Patent ID: 8239145

Claim:
A force feedback method, comprising: placing a receiver at a predetermined height above a plurality of nozzles arranged on a plane, the receiver including a concave center unit that declines radially outward from an axis of symmetry of the receiver to an outer border of the concave center unit, such that a shape of the concave center unit is a hemisphere, and an inclined side surface unit that inclines radially outward from the outer border of the concave center unit with respect to the axis of symmetry, selecting a nozzle for which |V PN | is the smallest from among candidate nozzles on the plane that satisfy R 1 ≦|V PN |≦R 2 and 0≦|θ ij |≦γ, wherein |V PN | indicates a distance between a candidate nozzle and the axis of symmetry of the receiver, R 1 indicates a distance between the axis of symmetry of the receiver and an inner border of the inclined side surface unit, R 2 indicates a distance between the axis of symmetry of the receiver and an outer border of the inclined side surface unit, |θ ij | indicates an absolute value of an angle between a first direction from the candidate nozzle to the axis of symmetry of the receiver and a second direction of a force to be provided to the receiver, and γ indicates a predetermined value for the angle, and jetting a gas or a liquid from the selected nozzle upon the inclined side surface unit of the receiver to convey a force in a direction perpendicular to a direction of the jetting gas or liquid toward the axis of symmetry of the receiver.