Sensor Shorts version 1

Reducing hamstring injuries in football and field hockey

In this version of the sensor shorts we integrate five acceleration sensors (MPU-9250 IMUs, InvenSense Inc.) in a stretchable legging. The sensors are much smaller and lighter than the Shimmer IMU sensors used for the version 0 and are therefore expected to be more comfortable and result in less spurious signals due to the inertia of the sensors itself.

Design and the application of the wave pattern of the lead wires on the textile
The encapsulated sensor
Top view of a MPU- 9250 IMU
Electronics placed in a waist pack

Results and conclusions

In order to test the accuracy of the new sensor shorts the recorded movements were compared to an Optoelectronic Motion Analysis System (Vicon Nexus), see Fig.4. From this we conclude that our measurement system was able to measure the local knee and hip angle movements as accurate as the Vicon system, which is currently considered as the golden standard for local motion measurements.

Graduate student

  • Suman Vinasithamby (3mE)

Supervision

Knee- and hip joint angles (in degrees) obtained from the Smart Sensor Shorts in dashed grey and from the Optoelectronic Motion Analysis System (VICON Nexus) in solid black during a 10m sprinting, kicking and jumping movement of one subject. In the plot, sprint 1 stands for jog, sprint 2 for a maximal sprint, kick 1 for a pass, kick 2 for a shot, jump 1 for a jump from standstill and jump 2 for a jump with run-up.

Video of sensor signals during a short run and pass

Camera team of Sportlab Sedoc in the lab
Gregory Sedoc with the sensor shorts