Since 2017, the biomechanics and impact mechanics laboratory (LBMC) has had a multi-adjustable experimental seat to study seating comfort. Designed and manufactured according to specifications defined by the laboratory, this experimental seat makes it possible to simulate a wide range of seats used for land and air transport thanks to its motorized adjustments. This facility allows the experimenter to carry out a parametric study on the geometric dimensions of a seat and to understand the role of the contact force, particularly shear forces. Equipped with force and positioning sensors, all contact forces and seat geometry can be measured. More specifically, it is equipped on the seat with a matrix of 52 cylinders, each adjustable in height and each equipped with a three-axis force sensor. These cylinders make it possible to vary the seating surface and measure the distribution of contact forces in the three directions.

More recently, a matrix of 263 hydraulic cylinders was manufactured to simulate the surface of a seat back. Similar to the operation of the seat cylinders, each backrest cylinder is equipped with a force sensor and is adjustable in position using a pumping system.
The device has two control interfaces, one for the experimenter and the other for the person participating in an experiment. We can easily impose a same test configuration on all participants. A participant has the possibility to adjust the dimensions authorized by the experimenter via a tablet in order to obtain their preferred configuration.
With the measurements provided by the experimental seat as input, the biomechanical parameters necessary to understand the perceived discomfort can be estimated using the customizable biomechanical models developed by the LBMC.

A video showing how the reconfigurable seat works is available:
https://www.youtube.com/watch?v=2JQTTM1PWS0