Microsoft has applied for a patent for a novel type of body suit to improve immersion in VR sessions.
Described as a Flexible Magnetic Actuator, the device would use two layers of flexible magnets (for example magnets woven into cloth) where the attraction can be changed dynamically between the layers (e.g. via an electromagnet) allowing a controller to selectively increase or decrease the friction between layers and even lock the two layers in place.
Microsoft envisions using the actuators over joints, such as your elbow and finger, which would allow users to have their real-world movement restricted when they touch or otherwise encounter virtual objects.
The patent was applied for in June 2017 and published today. It can be seen in full here.