Mandayam A Srinivasan

US Patent:

6369834, Apr 9, 2002

Filed:

Jun 2, 1999

Appl. No.:

09/324137

Inventors:

Craig B. Zilles - Middleton WI
Thomas H. Massie - Derry NH
David Lawrence Brock - Natick MA
Mandayam A. Srinivasan - West Newton MA
Hugh B. Morgenbesser - Somerville MA

Assignee:

Massachusetts Institute of Technology - Cambridge, MA

International Classification:

G09G 500

US Classification:

345701, 345702

Abstract:

A method and apparatus for determining forces to be applied to a user through a haptic interface. The method includes the steps of generating a representation of an object in graphic space, sensing the position of the user in real space and calculating a force to be applied to a user in response to the users haptic interface and the users fiducial object. The users fiducial object represents the location in graphic space at which the users haptic interface would be located if the haptic interface could not penetrate the surfaces of virtual objects. In one embodiment, the method calculates a stiffness force to be applied to the user. In other embodiments, the method calculates damping and friction forces to be applied to the user. In one embodiment the step of generating a representation of an object in graphic space includes defining the object as a mesh of planar surfaces and associating surface condition values to each of the nodes defining the planar surfaces. In another embodiment, the step of generating a representation of an object in graphic space includes describing the surface of the object using a coordinate system and associating surface condition values with each set of coordinates of the coordinate system.

US Patent:

6704694, Mar 9, 2004

Filed:

Oct 15, 1999

Appl. No.:

09/418715

Inventors:

Cagatay Basdogan - Pasadena CA
Chih-Hao Ho - Cambridge MA
Mandayam A. Srinivasan - West Newton MA

Assignee:

Massachusetts Institute of Technology - Cambridge MA

International Classification:

G06G 748

US Classification:

703 4, 703 6, 345184

Abstract:

A ray-based interaction system and related techniques are described. The ray-based interaction system and rendering techniques can be used to display haptic interactions between objects having one or more dimensions and a haptic probe modeled as a line segment.

US Patent:

7225404, May 29, 2007

Filed:

Oct 26, 2001

Appl. No.:

10/055565

Inventors:

Craig B. Zilles - Middleton WI, US
Thomas H. Massie - Derry NH, US
David Lawrence Brock - Natick MA, US
Mandayam A. Srinivasan - West Newton MA, US
Hugh B. Morgenbesser - Somerville MA, US

Assignee:

Massachusetts Institute of Technology - Cambridge MA

International Classification:

G06F 3/01
G06F 3/02
G06F 3/03
G06F 3/033
G06F 17/10

US Classification:

715701, 715702, 715757, 715848

Abstract:

A method and apparatus for determining forces to be applied to a user through a haptic interface. The method includes the steps of generating a representation of an object in graphic space, sensing the position of the user in real space and calculating a force to be applied to a user in response to the user's haptic interface and the user's fiducial object. The user's fiducial object represents the location in graphic space at which the user's haptic interface would be located if the haptic interface could not penetrate the surfaces of virtual objects.

US Patent:

7642989, Jan 5, 2010

Filed:

Mar 17, 2006

Appl. No.:

11/378151

Inventors:

Joono Cheong - Pohang, KR
Anuradha M. Annaswamy - West Newton MA, US
Mandayam A. Srinivasan - West Newton MA, US

Assignee:

Massachusetts Institute of Technology - Cambridge MA

International Classification:

G09G 5/00
G05B 13/02

US Classification:

345 21, 345156, 700 45

Abstract:

Systems, methods and computer-executable code stored on computer readable media for synchronizing the evolving state of a dynamic object in a shared virtual environment among a plurality of geographically separated computers connected in a communications network including data communications links introducing time delays in the propagation of data between said computers. The synchronization scheme utilizes an advanced feedback controller to compensate for the state error between sites, comprised of a linear compensator and a Smith predictor based internal model, to determine correct control forces creating a smooth input while maintaining high levels of responsiveness and consistency. A recovery filter for restoring the natural motion of the virtual object distorted by synchronization control is also described.

US Patent:

20070268248, Nov 22, 2007

Filed:

Apr 23, 2007

Appl. No.:

11/739005

Inventors:

Craig Zilles - Middleton WI, US
J. Salisbury - Cambridge MA, US
Thomas Massie - Derry NH, US
David Brock - Natick MA, US
Mandayam Srinivasan - West Newton MA, US
Hugh Morgenbesser - Somerville MA, US

Assignee:

Massachusetts Institute of Technology - Cambridge MA

International Classification:

G09G 5/00

US Classification:

345156000

Abstract:

A method and apparatus for determining forces to be applied to a user through a haptic interface. The method includes the steps of generating a representation of an object in graphic space, sensing the position of the user in real space and calculating a force to be applied to a user in response to the user's haptic interface and the user's fiducial object. The user's fiducial object represents the location in graphic space at which the user's haptic interface would be located if the haptic interface could not penetrate the surfaces of virtual objects. In one embodiment, the method calculates a stiffness force to be applied to the user. In other embodiments, the method calculates damping and friction forces to be applied to the user. In one embodiment the step of generating a representation of an object in graphic space includes defining the object as a mesh of planar surfaces and associating surface condition values to each of the nodes defining the planar surfaces. In another embodiment, the step of generating a representation of an object in graphic space includes describing the surface of the object using a coordinate system and associating surface condition values with each set of coordinates of the coordinate system.

US Patent:

61115770, Aug 29, 2000

Filed:

Apr 4, 1996

Appl. No.:

8/627432

Inventors:

Craig B. Zilles - Middleton WI
J. Kenneth Salisbury - Cambridge MA
Thomas H. Massie - Derry NH
David Lawrence Brock - Natick MA
Mandayam A. Srinivasan - West Newton MA
Hugh B. Morgenbesser - Somerville MA

Assignee:

Massachusetts Institute of Technology - Cambridge MA

International Classification:

G06F 300

US Classification:

345355

Abstract:

A method and apparatus for determining forces to be applied to a user through a haptic interface. The method includes the steps of generating a representation of an object in graphic space, sensing the position of the user in real space and calculating a force to be applied to a user in response to the user's haptic interface and the user's fiducial object. The user's fiducial object represents the location in graphic space at which the user's haptic interface would be located if the haptic interface could not penetrate the surfaces of virtual objects. In one embodiment, the method calculates a stiffness force to be applied to the user. In other embodiments, the method calculates damping and friction forces to be applied to the user. In one embodiment the step of generating a representation of an object in graphic space includes defining the object as a mesh of planar surfaces and associating surface condition values to each of the nodes defining the planar surfaces. In another embodiment, the step of generating a representation of an object in graphic space includes describing the surface of the object using a coordinate system and associating surface condition values with each set of coordinates of the coordinate system.