelling, Control and Automation, 2006

Link

MTx

Hub, A., Hartter, T., Ertl, T.

Interactive Tracking of Movable Objects for the Blind on the Basis of Environment Models and Perception-Oriented Object Recognition Methods

Assets '06, Portland, USA, October 22–25, 2006

Link

MT9-B

Stiefmeier, T., Ogris, G., et al

Combining Motion Sensors and Ultrasonic Hands Tracking for Continuous Activity Recognition in a Maintenance Scenario

Wearable Computing Lab, ETH Zurich, Switzerland & Institute for Computer Systems and Networks, UMIT Innsbruck, Austria, 2006

Link

Xbus Kit

Thies, S.B., Tresadern, P., et al

Comparison of Linear Accelerations from three Measurements during reach and grasp

Centre for Rehabilitation and Human Performance Research, University of Salford, 2006

Link

Xbus Kit

Huiyu Zhou, Huosheng Hu, Yaqin Tao

Inertial measurements of upper limb motion

International Federation for Medical and Biological Engineering 2006, 31 May 2006

Link

MT9-B

Pfau T., Witte T.H., Wilson A. M.

A method for deriving displacement data during cyclical movement using an inertial sensor

The Journal Of Experimental Biology 208, By The Company Of Biologists 2005, April 25th 2005

Link

MT9

Heinz E. A., Kunze K, et al

Using Wearable Sensors for Real-time Recognition Tasks in Games of Martial Arts – An Initial Experiment

Institute for Computer Systems and Networks (CSN), Umit – University of Health Systems, Medical Informatics and Technology, Hall in Tyrol, Austria, 2005

Link

Xbus Kit, MT9

Kunze K, Barry M, et al

Towards Recognizing Tai Chi – An Initial Experiment Using Wearable Sensors

Institute for Computer Systems and Networks CSN), Umit, Austria, 2005

Link

Xbus Kit

Huiyu Zhou and Huosheng Hu

Human Movement Tracking and Stroke Rehabilitation

Technical Report: CSM-420, Department of Computer Sciences, University of Essex, 8 December 2004

Link

MT9

Monaghan C. C, Veltink PH, et al

Control of Triceps Surae Stimulation based on shank orientation using a uniaxial gyroscope

9th Annual Conference of the International FES Society, September 2004

Link

MT9

Galvan-Duque C., Mayagoitia R., Wakil F

Biomechanics of Stair Climbing

RAATE - November 10, 2003 Centre of Rehabilitation Engineering, King's College London, 2003

Link

MT9

Beauregard S

A Helmet-Mounted Pedestrian Dead Reckoning System

IFAWC 2006 March 15-16, Mobile Research Center TZI Technologie-Zentrum Informatik, Universitat Bremen

Link

MTx

Goodvin C. I.

The development of a three-dimensional spinal motion measurement system for clinical practice

University of Victoria Engineering/Computer Science

Link

MT9

Veltink P.H., Hermens H. J., et al

Ambulatory systems for enhanced human motor control

3rd Workshop on European Scientific and Industrial Collaboration (WESIC 2001), SESSION BIO-MECHATRONICS (INVITED SESSION

Link

Veltink P.H., Slycke P. J., et al

Towards automatic optimization of gait supported by a two channel implantable drop foot stimulator

7th Vienna International Workshop on Functional Electrical Stimulation (2001), SESSION DROPPED FOOT, STIMULATORS

Link

Veltink P. H., Luinge H. J., et al

The Artificial Vestibular System - Design of A Tri-Axial Inertial Sensor System and Its Application in the Study of Human Movement

Symposium of the International Society for Postural and Gait Research (ISPG 2001), SESSION PERTURBATIONS OF GAIT AND POSTURE

Link

PhD Thesis, October 2011
VU University, Amsterdam

Link

PhD Thesis, June 2011
Linköping University

Link

PhD Thesis, January 2011
Delft University of Technology

Link

Data Fusion for Ground Target Tracking in GSM Networks

PhD Thesis, December, 2010
University of Siegen, Germany

Link

PhD Thesis, 2010
University of Bologna

Link

PhD Thesis, 2010
University of Bologna

Link

PhD Thesis, June 2010
VU University, Amsterdam

Link

PhD Thesis, October 2009
University of Twente

Link

PhD Thesis, June 2009
University of Twente

Link

PhD Thesis, May 2009
University of Twente

Link

PhD Thesis, May 2009
Technical University Kaiserslautern

Link

PhD Thesis, December 2007 University of Twente

Link

 PhD Thesis, May 2006
University of Twente

Link

PhD Thesis, December 2002
University of Twente

Link

Masters Theses

SmartBot

Develop multi-sensor robot platforms for maritime, agricultural and industry applications.

