Force reflecting haptic interface

• US 6,853,965 B2
• Filed: 11/16/2001
• Issued: 02/08/2005
• Est. Priority Date: 10/01/1993
• Status: Expired due to Fees

• Current Assignee: Massachusetts Institute of Technology
• Original Assignee: Massachusetts Institute of Technology
• Inventors: Salisbury, J. Kenneth Jr., Massie, Thomas H
• Primary Examiner(s): FREJD, RUSSELL WARREN
• Application Number:
  US10/022,114
• Publication Number:
  US 20030034994A1
• Time in Patent Office: 1,180 Days
• Field of Search: 345/701, 345/161, 345/163, 700/85, 703/6, 703/7, 318/628
• US Class Current: 703/6
• CPC Class Codes: B25J 13/02 Hand grip control means handles or pedals for crane control B66C13/56; for measuring the force applied to control members G01L5/22; hand-held casings for switching devices, e.g. joy-sticks H01H9/0214
• CPC Class Codes: B25J 9/1689 Teleoperation
• CPC Class Codes: G05B 11/01 electric
• CPC Class Codes: G05B 17/02 electric
• CPC Class Codes: G05B 2219/23021 Gesture programming, camera sees hand, displays it on screen, grasp buttons
• CPC Class Codes: G05G 1/52 Controlling members specially adapted for actuation by other parts of the human body than hand or foot
• CPC Class Codes: G05G 2009/04766 providing feel, e.g. indexing means, means to create counterforce
• CPC Class Codes: G05G 9/047 the controlling member being movable by hand about orthogonal axes, e.g. joysticks for switches H01H25/04
• CPC Class Codes: G06F 2203/0331 Finger worn pointing device
• CPC Class Codes: G06F 3/014 Hand-worn input/output arrangements, e.g. data gloves
• CPC Class Codes: G06F 3/016 Input arrangements with force or tactile feedback as computer generated output to the user
• CPC Class Codes: G06F 3/033 Pointing devices displaced or positioned by the user , e.g. mice, trackballs, pens or joysticks; Accessories therefor digitisers characterised by the transducing means G06F3/041
• 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
• CPC Class Codes: G06F 3/0383 Signal control means within the pointing device
• CPC Class Codes: G06G 7/48 Analogue computers for specific processes, systems or devices, e.g. simulators

Abstract

The invention is an apparatus for physically exchanging a force with a user in an environment local to the user. A connection element connects to a user'"'"'s body member and a linkage between the connection element and ground. The linkage includes means for powering at least three independent freedoms of the connection element relative to ground and means for maintaining at least one independent freedom of the connection element relative to ground free of power. Up to three independent freedoms of the connection element may be maintained free of power, and up to five independent freedoms may be powered. Other aspects of the invention include a two actuator counter-balance for controlling a point on a link. The invention also includes apparatus for establishing a virtual, switch, which presents to the user the force and displacement relationship of a spring switch. Another embodiment is a virtual bristled brush, again which presents to the user the force and displacement relationship of such a brush, while also changing the virtual environment to reflect the user'"'"'s changes in location.

Claims

1. An apparatus for generating a signal representative of force, the apparatus comprising:

a receiver for receiving a signal representative of a location of a user reference point relative to a user reference frame;

a geometrical model storing;

a representation of a non-local reference frame;

the user reference frame in relation to the non-local reference frame; and

a conformation of a non-local environment, the conformation comprising a spring-type element relative to the non-local reference frame;

a comparator for comparing the location of the user reference point relative to the non-local environment; and

a force generator for generating a signal representative of a force based on the location of the user reference point relative to the non-local environment and at least one force rule.

2. The apparatus of claim 1, wherein the at least one force rule comprises a spring-force rule which specifies an output force signal in response to a location signal of the user reference point indicative of a deflected conformation of the spring-type element.

3. The apparatus of claim 2, wherein the output force signal is specified by a non-linear function.

4. The apparatus of claim 1, further comprising a non-local environment reaction calculator that makes changes to the representation of the conformation of the non-local environment based on the signal representative of force and the at least one force rule.

5. The apparatus of claim 4, wherein the at least one force rule specifies a change in a representation of the conformation of the non-local environment in response to a location signal of the user reference point indicative of a deflected conformation of the spring-type element.

6. The apparatus of claim 1, wherein the spring-type element is selected from the group consisting of a switch element and a diagonal element.

7. The apparatus of claim 6, wherein the switch element is selected from the group consisting of a virtual push-button and a virtual toggle-type switch.

8. The apparatus of claim 6, wherein the diagonal element is selected from the group consisting of a brush, a sponge, and an eraser.

9. The apparatus of claim 8, further comprising a non-local environment reaction calculator that makes changes to the representation of the conformation of the non-local environment based on the signal representative of force and the at least one force rule, wherein a diagonal element spring-type rule specifies a change in a representation of a cross-sectional area of a selected region of the diagonal element.

10. A method for generating a signal representative of force, the method comprising the steps of:

receiving a signal representative of a location of a user reference point relative to a user reference frame;

storing a representation of;

a non-local reference frame,

the user reference frame in relation to the non-local reference frame; and

a conformation of a non-local environment, the conformation comprising a spring-type element relative to the non-local reference frame;

comparing the location of the user reference point relative to the non-local environment; and

generating a signal representative of a force based on the location of the user reference point relative to the non-local environment and at least one force rule.

11. The method of claim 10 further comprising the step of changing a representation of the conformation of the non-local environment based on the signal representative of force and the at least one force rule.

12. The method of claim 11, further comprising the step of displaying on a visual display the representation of the conformation of the non-local environment as the representation changes over time.

13. A force reflecting haptic interface comprising:

an electro-mechanical device comprising;

a connection element for physically coupling to a user;

an actuator including an encoder; and

a linkage mechanism coupling the connection element to the actuator;

an electrical input/output device; and

a control apparatus for generating an output force signal and an output position signal.

14. The interface of claim 13, wherein the linkage mechanism comprises a series of rotary elements.

15. The interface of claim 13, wherein the linkage mechanism comprises a five-bar linkage.

16. The interface of claim 13, wherein the actuator comprises a rotary actuator.

17. The interface of claim 13, wherein the electro-mechanical device converts an input force signal and an input position signal to a torque value and an angle measurement, respectively.

18. The interface of claim 13, wherein the control apparatus comprises a computer.

19. The interface of claim 13, wherein the control apparatus generates the output force signal based at least in part on an electrical signal that represents an amount of torque the actuator applies in a local environment.