Improving the comfort and accessibility of transport vehicles

Science topics February 2015 Road safetyHuman behaviourModelling and computer simulation

Xuguang Wang, Senior researcher - TS2 Department , LMBC Laboratory

Updated on 09/18/2017,

The « Biomechanics¹ for ergonomic² simulation » team at the LBMC³ is developing tools and techniques for observing, understanding, evaluating and simulating human motor activity. The team focuses on motor activity during the use of transport facilities and vehicles with a view to improving user comfort and accessibility.

Numerical dummy models, which are a computerised model of a human, are one of the simulation tools and are becoming essential in order to evaluate the ergonomics of a product or a workstation. Evaluation of this type can contribute to the design phase, simplifying the production cycle in order to improve industrial competitiveness.


Considering ergonomics within vehicles


Today’s numerical dummy models for ergonomic simulation are based on a three-dimensional geometrical model of the external surface of the body and a simplified representation of the internal skeleton. Starting at the end of the 1980s the LBMC, in collaboration with the motor vehicle manufacturer Renault, developed one of the first European numerical dummy models, Man3D. Since then, the laboratory has been involved in bilateral collaborative projects with motor vehicle manufacturers (PSA, Renault Trucks, and more recently Toyota Motor Europe and Ford). In this connection, the LBMC has been a major player in two large-scale European projects on human digital modelling (REALMAN, 2001-2004 ; DHErgo, 2008-2011, which it coordinated). 

An example of MAN 3D for designing the driving position



The ability to predict movement and discomfort

In addition, a new methodology has been developed to simulate movement and evaluate the resulting discomfort. At the request of Renault, this innovative methodology has been implemented in a software package known as RPx4. A large database of movements has been created, ranging from a simple movement to press a button on the dashboard to vehicle ingress/egress movements.

Simulation performed by the RPx software package.

(a) Simulation of several reach envelopes

(b) Simulation of vehicle ingress/egress movement with the volume swept by a body segment.






More recently, the human digital model has acquired muscles, in particular in its legs. This means it can now measure muscular effort such as that involved in declutching. Other models are currently being developed which perform more precise simulation of interaction between the human being and the environment (e.g. buttock/seat interface).


Musculoskeletal model of the leg developed by the LBMC

to estimate the muscular effort required during declutching





Parametric modeling of human body and seating discomfort

How to take into account the variability in human body dimensions is one of the questions posed when designing a product like an automobive or airplane seat. LBMC has developed a parametric surface model of the buttock-thigh complex recently in collaboration with Zodiac Seat France, leader of the airplane seats. In parallel, LBMC is working on seating discomfort criterion in a national collaborative project supported by DGAC5, which is aimed to develop more comfortable, accessible and ecological airplane seats in the future. A new unique experimental seat was built for experimentally investigating sitting biomechanics.






Parametric surafce model of the buttock thigh complex

with stature, weight and thigh flexion angle as predictors






1 « Biomechanics is the study of the structure and function of biological systems […] by means of the methods of mechanics » Wikipedia definition 

2 « Ergonomics is the practice of designing products, systems, or processes to take proper account of the interaction between them and the people who use them » Wikipedia definition

3 Laboratory of Impact Mechanics and Biomechanics is a research unit that is jointly managed by IFSTTAR and Université Claude Bernard

4 Realman Program eXtension, extends the European REALMAN project and sets out to develop software which would enable Renault engineers to integrate motion simulation in the car design process.

5 Directorate General of Civil Aviation, project n ° 2014 930818.




Find out more ...

  • Beurier, Georges, Michelle Cardoso, and Xuguang Wang. “A New Multi-Adjustable Experimental Seat for Investigating Biomechanical Factors of Sitting Discomfort.” SAE Technical Paper, 2017.
  • Bulle J., 2013. Etude expérimentale de la variabilité posturale intra-et inter- individus pour la prédiction de la posture de conduite. Thèse de doctorat Université Claude Bernard Lyon 1, 15 novembre 2013.
  • Causse J., 2011. Analyse cinématique et dynamique du mouvement d’accessibilité à une automobile. Thèse de doctorat Université Claude Bernard Lyon 1, N° d’ordre 117-2011, Soutenu le 20 Juin 2011.
  • Fraysse F., 2009. Estimation des activités musculaires au cours du mouvement en vue d’applications ergonomiques, Thèse de doctorat Université Claude Bernard Lyon 1, N° d’ordre 338-2009, Soutenu le 15 décembre, 2009.
  • Monnier G., Wang X., Trasbot J., (2009) RPx: A motion simulation tool for car interior design. Dans : Handbook of Digital Human Modeling: Research for Applied Ergonomics and Human Factors Engineering, ed. Vincent G. Duffy. CRC press Taylor and Francis Group.
  • Romain Pannetier, 2012. Développement des modèles biomécaniques de l’humain pour l’évaluation ergonomique de commandes automobiles – Application à la pédale d’embrayage, Thèse de doctorat Université Claude Bernard Lyon 1, N° d’ordre 214 - 2012, Soutenu le 09 Novembre 2012.
  • Savonnet L. Duprey S., Cardoso M.,Wang X. A parametric model of the thigh-buttock complex for developing FE model to estimate seat pressure. 5th International Digital Human Modeling Symposium, June 26-28, 1017, Bonn, Germany.
  • Wang X., Barelle C., Pannetier R., Numa J. 2009. Capacité musculaire des membres inférieur et supérieur appliquée aux commandes automobiles et leur perception d’effort. Contrat Renault F08-22. 49p.
  • Wang X., Trabot J. (2011) Effects of target location, stature and hand grip type on in-vehicle reach discomfort. Ergonomics 54(5), 455-476.