Date: November 2011 - November 2014

Partners:
Axum Engineering BV
DLV Plant
Imotec
INCAS³
Irmato
Strautmann

Project description
SmartBot is a cross-border collaboration between 24 different partners from Germany and the Netherlands. The aim is to develop multi sensor robot platforms for maritime, agricultural and industry applications. Xsens will participate in two of the three sub projects. The subproject Roboship is about an autonomous intelligent robot for the inspection and repair of ballast water tanks of ships. The sub project Sinbot a pilot environment for intelligent use of industrial robotics in a production environment. The first application will be focused on the production of composite material for the transport sector.
> More about SmartBot

Interaction

Develop an unobtrusive and modular system for monitoring daily life activities and for training upper and lower extremity motor function in stroke.

Date: November 2011 - November 2014

University of Twente
Roessingh Research and Development
University of Pisa
Smartex, Pisa
UZH, University of Zurich

Project description
Continuous daily-life monitoring of the functional activities of stroke survivors in their physical interaction with the environment is essential for optimal guidance of rehabilitation therapy by medical professionals and coaching of the patient. Such performance information cannot be obtained with present monitoring systems. It is the objective of the INTERACTION project to develop and validate an unobtrusive and modular system for monitoring daily life activities and for training of upper and lower extremity motor function in stroke subjects. The system will be unobtrusively integrated in clothing (e-textile), include fabric-based and distributed inertial sensing, and provide telemonitoring and adaptive on-body feedback capabilities. Telesupervision facilities will enable a clinical expert at a distance to evaluate performance effectively, coach the patient and influence training. Monitoring will be based on ambulatory sensing of muscle activation (EMG), interaction forces and body movements. The physical interaction with the environment during reaching and grasping will be assessed by relating interaction forces and movements. This provides information about power exchange between the human body and the environment, dynamics of the environment and task performance. Balancing the body will be assessed from ground reaction forces and relative foot placements. EMG provides information about neural control of movements, including abnormal synergies and spasticity. The assessment is made context aware by task identification and estimation of the dynamics of the environment from the sensed quantities. The system will first be validated in a lab setting, comparing the system against current clinical measures. It will subsequently be demonstrated during the actual daily life of stroke survivors.

Fusion

Development of ‘Click-On-and-Play’ 3D ambulatory motion monitoring and feedback.

Date: 2008 - now

Partners:
Roessingh Research and Development
University of Twente
TU Delft
Groot Klimmendaal
Sint Maartenskliniek

Project description
The FUSION project is a follow up of the successful project FreeMotion. A consortium of Dutch research institutes and companies, including Xsens have teamed up to develop a fast, instant manner of monitoring motion, using inertial sensor technology, with the added potential of real-time feedback. The goal of the research is to facilitate users with no prior knowledge of specialised hardware and software programming, such as physiotherapists, rehabilitation doctors etc.
> More about Fusion

muFly

Fully Autonomous Micro-Helicopter

Date: July 2006 - July 2009

Partners:
Autonomous Systems Lab of ETH Zurich
University of Freiburg (Albert-Ludwigs-Universität Freiburg)
Cedrat & Cedrat Technologies
CSEM (Centre Suisse d'Electronique et de Microtechnique SA)
Berlin University of Technology

Project description
Autonomous micro flying robots combine a large variety of technological challenges and are therefore an excellent showcase for leading edge micro/nano technologies and their integration with information technology towards a fully operational intelligent micro-system. Therefore, the muFly project proposes the development and implementation of the first fully autonomous micro helicopter comparable in size and weight to a small bird. The key challenges of the project include innovative concepts for power sources, sensors, actuators, navigation and helicopter design and their integration into a very compact system. The envisaged fully autonomous micro-helicopter will weight less than 30g and measure only 10cm in diameter. MuFly is a STREP project under the Sixth Framework Programme of the European Commission.
> More about muFly

