Method and device for evaluating displacement signals

• US 7,912,672 B2
• Filed: 01/19/2006
• Issued: 03/22/2011
• Est. Priority Date: 01/21/2005
• Status: Expired due to Fees

• Current Assignee: Xybermind GmbH
• Original Assignee: Humotion GmbH
• Inventors: Feichtinger, Richard, Löschinger, Jürgen
• Primary Examiner(s): Lau; Tung S
• Application Number:
  US11/795,828
• Publication Number:
  US 20080133171A1
• Time in Patent Office: 1,888 Days
• Field of Search: 702/150
• US Class Current: 702/150
• CPC Class Codes: A63B 2208/14 specially adapted for animals
• CPC Class Codes: A63B 2220/13 Relative positions
• CPC Class Codes: A63B 2220/16 Angular positions
• CPC Class Codes: A63B 2220/40 Acceleration
• CPC Class Codes: A63B 2225/50 Wireless data transmission, e.g. by radio transmitters or telemetry
• CPC Class Codes: A63B 69/0028 for running, jogging or speed-walking movable endless bands A63B22/02
• CPC Class Codes: G01C 21/185 for gravity
• CPC Class Codes: G01C 21/188 for accumulated errors, e.g. by coupling inertial systems with absolute positioning systems
• CPC Class Codes: G01C 22/006 Pedometers

Abstract

A process for evaluating motion signals in three-dimensional space is disclosed. The process includes obtaining a first initial measurement value in a first initial direction which is also a first desired direction; obtaining a second initial measurement value in a second initial direction which is different from the first initial direction; calculating a second desired direction and a second determined value from the first and second initial measurement values, the second desired direction being different from the first and second initial directions; calculating a third desired direction and a third determined value from the first initial measurement value and the second determined value, the third desired direction being different from the first and second desired directions; and converting the first initial measurement value, the second and third determined values into respective first, second and third acceleration values. A device for implementing this process is also disclosed.

Claims

1. A process for evaluating motion signals in three-dimensional space by using at least one acceleration sensor and using a rotational angle sensor or speed sensor, the process comprising the steps of

obtaining a first initial measurement value using the at least one acceleration sensor in a first initial direction in space, the first initial measurement value being a first determined value, the first initial direction being a first direction in space;

obtaining a second initial measurement value in a second initial direction in space using the at least one acceleration sensor, the second initial direction being different from the first initial direction;

calculating, by a processor, a second direction in space and a second determined value from the first initial measurement value and the second initial measurement value, the second direction being different from each of the first initial direction and the second initial direction;

calculating, by the processor, a third direction in space and a third determined value from the first initial measurement value and the second determined value, the third direction being different from each of the first direction and the second desired direction;

converting, by a processor, values measured by the at least one acceleration sensor and a rotational angle sensor or speed sensor into a first acceleration value in the first direction, a second acceleration value in the second direction and a third acceleration value in the third direction;

detecting motion using the at least one acceleration sensor and the rotational angle sensor or the speed sensor to obtain the measurement values; and

processing measurement values of the at least one acceleration sensor so that a resulting calculated signal corresponding to a specific direction is evaluated,

wherein the step of detecting motion comprises determining a beginning time and an ending time from the calculated signal, and evaluating a measurement value of the at least one rotational angle sensor or speed sensor between the beginning time and the ending time.

2. The process of claim 1, wherein the second direction is normal to each of the first initial direction and the second initial direction.

3. The process of claim 1, wherein the specific direction predominately corresponds to a vertical direction.

4. The process of claim 1, wherein the at least one acceleration sensor measures accelerations in three orthogonal directions, the process further comprising the step of processing measurement values of the three orthogonal directions so that a resulting calculated signal corresponding to the specific direction is evaluated.

5. The process of claim 1, wherein the beginning time and the end time are detected using adaptive thresholds.

6. The process of claim 1, wherein a foot strike is measured based on acceleration signals measured during a gait cycle.

7. The process of claim 1, further comprising evaluating measurement values of the rotational angle sensor or speed sensor corresponding to a pronation speed of a foot.

8. The process of claim 1, further comprising evaluating measurement values of the rotational angle sensor or speed sensor corresponding to a rotation of a lower limb of a subject about a longitudinal axis of the lower limb.

9. The process of claim 1, further comprising evaluating, by the processor, a performance of shoes during running based on the step of detecting motion.

10. The process of claim 2, wherein the third direction is normal to each of the first direction and the second direction.

11. The process of claim 9, wherein the process is performed using worn shoes and new shoes and further comprises evaluating, by the processor, a function wear of shoes by comparing measurements obtained for the worn shoes with measurements obtained for the new shoes.

12. The process of claim 9, further comprising normalizing, by the processor, the values of the rotational speed sensor for running speed.

13. The process of claim 9, wherein evaluating a performance of shoes comprises evaluating a performance of shoe inserts.