Walking is one of the most important and most automated human movements. Contrary to what one might think, walking is a very complex cyclic mechanism which allows the study to develop new technologies in the fields of medicine and robotics for example. Walking in line with a laminar headwind disrupts human locomotion; that is the problematic being studied in this research project with a wind tunnel.

View of the built platform and the AMTI torque force platform

We wished to understand how do react the lower limb joints when you get a more or less significant headwind during walking and what are the impacts on the articular powers in the lower limbs. The purpose of this project is to design a walking corridor suitable for a wind tunnel in order to achieve walking tests with a front laminar wind.

View of the ETS Larcase wind tunnel output window

WIND TUNNEL USE

The idea is to have someone walk on a straight line in this corridor quite naturally and disturb his movement with a laminar  headwind created by the wind tunnel. The tests were conducted with wind speeds from 5 m/s (18 km/h) to 22m/s (79 km/h).

Other view of the platform in relation with the Vicon 3D optoelectronic motion capture system

We have designed a walking corridor containing a torque force platform (AMTI), to measure moments and ground reaction forces during walking. In addition to the torque force platform, a 3D optoelectronic motion capture system (VICON) was used in order to measure the person’s kinematics while walking. We then estimate the required muscle’s forces and moments developed in the ankle, knee and hip using inverse dynamics method and a formalism based on quaternions.

View of the walking corridor, a component of the Vicon 3D optoelectronic motion capture system and the AMTI torque force platform

WIND TUNNEL’S WALKING CORRIDOR

The walking corridor should be long enough so that the subject is able to walk at least three steps before setting foot on the torque force platform. We had to raise the walking corridor ta have the person’s center of gravity in the middle of the wind tunnel output window. Finally, we have fit the torque force platform in the walking corridor just before the wind tunnel output window.

The project was made possible through collaboration between LIO and LARCASE laboratories at ETS under the supervision of professors Rachid Aissaoui (from the Lio laboratory) and Ruxandra Botez (from the LARCASE laboratory).