VR – Movement analysis – Volfon

Measurement of the trajectories of the hand
Trajectories of the right wrist (green, yellow) and left wrist (blue, black) when exploring the human reachable volume.


As part of a cutting-edge research project in the field of measurement and analysis of human mobility the tools for the instrumented evaluation of the reachable space were designed and assembled. They were then tested on a group of patients in a partner clinic (CHUV). These tools combine several cutting edge techniques such as the laser-based movement tracking technology “Lighthouse”, adapted into a tool for rapid and completely automated measurement of upper limb motions; as well as 3D geometric analysis techniques to convert these measurements into a volumetric assessment of space. Within the framework of this project, in addition to the analysis of complex movements in 3D, the use of “games” in virtual reality made it possible to help the patients to relax, while guiding them in a precise and repeatable way through their exercises. This guidance was possible thanks to the HTC Vive virtual reality headset and a custom-made Unity software created for this project.

In accordance with the good practices used in research, the records were then subjected to a statistical analysis and compared to a group of healthy subjects.

Motion measurement and patient guidance system
Motion measurement and patient guidance system

10 healthy subjects were tested in the laboratory. 16 patients presenting different pathologies limiting the mobility of the shoulder, were then tested directly in the consultation box of their attending physician.

The recorded data made it possible to show that this new test tool is suitable for use on patients within the hospital’s walls. The repeatability of the test was also assessed, indicating excellent results for the patients (ICC = 0.91). In addition, the validity of the test was assessed by comparison with numerical simulations under controlled conditions, as well as by comparison with similar projects conducted by other research laboratories, showing that the current measurements corresponded well to the expected values. Finally, several other metrics were calculated on the basis of these records for a more in-depth analysis of the patients’ pathology.

E reachable volumes
The volume in green represents the volume reachable by the right hand, while the red volume represents the volume reachable by the left hand. The black dots represent the positions recorded or interpolated during the measurements. The left and right columns compare the results of the same patient, measured twice, seen from several angles …

Project carried out for the Ecole Polytechnique Fédérale de Lausanne (EPFL) and the Center Hospitalier Universitaire Vaudoise (CHUV).