Spatial motion recognition system and method using a virtual handwriting plane

• US 7,580,572 B2
• Filed: 03/17/2004
• Issued: 08/25/2009
• Est. Priority Date: 03/17/2003
• Status: Expired due to Fees

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Bang, Won-chul, Chang, Wook, Choi, Eun-seok, Kim, Dong-yoon, Kang, Kyoung-ho
• Primary Examiner(s): Kassa; Yosef
• Assistant Examiner(s): Park; Edward
• Application Number:
  US10/801,593
• Publication Number:
  US 20040184640A1
• Time in Patent Office: 1,987 Days
• Field of Search: 382/122, 382/186
• US Class Current: 382/186
• CPC Class Codes: G06V 30/1423 the instrument generating sequences of position coordinates corresponding to handwriting preprocessing or recognising digital ink G06V30/32

Abstract

A spatial motion recognition system capable of recognizing motions in three-dimensional space as handwritings on a two-dimensional plane is provided. The system recognizes motions of a system body occurring in space based on position change information of the system body that is detected in a motion detection unit, displays the recognized motion information on a screen, or transmits to an external device the recognized motion information through a transmission/reception unit or a control signal corresponding to the motion information. A control unit produces a virtual handwriting plane having the shortest distances with respect to respective positions in predetermined time intervals based on three-dimensional track information obtained through tracking, and projects the respective positions in the predetermined time intervals onto the virtual handwriting plane to recover the motions in space.

Claims

1. A spatial motion recognition system, comprising:

a motion detection unit for outputting position changes of a body of the system in space as an electric signal based on three-dimensional motions of the system body;

a control unit for receiving the electric signal outputted from the motion detection unit,

wherein the control unit;

tracks the three-dimensional motions of the system body based on the electric signal outputted from the motion detection unit,

produces a virtual handwriting plane located in three-dimensional space, wherein a location of the virtual handwriting plane is a plane which is most adjacent to a set of respective points which correspond to the tracked three-dimensional motions of the system body in predetermined time intervals, and

projects the respective points corresponding to the tracked three-dimensional motions of the system body in the predetermined time intervals onto the virtual handwriting plane as motion tracks,

carries out a rotation conversion of the motion tracks projected on the virtual handwriting plane into a two-dimensional plane of x and y axes; and

a display unit for displaying the two-dimensional plane outputted by the control unit.

2. The spatial motion recognition system as claimed in claim 1, wherein the control unit calculates the rotation-converted tracks by the following equation:

3. The spatial motion recognition system as claimed in claim 1, wherein the control unit calculates the virtual handwriting plane by performing a linear regression operation.

4. The spatial motion recognition system as claimed in claim 1, wherein the control unit calculates the virtual handwriting plane by performing a least squares regression operation.

5. The spatial motion recognition system as claimed in claim 1, wherein the motion detection unit outputs position changes of the system body in space based on a continuous detection of the position changes of the system body using at least one gyro sensor and at least one acceleration sensor.

6. A spatial motion recognition system, comprising:

a motion detection unit for outputting position changes of a body of the system in space as an electric signal based on three-dimensional motions of the system body; and

a control unit for tracking three-dimensional motions of the system body based on the electric signal outputted from the motion detection unit, producing a virtual handwriting plane having the shortest distances with respect to respective positions in predetermined time intervals based on three-dimensional track information obtained through tracking, and projecting the respective positions in the predetermined time intervals onto the virtual handwriting plane to recover the motions in space,

wherein the control unit calculates the virtual handwriting plane having the shortest distances with respect to positions in the predetermined time intervals, using the following equation;

7. A spatial motion recognition system comprising:

a motion detection unit for outputting position changes of a body of the system in space as an electric signal based on three-dimensional motions of the system body; and

a control unit for tracking three-dimensional motions of the system body based on the electric signal outputted from the motion detection unit, producing a virtual handwriting plane having the shortest distances with respect to respective positions in predetermined time intervals based on three-dimensional track information obtained through tracking, and projecting the respective positions in the predetermined time intervals onto the virtual handwriting plane to recover the motions in space,

wherein the control unit calculates tracks of the positions in the predetermined time intervals that are projected onto the virtual handwriting plane by the following equation;

8. A spatial motion recognition method for a motion recognition system, comprising:

at least one control unit that implements the steps of;

obtaining three-dimensional track information on a system body in space;

producing a virtual handwriting plane virtually in three-dimensional space, wherein a location of the virtual handwriting plane is a plane which is most adjacent to a set of respective points which correspond to the obtained three-dimensional track information of the system body in predetermined time intervals; and

projecting the respective points corresponding to the tracked three-dimensional motions of the system body in the predetermined time intervals onto the virtual handwriting plane as motion tracks;

carrying out a rotation conversion of the motion tracks projected on the virtual handwriting plane into a two-dimensional plane of x and y axes; and

outputting the two-dimensional plane to a display unit for display.

9. The spatial motion recognition method as claimed in claim 8, wherein the rotation-converted tracks are calculated by the following equation:

10. The spatial motion recognition method as claimed in claim 8, wherein the virtual handwriting plane is determined by performing a linear regression operation.

11. The spatial motion recognition method as claimed in claim 8, wherein the control unit calculates the virtual handwriting plane by performing a least squares regression operation.

12. The spatial motion recognition method as claimed in claim 8, wherein the obtaining of the three-dimensional track information on the system body in space is based on a continuous detection of the position changes of the system body using at least one gyro sensor and at least one acceleration sensor.

13. a spatial motion recognition method for a motion recognition system, comprising:

at least one control unit that implements the steps of;

obtaining three-dimensional track information on a system body in space;

producing a virtual handwriting plane having the shortest distances with respect to respective positions in predetermined time intervals based on the obtained three-dimensional track information; and

projecting the positions in the predetermined time intervals onto the virtual handwriting plane and recovering the motions in space,

wherein the virtual handwriting plane is calculated by the following equation;

14. A spatial motion recognition method for a motion recognition system, comprising:

at least one control unit that implements the steps of;

obtaining three-dimensional track information on a system body in space;

producing a virtual handwriting plane having the shortest distances with respect to respective positions n predetermined time intervals based on the obtained three-dimensional track information; and

projecting the positions in the predetermined time intervals onto the virtual handwriting plane and recovering the motions in space

wherein the positions in the predetermined time intervals that are projected onto the virtual handwriting plane are calculated by the following equation;