Tony Monnet

Université de Poitiers | UP · Institut de recherche de Poitiers : Recherche ingénierie en matériaux, mécanique et énergétique pour les transports, l'énergie et l'environnement (Institut Pprime)

Although lots of assistive devices have been studied to fight against caregivers' work-related musculoskeletal disorders, stand-and-turn devices effects on biomechanical constraints are still unknown. The aim of this study is to provide and compare quantitative data on loads in the low back area resulting from the use of a motorless stand-and-turn...

Traditionally, motion analysis in clinical laboratories using optoelectronic systems (MOCAP) is performed in acquisition volumes of limited size. Given the complexity and cost of MOCAP in larger volumes, action sports cameras (ASC) represent an alternative approach in which the cameras move along with the subject during the movement task. Thus, thi...

The thumb’s use is associated with musculoskeletal disorders in many sectors. It plays an essential role in the fulfillment of tasks such as holding. Unlike other upper limb joints, there are insufficient data on comfort angles of the thumb. The purpose of this study was to investigate the thumb joint angles for five order pickers with different an...

Magneto-inertial measurement units (MIMUs) are a promising way to perform human motion analysis outside the laboratory. To do so, in the literature, orientation provided by an MIMU is used to deduce body segment orientation. This is generally achieved by means of a Kalman filter that fuses acceleration, angular velocity, and magnetic field measures...

The aim of this study was to assess the precision and accuracy of an Action Sport Camera (ASC) system (4 GoPro Hero3+ Black) by comparison with a commercial motion capture (MOCAP) system (4 ViconMX40). Both systems were calibrated using the MOCAP protocol and the 3D markers coordinates of a T-shaped tool were reconstructed, concurrently. The 3D pre...

Tethered swimming is a method often used to measure or enhance the physical and technical resources of swimmers. Although it is highlighted that the technique used in tethered swimming is probably different from that used in free conditions, there are few comparative studies on this subject. The current study aims to compare fully tethered and free...

Gyroscopes are now becoming one of the most sold MEMS sensors, given that the many applications that require their use are booming. In the medical field, gyroscopes can be found in Inertial Measurement Units used for the development of clinical tools that are dedicated to human-movement monitoring. However, MEMS gyroscopes are known to suffer from...

The propulsive forces generated by the hands and arms of swimmers have so far been determined essentially by quasi-steady approaches. This study aims to quantify the temporal dependence of the hydrodynamic forces for a simple translation movement: an impulsive start from rest. The study, carried out in unsteady numerical simulation, couples the cal...

This computational study has highlighted the role of the delayed stall effect in the generation of unsteady swimming forces. These force coefficients are almost twice higher to those obtained in quasi-steady configurations. The LEV benefits both the drag and lift components, at a different angles of attack. Although the motion of this simulation is...

Competitive swimming; unsteady flow; computational fluid dynamics; drag and lift coefficients

The development of codes and power calculations currently allows the simulation of increasingly complex flows, especially in the turbulent regime. Swimming research should benefit from these technological advances to try to better understand the dynamic mechanisms involved in swimming. An unsteady Computational Fluid Dynamics (CFD) study is conduct...

The effect of wobbling mass modeling on joint efforts estimation has mainly been assessed using computer simulation. The main challenge of an experimental approach for calculating joint efforts is to distinguish bone to wobbling mass inertial parameters and kinematics. Our objective was to experimentally assess the wobbling mass effect on jump dyna...

In the fields of medicine and biomechanics, MEMS accelerometers are increasingly used to perform activity recognition by directly measuring acceleration; to calculate speed and position by numerical integration of the signal; or to estimate the orientation of body parts in combination with gyroscopes. For some of these applications, a highly accura...

Identification of human body segment inertial parameters is usefull to compute accurate inverse dynamics for biomechanic studies like gait analysis or to have a realistic muskulo-skeletal model. The purpose of this study is to propose an identification method to compute the ten inertial parameters of a segment (mass, localisation of center of mass...

The aim of this study was to investigate the evolution of kinematic hand parameters (sweepback angle, angle of attack, velocity, acceleration and orientation of the hand relative to the absolute coordinate system) throughout an aquatic stroke and to study the possible modifications caused by a variation of the swimming pace. Seventeen competitive s...

