CONTROL DEVICE FOR LEGGED MOBILE ROBOT

• US 20150073592A1
• Filed: 09/02/2014
• Published: 03/12/2015
• Est. Priority Date: 09/06/2013
• Status: Active Grant

• Current Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Original Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Inventors: KANEKO, Hiroyuki, KUROSU, Chihiro
• Granted Patent: US 9,527,538 B2
• Time in Patent Office: Days
• US Class Current: 700/245
• CPC Class Codes: B62D 57/024 specially adapted for moving on inclined or vertical surfaces endless-track vehicles for ascending or descending stairs B62D55/075; hand-carts with provision for travelling up or down stairs B62B5/02
• 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
• CPC Class Codes: Y10S 901/01 Mobile robot
• CPC Class Codes: Y10S 901/28 Joint
• CPC Class Codes: Y10S 901/29 Wrist

Abstract

A setting unit 33 configured to set a first landing permissible region in order to ground a free leg side foot 16 within an upper tread surface or a lower tread surface of a step existing ahead of a legged mobile robot 1 in a traveling direction, and a setting unit 34 configured to set a second landing permissible region in order to ground the free leg side foot 16 on an edge of the upper tread surface or the lower tread surface are provided to switch landing permissible regions for movement control of the robot 1 according to a step height.

Claims

1. A control device for a legged mobile robot, which causes the legged mobile robot to move on a floor having a step, comprising:

a first landing permissible region setting unit configured to set a first landing permissible region indicating a region of a landing position of a foot of a free leg, which is permitted to ground the foot of the free leg of the legged mobile robot within an upper tread surface or a lower tread surface of the step in a situation where the step exists ahead of the legged mobile robot in a traveling direction;

a second landing permissible region setting unit configured to set a second landing permissible region indicating a region of the landing position of the foot of the free leg of the legged mobile robot, which is permitted to ground the foot of the free leg of the legged mobile robot on an edge of a tread surface in a posture inclined relative to the upper tread surface or the lower tread surface of the step in the situation;

a landing permissible region selecting unit configured to select either one landing permissible region as a landing permissible region for movement control of the legged mobile robot from the first landing permissible region and the second landing permissible region in the situation while switching the selected landing permissible region to the other according to a height of the step; and

a leg motion control unit configured to control motion of each leg of the legged mobile robot in the step based on a constraint condition that the landing position of the foot of the free leg is made present in the landing permissible region selected by the landing permissible region selecting unit.

2. The control device for the legged mobile robot according to claim 1, wherein

when the second landing permissible region is selected by the landing permissible region selecting unit in a situation where the step existing ahead of the legged mobile robot in the traveling direction is an upward step, the leg motion control unit is configured to land the foot of the free leg on the edge of the upper tread surface in a posture inclined relative to the upper tread surface of the step while satisfying the constraint condition, and then, configured to control the motion of each leg in such a manner that, after the foot is rotated in a pitch direction to ground on the upper tread surface, the foot is made to perform a next floor leaving from the upper tread surface.

3. The control device for the legged mobile robot according to claim 1, wherein

when the second landing permissible region is selected by the landing permissible region selecting unit in a situation where the step existing ahead of the legged mobile robot in the traveling direction is a downward step, the leg motion control unit is configured to land the foot of the free leg on the lower tread surface while satisfying the constraint condition, and then, configured to control the motion of each leg in such a manner that, after the foot is rotated in a pitch direction to ground on an edge of the lower tread surface in a posture of the foot being inclined relative to the lower tread surface, the foot is made to perform a next floor leaving from the edge.

4. The control device for the legged mobile robot according to claim 1, further comprising

a third landing permissible region setting unit configured to set a third landing permissible region defined depending on a structure of the legged mobile robot as a region in which the foot of the free leg can be landed without occurrence of interference between the free leg and another leg while limiting the motion of each leg of the legged mobile robot within a range of movement of each leg in the situation,

wherein the leg motion control unit is configured to control the motion of each leg of the legged mobile robot in the step based on a further constraint condition that the landing position of the foot of the free leg is made present in the third landing permissible region.

5. The control device for the legged mobile robot according to claim 4, wherein

the first landing permissible region setting unit is configured to set the first landing permissible region to be dependent on a shape and size of the upper tread surface or the lower tread surface on which the foot of the free leg is to be grounded, and

the second landing permissible region setting unit is configured to set the second landing permissible region to be dependent on a shape and size of an edge of the upper tread surface or the lower tread surface on which the foot of the free leg is to be grounded, and to be able to limit displacement amount of each joint within a predetermined range when the foot is grounded on the edge.