Image brightness reduction for legged mobile robot

• US 8,406,505 B2
• Filed: 08/25/2008
• Issued: 03/26/2013
• Est. Priority Date: 08/30/2007
• Status: Active Grant

• Current Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Original Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Inventors: Shimada, Takamichi, Yokoyama, Taro
• Primary Examiner(s): ZARKA, DAVID PETER
• Application Number:
  US12/230,130
• Publication Number:
  US 20090060318A1
• Time in Patent Office: 1,674 Days
• Field of Search: 382/153
• US Class Current: 382/153
• CPC Class Codes: B25J 19/023 including video camera means
• CPC Class Codes: B62D 57/032 with alternately or sequentially lifted supporting base and legs; with alternately or sequentially lifted feet or skid B62D57/024 takes precedence

Abstract

In a legged mobile robot having an imaging device (such as CCD camera) for taking an image utilizing incident light from external world in which a human being to be imaged is present, brightness reduction operation is executed to reduce brightness of a high-brightness imaging region produced by high-brightness incident light, when the high-brightness imaging region is present in the image taken by the imaging device. With this, when the imaged high-brightness imaging region is present owing to high-brightness incident light from the sun or the like, the legged mobile robot can reduce the brightness to image a human being or other object with suitable brightness.

Claims

1. A legged mobile robot having a body, arms and legs connected to the body, hands connected to the arms, an imaging device for taking an image utilizing incident light from external world in which a human being to be imaged is present, and a head connected to the body and equipped with the imaging device, the legged mobile robot comprising:

an electronic control unit including a high-brightness imaging region determiner configured to determine whether a high-brightness imaging region is present in the image taken by the imaging device and a brightness reduction operation executer configured to block or avoid high-brightness incident light by driving at least one of the hands, head and legs, thereby executing a brightness reduction operation to reduce brightness of the high-brightness imaging region produced by the high-brightness incident light when the high-brightness imaging region is present in the image,

wherein the electronic control unit further includes an incidence direction determiner that is configured to determine whether a direction of the high-brightness incident light has been identified and an incidence direction determining operation executer that is configured to execute an incidence direction determining operation to determine the direction of the high-brightness incident light when the direction of the high-brightness incident light has not been identified, and

the brightness reduction operation executer drives one of the hands to block the high-brightness incident light and bring the driven hand nearer toward the head until the hand in the image taken by the imaging device becomes larger than the high-brightness imaging region while holding imaging parameters of the human being, thereby reducing the brightness of the high-brightness imaging region when the direction of the high-brightness incident light has been identified, and rotates the head to make the high-brightness incident light fall outside an angle of view and drive the legs to a position where the human being is seen at a center while holding an angle of the rotated head when the direction of the high-brightness incident light is not determined by the incidence direction determining operation executer, thereby reducing the brightness of the high-brightness imaging region.

2. The legged mobile robot according to claim 1,

wherein the brightness reduction operation executer is configured to rotate the head so as to reduce the brightness of the high-brightness imaging region when the direction of the high-brightness incident light has been identified and the driven hand hides the human being.

3. The legged mobile robot according to claim 1,

wherein the brightness reduction operation executer is configured to drive the legs so as to reduce the brightness of the high-brightness imaging region when the direction of the high-brightness incident light is determined by the incidence direction determining operation executer.

4. The legged mobile robot according to claim 3,

wherein the brightness reduction operation executer is configured to drive the legs to make the high-brightness incident light fall outside an angle of view when the direction of the high-brightness incident light is determined, thereby reducing the brightness of the high-brightness imaging region.

5. The legged mobile robot according to claim 1, wherein the incidence direction determining operation executer is configured to determine the direction of the high-brightness incident light by driving at least the hands.

6. The legged mobile robot according to claim 1, wherein the brightness reduction operation executer is configured to rotate the head so as to reduce the brightness of the high-brightness imaging region when a maximum value of the brightness of the high-brightness imaging region exceeds the brightness of the human being.

7. The legged mobile robot according to claim 1, wherein the brightness reduction operation executer is configured to drive the legs so as to reduce the brightness of the high-brightness imaging region when an average value of the brightness of the high-brightness imaging region exceeds the brightness of the human being.

8. The legged mobile robot according to claim 1, wherein the incidence direction determining operation executer is configured to determine the direction of the high-brightness incident light by driving the both hands toward a direction in which the human being is present in the image and driving the head, body and hands leftward and rightward away from the human being until the high-brightness imaging region is eliminated from the image.

9. A method of controlling a legged mobile robot having a body, arms and legs connected to the body, hands connected to the arms, and an imaging device for taking an image utilizing incident light from external world in which a human being to be imaged is present, and a head connected to the body and equipped with the imaging device, the method comprising:

determining whether a high-brightness imaging region is present in the image taken by the imaging device;

driving at least one of the hands, head and legs to block or avoid high-brightness incident light, thereby executing brightness reduction operation to reduce brightness of the high-brightness imaging region produced by the high-brightness incident light, when the high-brightness imaging region is present in the image,

direction determining whether a direction of the high-brightness incident light has been identified; and

executing an incidence direction determining operation to determine the direction of the high-brightness incident light when the direction of the high-brightness incident light has not been identified;

wherein the driving comprises driving one of the hands to block the high-brightness incident light and bringing the driven hand nearer toward the head until the hand in the image taken by the imaging device becomes larger than the high-brightness imaging region while holding imaging parameters of the human being, thereby reducing the brightness of the high-brightness imaging region when the direction of the high-brightness incident light has been identified, and

wherein the driving comprises rotating the head to make the high-brightness incident light fall outside an angle of view and driving the legs to a position where the human being is seen at a center while holding an angle of the rotated head when the direction of the high-brightness incident light is not determined by the incidence direction determining operation, thereby reducing the brightness of the high-brightness imaging region.

10. The method according to claim 9,

wherein the driving comprises rotating the head so as to reduce the brightness of the high-brightness imaging region when a maximum value of the brightness of the high-brightness imaging region exceeds the brightness of the human being.

11. The method according to claim 9, wherein

the driving comprises driving the legs so as to reduce the brightness of the high-brightness imaging region when an average value of the brightness of the high-brightness imaging region exceeds the brightness of the human being.

12. The method according to claim 9, wherein the executing comprises determining the direction of the high-brightness incident light by driving the both hands toward a direction in which the object human being is present in the image and driving the head, body and hands leftward and rightward away from the human being until the high-brightness imaging region is eliminated from the image.

13. The method according to claim 9, wherein

the driving comprises driving the legs to make the high-brightness incident light fall outside an angle of view when the direction of the high-brightness incident light is determined, thereby reducing the brightness of the high-brightness imaging region.