Computer simulation models have shown that wobbling mass on the lower limb affects the joint kinetics. Our objective was to propose a non-invasive method to estimate bones and wobbling mass kinematics in the lower limb during hopping. The chain kinematic model has set degrees of freedom at the joints and free wobbling bodies. By comparison to a mod...

The hydrodynamic parameters of the hand (Angle of attack, sweepback, velocity and orientation) play an important role in the generation of the resultant forces. These parameters were measured throughout an aquatic stroke to study the possible modifications caused by a variation of the swimming pace. Seventeen competitive swimmers swam at the long d...

The aim of this study was to determine the role played by the entry-and-stretch phase in the coordination of swimming, at the different paces of race. Three national level swimmers (two men and one woman) were recorded, in lateral and bottom views, in three swimming paces: sprint (50 m and 100 m), middle-distance (200 m and 400 m) and long-distance...

La modélisation et l'optimisation en natation La modélisation peut être définie comme une représentation simplifiée d'une réalité complexe : la natation sportive. Celle-ci peut se définir comme une activité physique qui vise l'atteinte d'une haute performance dans un milieu aquatique réglementé. Il est possible de la décomposer en deux phases: nagé...

The measure of human movement develops in numerous domains such as ergonomics, to prevent for example the musculoskeletal disorders, the physical medicine, to evaluate post operative rehabilitation or the rehabilitation of elderly after a fall, or even sports for performance improvements of athletes. The measure of movement is then essential to est...

The purpose of this study was to investigate the sliding characteristics of a new shoe (NSh) concept. The NSh has been developed with the specific aim of facilitating sliding on hard surface such as tennis players can do on clay or synthetic turf. Five young tennis players performed several trials on a walkway instrumented with seven force platform...

The flow generated by the swimmers has an unsteady vortex dynamic. The quasi-steady approach is, in this context, inappropriate for a comprehensive analysis so an unsteady simulation is required (Sato & Hino, 2003). A URANS (Unsteady Reynolds Averaged Navier- Stokes) computational study with a free surface, which uses the moving mesh method, is pro...

The purpose of this study was to evaluate a new procedure of data processing from a body-mounted accelerometer to improve the assessment of vertical jump height. As the main difficulty when using an accelerometer is to detect the times of take-off and of landing, a new criterion was proposed to detect these times more accurately. Thirty physical ed...

Current trends in swimming biomechanics are focused on accurate measurements. Nowadays, reliable calibration methods have been proposed to reach an accuracy of about 1 mm on rigid structure. But the question remains about the final accuracy for three-dimensional hand kinematics measurement during the underwater phase of front crawl swimming. Furthe...

La mesure du mouvement humain se développe dans de nombreux domaines tels que l’ergonomie, pour prévenir, par exemple, les troubles musculo-squelettiques, la médecine physique pour, en particulier, évaluer le reconditionnement post chute des personnes âgées ou la rééducation post opératoire, ou encore le sport à des fins d’amélioration des performa...

El estudio biomecánico de la carrera a pie ha sido objeto de numerosos trabajos de investigación. Para que éstos sean eficaces, deben emplearse instrumentos de observación y medición cada vez más perfeccionados. El movimiento se evalúa en los tres ejes del espacio con recursos técnicos que incluyen sistemas de análisis de imágenes para la medición...

Due to marker-specific soft tissue artefacts, the choice of the markers defining the segment-embedded frame affects the functional joint centre location, with subsequent error propagation to joint kinematics and kinetics in gait analysis. Our aim was to assess the effect of the number and placement of markers on the precision of the hip joint centr...

L'étude biomécanique de la course à pied fait toujours l'objet de nombreux travaux de recherche ; ces derniers, pour être performants supposent l'utilisation d'outils techniques d'observation et de mesures de plus en plus perfectionnés. Le mouvement est alors évalué suivant les trois axes de l'espace à l'aide de plateaux techniques qui regroupent d...

