The virtual reality system is designed to be cost-effective, scalable, and provide high resolution with an “intelligent carpet” touch sensor.
Limited physical spaces in modern, urban life pose locomotion challenges. Virtual reality (VR) translates such constrained real spaces to larger, virtual spaces using efficient locomotion systems. However, current VR locomotion systems can be uncomfortable and raise privacy concerns. In response to these issues, researchers from Gwangju Institute of Science and Technology, Korea and MIT CSAIL have now developed “Seamless-walk,” a foot-based VR locomotion system that offers a natural and comfortable experience for applications in VR gaming and healthcare, including gait analysis in physical therapy.
In their recent article published online in the journal Virtual Reality, the researchers, led by Dr Kyung-Joong Kim, associate professor at GIST, have detailed the development of the VR locomotion system.
“When we started collaborating with MIT, they introduced an interesting new sensor called the ‘intelligent carpet.’ In our view, it was a great opportunity as well as a challenge for us since it had not been developed for any specific application. Therefore, we wanted to make something practical and interesting with this sensor and our AI technology,” explains Kim. “Accordingly, we decided to develop a VR game controller with the ‘intelligent carpet’ sensor that would be useful in VR gaming.”
Seamless-walk works like this: The intelligent carpet captures high-resolution foot pressure imprints in real time as the user moves around by measuring the applied pressure through resistance changes. The footprint information is then fed into a machine learning model that extracts the strong pressure points using a technique called “K-means clustering.” In this method, the pressure points are divided into two clusters, corresponding to the user’s left and right feet. From these clusters, the user’s body direction and foot intervals are then extracted to estimate the angle and movement speed.
Moreover, Seamless-walk has a modular structure that enables a scalable and inexpensive installation of a touch sensing platform. The team conducted tests on 80 individuals using Seamless-walk in a 3D virtual world exploration game, demonstrating that the novel technology of the system provides an immersive, natural, and comfortable experience. At the same time, it does not compromise the overall VR experience, outperforming existing VR locomotion methods, according to the researchers.
“In the future, we plan to add more detailed gait analysis functions to the current system. This would enhance our sensor and gait analysis system to provide fall detection and health monitoring in a comfortable manner without any privacy issues,” highlights Kim. “This method could also be used at the gym for monitoring the gait of users on the treadmill or checking their balance during weight training.”
Taken together, this novel development has the potential to advance virtual reality gait analysis in physical therapy.
Infographic Credit: Kyung-Joong Kim from Gwangju Institute of Science and Technology