Techniques for Multiple Room Connection in Virtual Reality: Walking Within Small Physical Spaces

In Virtual Reality (VR), navigating small physical spaces often relies on handheld controllers, such as teleportation and joystick movements, due to the limited space for natural walking. However, walking-based techniques can enhance immersion by enabling more natural movement. This paper presents three room-connection techniques - portals, corridors, and central hubs - that can be used in virtual environments (VEs) to create "impossible spaces". These spaces use overlapping areas to maximize available physical space, promising for walking even in constrained spaces. We conducted a user study with 33 participants to assess the effectiveness of these techniques within a small physical area (2.5 x 2.5 m). The results show that all three techniques are viable for connecting rooms in VR, each offering distinct characteristics. Each method positively impacts presence, cybersickness, spatial awareness, orientation, and overall user experience. Specifically, portals offer a flexible and straightforward solution, corridors provide a seamless and natural transition between spaces, and central hubs simplify navigation. The primary contribution of this work is demonstrating how these room-connection techniques can be applied to dynamically adapt VEs to fit small, uncluttered physical spaces, such as those commonly available to VR users at home. Applications such as virtual museum tours, training simulations, and emergency preparedness exercises can greatly benefit from these methods, providing users with a more natural and engaging experience, even within the limited space typical in home settings.