AUTOMATED SYSTEM FOR WORKSPACE, RANGE OF MOTION AND FUNCTIONAL ANALYSIS

• US 20130324857A1
• Filed: 03/15/2013
• Published: 12/05/2013
• Est. Priority Date: 05/31/2012
• Status: Abandoned Application

• Current Assignee: Regents of the University of California (University of California)
• Original Assignee: Regents of the University of California (University of California)
• Inventors: Kurillo, Gregorij, Han, Jay, Abresch, Richard, Yan, Posu, Bajcsy, Ruzena
• Application Number:
  US13/831,608
• Publication Number:
  US 20130324857A1
• Time in Patent Office: Days
• US Class Current: 600/476
• CPC Class Codes: A61B 2505/09 Rehabilitation or training
• CPC Class Codes: A61B 5/0013 Medical image data A61B1/00011, A61B6/56, A61B8/56 take precedence
• CPC Class Codes: A61B 5/1127 using markers
• CPC Class Codes: A61B 5/7465 Arrangements for interactive communication between patient and care services, e.g. by using a telephone network telemetry of measured physiological signal A61B5/0002
• CPC Class Codes: G16H 80/00 ICT specially adapted for facilitating communication between medical practitioners or patients, e.g. for collaborative diagnosis, therapy or health monitoring

Abstract

A portable and automated system and method for measuring physical function utilizing a contactless and vision-based sensor system for acquiring human movements and methods for the analysis of reachable or functional workspace and range of motion that can be used in tele-medicine applications, such as remote functional assessment and diagnosis. An interactive, shared virtual 3D environment is provided where the patient can follow the movement directions provided by a remote physician while body kinematics are extracted from depth sensing cameras and wireless sensors.

Claims

1. A system for measuring joint angles, range of motion, reachable space, and other motion characteristics of a person, the system comprising:

(a) a plurality of markers for attachment to anatomical landmarks on a person;

(b) a camera for capturing three-dimensional position of the markers;

(c) a computer configured for acquiring images from the camera; and

(d) programming executable on the computer configured for marker detection, marker tracking, 3D triangulation and workspace analysis.

2. The system of claim 1, wherein marker detection is performed by thresholding of a background-subtracted image while searching for a circular-shaped marker within a specific radius range.

3. The system of claim 2, wherein said programming is further configured for classifying the markers based on size, location and color.

4. The system of claim 3, wherein said programming is further configured for tracing the markers over time.

5. The system of claim 4, wherein said programming is further configured for:

for each tracker, determining the corresponding marker from a combination of Euclidian distance and color similarity; and

for all candidates, determining probabilities selecting the marker with the highest probability as the next tracker position.

6. The system of claim 5, wherein said programming is further configured for deterring 3D position from tracker location detected independently in left and right images of the stereo camera.

7. The system of claim 1, wherein said programming is further configured for analyzing a workspace envelope.

8. The system of claim 7, wherein said programming is further configured for transforming tracked 3D hand trajectory into a body-centric coordinate system.

9. The system of claim 8, wherein said programming is further configured for using a body-centric coordinate system to describe the outer envelope of the reached volume.

10. The system of claim 9, wherein said programming is further configured for meshing data to obtain a convex hull.

11. The system of claim 10, wherein said programming is further configured for splitting the mesh data into four quadrants with respect to standardized human body planes.

12. The system of claim 11, wherein the sagittal plane defines the left and right side of the workspace and the horizontal plane defines the top and bottom part of the workspace.

13. The system of claim 12, wherein said programming is further configured for analyzing each quadrant using alpha-shapes and calculating corresponding volume.

14. The system of claim 1, further comprising a remote therapist module configured for communicating with said computer, the therapist module comprising:

(a) a therapist computer with a display;

(b) at least one camera operably coupled to the computer; and

(c) programming executable on the therapist computer configured for communicating with a patient computer, workspace analysis and image rendering.

15. The system of claim 14, further comprising a remote network server module configured for communicating with said computer and the therapist module, the remote network server module comprising:

(a) a computer; and

(b) programming executable on the therapist computer configured for communicating with a patient computer and a therapist computer and data storage.

16. A method for measuring joint angles, range of motion, reachable space, and other motion characteristics of a person, comprising:

acquiring body part motion kinematics in three dimensions from a camera;

measuring bodypart motion trajectories; and

calculating reachable workspace envelope.

17. A method as recited in claim 16, further comprising measuring discrete path lengths of body part movements.

18. A method for measuring joint angles, range of motion, reachable space, and other motion characteristics of a person, comprising:

(a) defining a movement protocol for a body part;

(b) capturing body part trajectories of a subject during performance of the movement protocol for the body part;

(c) fitting trajectories to a workspace template;

(d) transforming fitted trajectories to parameterized coordinates;

(e) determining boundaries from coordinates; and

(f) formulating reachable workspace envelope.

19. A method as recited in claim 18, further comprising segmenting the workspace template into segments.

20. A method as recited in claim 18, further comprising:

calculating reachable workspace surface area; and

calculating reachable workspace volume.