Haptic input devices

• US 7,499,021 B2
• Filed: 10/29/2001
• Issued: 03/03/2009
• Est. Priority Date: 10/27/2000
• Status: Expired due to Fees

• Current Assignee: Makex Limited
• Original Assignee: Makex Limited
• Inventors: Bailey, Ralph-Peter Steven
• Primary Examiner(s): Lefkowitz; Sumati
• Assistant Examiner(s): PHAM, TAMMY T
• Application Number:
  US10/432,039
• Publication Number:
  US 20040040805A1
• Time in Patent Office: 2,682 Days
• Field of Search: 345/156, 345/174, 345163- 7, 345/163, 345/164, 345/167, 463 37- 38
• US Class Current: 345/156
• CPC Class Codes: G01B 5/008 using coordinate measuring machines
• CPC Class Codes: G06F 3/016 Input arrangements with force or tactile feedback as computer generated output to the user
• CPC Class Codes: G06F 3/0346 with detection of the device orientation or free movement in a 3D space, e.g. 3D mice, 6-DOF [six degrees of freedom] pointers using gyroscopes, accelerometers or tilt-sensors

Abstract

A haptic input device comprises a hexapod or pentapod parallel linkage mechanism with force feedback effected by proportional control of magneto-restrictive fluid brakes constraining the measurement of the struts of the mechanism, through their base nodes. In the pentapod version of the haptic data input device, a haptic stylus is employed which includes an annular compliant feature that can be squeezed and whose squeeze pressure can be monitored.

Claims

1. A haptic device comprising:

at least five axially moving struts, together forming a parallel link mechanism, each strut having a first end and a second end;

a frame comprising a plurality of brake nodes, each mounted in ball-and-socket manner in the frame, each brake node constraining axial movement of at least one of said struts that passes by sliding movement through the brake node;

a haptic stylus supported by each second end of each said strut;

wherein the struts pass through said brake nodes with sliding axial movement and wherein force feedback is effected by proportional control of brakes in the brake nodes, constraining sliding axial movement of the struts through their corresponding brake nodes, and wherein the haptic stylus moves with at least five degrees of freedom and gives force feedback in three dimensions.

2. A haptic device as claimed in claim 1, where the brakes are effected by causing MR fluid to change its viscosity by adjusting a magnetic field.

3. A haptic device as claimed in claim 2, wherein the MR fluid acts between the rim of a rotary disc and its housing, the disc axle extending out of a fluid filled cavity and retaining a friction wheel that acts capstan-like against the axial motion of a strut.

4. A haptic device as claimed in claim 2, where the MR fluid is in a cavity containing meshing gears and an electromagnet is arranged to create a magnetic field across the gear mesh zone that can be adjusted to adjust the viscosity of the fluid and in turn adjust the resistance to rotation of the gears.

5. A haptic device as claimed in claim 1, comprising a ball end around which two annular sockets attached to struts are clamped by virtue of a partial snap-on ring with opposite inwards faces, the gap between these faces being sufficient to accommodate the two annular socket rings back to back.

6. A haptic device comprising:

at least six axially moving struts, together forming a parallel link mechanism, each strut having a first end and a second end;

a frame comprising three brake nodes, each mounted in ball-and-socket manner in the frame, each brake node constraining axial movement of first respective ends of at least two of said struts that pass by sliding axial movement through each brake node; and

a haptic stylus supported by each second end of each said strut;

wherein each brake node further comprises a pair of hemispherical parts together forming a sphere and wherein each hemisphere supports at least one of the struts and allows the strut to pass through it,

wherein force feedback is effected by proportional control of brakes constraining axial movement of the struts through their respective hemispheres, and

wherein the haptic stylus moves with at least five degrees of freedom and gives force feedback in three dimensions.

7. A haptic device comprising:

at least five axially moving struts, together forming a link mechanism that moves in parallel, each strut having a first end and a second end;

a frame comprising a plurality of brake nodes, each brake node constraining axial movement of at least one of said struts that passes by sliding movement through the brake node;

a haptic stylus supported by each second end of each of said struts; and

wherein the struts pass through said brake nodes with sliding axial movement and wherein force feedback is effected by proportional control of brakes in the brake nodes that constrains axial movement of the struts through their corresponding brake nodes, and wherein the haptic stylus has a position defined in at least 5 axis space and gives force feedback in three dimensions.