Freemotion

The FreeMotion consortium

Date: January 2005 - December 2008

Partners:
Roessingh Research and Development (RRD
BMTI Twente University
Faculty of Movement Sciences, Free University of Amsterdam
Biorobotics Laboratory, Delft Technical University
Department of rehabilitation of Free University Medical Center, Amsterdam
Re-lion
Noldus Information Technologies
TNO Industries

Project description
FreeMotion is conducted by a consortium of Dutch research institutes and companies, in wich Xsens also participates. Currently optimal decision making around motor disorders and performance can only be made applying accurate and complete motion analysis methods. These elaborate laboratory based methods are only available in a few elite institutes.

FreeMotion focusses on the development of ambulatory methods using only body worn sensors for motion analysis in order to provide a larger part of the healthcare, ergonomic and sports professionals with similarly optimal decision making tools. Read more about Motion Capturing, Gait Analyses & Biomedical signals and systems.
> More about Freemotion

Matris

Markerless real-time Tracking for Augmented Reality Image Synthesis

Date: February 2004 - January 2007

Partners:
Fraunhofer Institute for Computer Graphics
BBC R&D
Christian-Albrechts-University Kiel
University of Linkoping

Project description
Xsens teams up in a strong European consortium to develop a unique, markerless, solution for real-time 6DOF tracking for augmented and mixed reality applications. Per Slycke (CTO) of Xsens: "The MATRIS project aims to develop a unique, easy-to-use and robust technology for accurate 6DOF tracking of cameras in augmented and mixed reality applications. In technical terms, the system will track position, orientation, and focal length of a camera in real-time, using the camera images together with unobtrusive 6DOF inertial motion sensors mounted on the camera. This approach mimics the way a human orients himself, using the vestibular organ (in the ears) -which is essentially an inertial measurement unit, and the eyes- essentially comparable to a camera. The great thing about this approach is that the tracking system will not require any special infrastructure, or markers, to be installed."

TUBA

Transceiver and Inertial Unit for Biomedical Application

Date: January 2002 - January 2005

Partners:
European technology for business limited
The salisbury health care national health service trust
Roessingh research and development b.v.
University college cork - national university of ireland

Project description
Xsens participated on this project, which was funded under the European Union 5th Framework Programme. The project developed a device to help patients with a problem known as drop foot. The device consists of a medical implant for stimulation of the peroneal nerve and a stimulator that strapped to the lower leg. Instead of using manual switches or footswitches for control of the stimulator, data of inertial sensors are used. A software algorithm accurately detects the gait phase and ensures that the implant stimulation is triggered at the correct time instance.

There are currently around 1.4 M stroke patients living with drop foot in Europe and the USA. In addition, the 3 different Microsystems to be developed can be used in a variety of other medical applications, e.g. other implantable systems and in monitoring human movement to help prevent back injury. This project introduces new Microsystems into the market place, thus helping to reduce the material resources required. In addition, it will improve the health and quality of life for people suffering from walking disabilities.

Impulse

Improved Mobility through imPlanted fUnctional eLectricalStimulation of nErves

Date: June 2000 - May 2002

Partners:
Finetech-Medical Ltd
Roessingh Research and Development

Project description
The purpose of this project is to investigate the safety and effective of an Implanted Dropped Foot Stimulator. This medical device is a 2 channel implanted neuromuscular stimulator intended for the correction of dropped foot following stroke.

The nerve that controls the lifting of the foot in walking is called the common peroneal nerve. At a point, just below the knee, this nerve splits into two branches, the deep branch and the superficial branch. The deep branch goes to the muscles that lift (dorsiflex) and turn inward (inversion) the foot while the superficial branch supplies the muscles that turn the foot outwards (eversion). In normal walking, a combination of these movements is required. Therefore an electrode is surgically inserted in both nerves enabling the movements to be controlled separately. This causes nerve impulses to travel down the nerve to the muscle in the same way as naturally occurring nerve impulses. Stimulation begins when the foot is lifted and ends when the heel is returned to the ground. Sensation from the electrical stimulation should be very slight and it is expected that users will quickly become accustomed to it. Once healing has occurred the operation site scars should be negligible. It may be possible to palpate the implant under the skin but it is not expected to be noticeable to the eye.