Method for making mobile unit accompany objective person

• US 20060064203A1
• Filed: 07/06/2005
• Published: 03/23/2006
• Est. Priority Date: 07/07/2004
• Status: Active Grant

• Current Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Inventors: Okamoto, Tamao, Goto, Takanori
• Granted Patent: US 7,702,420 B2
• Time in Patent Office: Days
• US Class Current: 700/245
• CPC Class Codes: G05D 1/0246 using a video camera in combination with image processing means
• CPC Class Codes: G05D 1/12 Target-seeking control
• CPC Class Codes: G05D 2201/0217 Anthropomorphic or bipedal robot

Abstract

A method for making a mobile unit accompany an objective person moves the mobile unit in correspondence with movement of the objective person and executes control so that the mobile unit moves along the walking direction of the objective person by detecting the foot landing of the objective person, detecting the walking speed and the walking direction of the objective person, and predicting the predictive walking range of the objective person on the basis of the detected information of the walking direction and the foot landing.

Claims

1. A method for making a mobile unit accompany an objective person for moving a mobile unit in correspondence with movement of an objective person, the method comprising:

detecting landing of a foot of the objective person;

detecting a walking direction of the objective person; and

executing control so that the mobile unit moves along the walking direction of the objective person by predicting a predictive walking range of the objective person on a basis of detected information of the landing and the walking direction and detecting that the foot of the objective person lands within the predictive walking range through walking of the objective person.

2. The method for making a mobile unit accompany an objective person as claimed in claim 1, wherein when it is detected that the foot of the objective person lands outside of the predictive walking range, control is executed so that the mobile unit stops moving, and thereafter, the foot landing of the objective person is detected again, the walking direction of the objective person is detected again, and the control is executed through the prediction and the detection of the foot landing within the predictive walking range, so as to make the mobile unit accompany the objective person for moving the mobile unit in correspondence with movement of the objective person.

3. The method for making a mobile unit accompany an objective person as claimed in claim 1, wherein the predictive walking range is a sectorial range directed along the walking direction and having a radius R calculated by a following expression from a footstep of the objective person centered on position coordinates of a landed foot of the objective person;

Footstep×

1.2≦

radius R≦

(footstep+objective person'"'"'s shoes size×

1.2.

4. The method for making a mobile unit accompany an objective person as claimed in claim 1, wherein, when the foot landing is detected, the objective person is discriminated, and position coordinates of both feet of the objective person are detected.

5. The method for making a mobile unit accompany an objective person as claimed in claim 1, wherein, when the foot landing is detected, both feet of the objective person are detected, and position coordinates of both feet of the objective person are detected.

6. The method for making a mobile unit accompany an objective person as claimed in claim 5, wherein, when the position coordinates of both feet are detected, a foot of the objective person located at same position coordinates for a time longer than a prescribed time is determined to be a landed foot, and position coordinates of the landed foot of the objective person are stored.

7. The method for making a mobile unit accompany an objective person as claimed in claim 6, wherein, when the foot of the objective person located at the same position coordinates for a time longer than the prescribed time is determined, the time during which the foot is located at the same position coordinates is set longer than 0.1 seconds.

8. The method for making a mobile unit accompany an objective person as claimed in claim 5, wherein, when the position coordinates of both feet are detected, the position coordinates of the foot of the objective person landed on a ground are detected, and the detected position coordinates of the foot of the objective person are stored.

9. The method for making a mobile unit accompany an objective person as claimed in claim 1, wherein, when the control is executed so that the mobile unit moves along the walking direction of the objective person, a mobile unit movement direction is determined by connecting a midpoint of a line segment that connects both feet of the objective person with a midpoint of a line segment that connects both feet of the objective person at next step from already detected position information of both feet of the objective person, and the mobile unit is moved according to the determined direction.

10. The method for making a mobile unit accompany an objective person as claimed in claim 1, wherein, when the mobile unit is controlled to move, the mobile unit is made to move along the walking direction preceding the objective person.

11. The method for making a mobile unit accompany an objective person as claimed in claim 1, wherein, when the mobile unit is controlled to move, the mobile unit is made to move along the walking direction postceding the objective person.