Abstract: A haptic feedback device for virtual objects includes a head-mounted display unit, an HMD control unit, a haptic feedback unit, and a haptic information DB for storing haptic information in association with each type of virtual object. The HMD control unit includes a display controller that causes a virtual object and a user focus to appear on a display, and a haptic information transmitter that reads, when the user focus is placed over a selectable virtual object, haptic information associated with the type of the selected virtual object from the haptic information DB, and transmits the haptic information to the haptic feedback unit. The haptic feedback unit includes a movable portion movable with a user operation, a movement resistance generator that applies movement resistance to the movable portion, and a power feed controller (movement resistance controller).

Abstract: haptic feedback device for virtual objects includes a head-mounted display unit, an HIVID control unit, a haptic feedback unit-4, and a haptic information DB for storing haptic information in association with each type of virtual object. The HMD control unit includes a display controller that causes a virtual object and a user focus to appear on a display, and a haptic information transmitter that reads, when the user focus is placed over a selectable virtual object, haptic information associated with the type of the selected virtual object from the haptic information DB, and transmits the haptic information to the haptic feedback unit. The haptic feedback unit includes a movable portion movable with a user operation, a movement resistance generator that applies movement resistance to the movable portion, and a power feed controller (movement resistance controller).

Abstract: Disclosed is a magnetorheological fluid including a fine particle mixture and a dispersion medium. The fine particle mixture includes first particles, second particles, and third particles. The first particles are magnetic particles having an average particle size greater than or equal to 1 ?m and less than or equal to 30 ?m. The second particles are magnetic particles having an average particle size greater than or equal to 100 nm and less than or equal to 300 nm. The third particles are particles having an average particle size greater than or equal to 10 nm and less than or equal to 50 nm. A proportion of the first particles in the fine particle mixture is greater than or equal to 60 mass % and less than 99 mass %, the remainder being the second particles and the third particles.

Abstract: A magneto-rheological fluid includes: a magnetic particle mixture; and a dispersion medium in which the magnetic particle mixture is dispersed. The magnetic particle mixture includes first magnetic particles and second magnetic particles. The first magnetic particles have an average particle size greater than or equal to 1 ?m and less than or equal to 50 ?m. The second magnetic particles have an average particle size greater than or equal to 20 nm and less than or equal to 200 nm, and have surfaces provided with a surface modified layer. A proportion of the second magnetic particles in the magnetic particle mixture is greater than or equal to 2 wt % and less than or equal to 10 wt %.

Abstract: A magneto-rheological fluid includes: a magnetic particle mixture; and a dispersion medium in which the magnetic particle mixture is dispersed. The magnetic particle mixture includes first magnetic particles and second magnetic particles. The first magnetic particles have an average particle size greater than or equal to 1 ?m and less than or equal to 50 ?m. The second magnetic particles have an average particle size greater than or equal to 20 nm and less than or equal to 200 nm, and have surfaces provided with a surface modified layer. A proportion of the second magnetic particles in the magnetic particle mixture is greater than or equal to 2 wt % and less than or equal to 10 wt %.