Problems of posture in cycling are closely related to a badly adjusted saddle. Many of these problems can be prevented if the bicycle is correctly adjusted. In the search for an optimum posture of the cyclist, a balance should be found to both prevent injuries and enhance performance. If the influence of bicycle ‘posture height’ on generation of mu...

The aim of this paper is to analyse the repeatability of marker deformation and marker ranking across subjects and motor tasks. A method based on the solidification of the thigh with optimized rototranslation was applied which used 26 markers placed on the left thigh. During five trials of landing and five trials of walking for eight participants,...

Kinematics of skin markers are affected by skin tissue artefact with respect to the bone during sports activities or locomotion. The purpose of this study is to determine the less disturbed marker’s location for walking and landing. Twenty-six markers were put on the thigh of nine male subjects. Each subject performed a static trial, a setup moveme...

Usually, biomechanical models used for human motion analysis are oversimpli- fied, especially for clinical analyses (e.g. Helen Hayes model). The calculated net joint forces and torques are sensitive to the input data: segment kinematics and body segment inertial parameters. It is therefore necessary to improve these input data us- ing new methods...

A rolling motion analysis system has been purpose-built to acquire an accurate three-dimensional kinematics of human motion with large displacement. Using this device, the kinematics is collected in a local frame associated with the rolling motion analysis system. The purpose of this paper is to express the local kinematics of a subject walking on...

The motion equations of a rigid body involve ten inertial characteristics: the mass, the mass center position and the inertia matrix. In order to identify these ten inertia characteristics, we propose an approach unifying them in a 4 × 4 positive definite symmetric matrix. The translation vector and the rotation matrix of the rigid body are also ga...

A special antisymmetric 4 × 4 matrix form of the equation of motion of a rigid body is proposed. This form depends linearly on the symmetric (4 × 4)-matrix of the Fayet global inertia tensor, containing the ten inertia parameters of a rigid body (the mass, the three coordinates of the centre of mass and the six components of the classical inertia t...

In this work, an identification method is presented for the determination of the body segment parameters. The identification consists in writing the reaction model: the 6 components of the interaction between the multibody system and outside are put in relation with the segments kinematic. The equations of motion are written in matrix form. The 6 c...

Cet article présente une formulation matricielle des équations du mouvement d'un système composé de n corps. Les paramètres inertiels de tous les segments du système multi-corps sont contenus dans une matrice (3n+1)×(3n+1) symétrique et positive. Cette matrice est constante et apparaît linéairement dans les équations du mouvement. Ainsi, avec cette...

This paper presents two methods for human body modelisation: the location of the joint centre and the identification of the body segment inertial parameters. These methods require only tools usually used in biomechanics (force plate and motion analysis system) and allow to have precise and personal parameters.

Determination of the hip joint centre (HJC) using a functional approach requires access to the kinematics of various body postures. The present study aimed to determine the combined impact of the nature of the movement, its type and the number of cycles, on the accuracy of HJC estimation. Kinematics noise was modelled based on the deformation of hi...

A recent paper has described a new functional method, the symmetrical centre of rotation (SCoRE), for locating joint centre position [Ehrig, R.M., Taylor, W.R., Duda, G.N., Heller, M.O., 2006. A survey of formal methods for determining the centre of rotation of ball joints. Journal of Biomechanics 39 (15), 2798-2809]. For in vitro analyses, the SCo...

The parallel between trainers and specialists of athletic movements mechanical analysis is an essential step to improve elite athletes performances. Thus, the Centre d'Analyse d'Image et Performance Sportive Poitou- Charentes (CAIPS) was set up to enlarge exchanges and to make them bidirectional. Providing trainers observations with the measure, th...

The motion equations of a rigid body involves ten inertial characteristics which appear linearly: the mass, the mass center position (3 components) and the inertia matrix (6 independent components) In order to identify the ten inertial characteristics, most authors propose me- thods based on Newton-Euler formalism in which a 10 ◊ 1 vector has to be...

La détermination des paramètres inertiels des différents segments constituants le corps humain est un problème récurrent et très actuel de la biomécanique. Les méthodes classiques déterminent ces paramètres par des équations de régression (modèles de Zatsiorsky, Dempster...) ou en modélisant les segments par des formes géométriques simples (modèles...