Virtual Wall

A simulated physical boundary in a haptic interface that the user can feel through a force-feedback device, modelled as a massless plate backed by a spring with stiffness and a damper with viscosity. Virtual walls are used to represent the edges and boundaries of graphical user interface elements — such as window borders, menu edges, or button outlines — allowing blind users to perceive the spatial layout of a GUI through touch. When a user's haptic device reaches a virtual wall, they feel resistance that prevents or discourages further movement in that direction, similar to running a finger along the edge of a physical object. The stiffness, damping, and friction properties of virtual walls can be adjusted to convey different types of boundaries.