Gripping system

1. A gripping system for gripping an object using a hand mechanism having at least two finger portions, comprising:

a memory storing a program; and

one or more processors connected to the memory, the one or more processors executing the program to:

determine whether or not a predetermined gripping portion, with which the at least two finger portions of the hand mechanism are brought into contact when the object is to be gripped, is exposed;

specify a contactable portion and an unexposed portion of the object when the predetermined gripping portion is determined to be not exposed, the contactable portion being a portion of the object that is contactable by a first finger portion constituting at least one of the at least two finger portions and the unexposed portion being a portion of the object that is not exposed at a time of the determination and therefore not contactable by either the first finger portion or a second finger portion that differs from the first finger portion;

control the hand mechanism to expose the unexposed portion so that the first finger portion or the second finger portion becomes contactable with the unexposed portion that has been exposed by altering a position or an attitude of the object while causing the first finger portion to contact the contactable portion; and

control the hand mechanism to grip the object in a state where the unexposed portion has been exposed by bringing the first finger portion or the second finger portion into contact with the unexposed portion that has been exposed and bringing a finger portion other than the finger portion contacting the unexposed portion that has been exposed into contact with a predetermined surface of the object other than the unexposed portion that has been exposed.

2. The gripping system according to claim 1 ,

wherein a third finger portion other than the first finger portion or the second finger portion contacting the unexposed portion that has been exposed differs from the first finger portion and the second finger portion, and

wherein the one or more processors execute the program to control the hand mechanism to:

expose the unexposed portion by tilting the object in a predetermined direction so that a bottom surface of the object remains partially in contact with a floor surface while causing the first finger portion to contact the contactable portion; and

grip the object by the unexposed portion that has been exposed and the predetermined surface using the second finger portion and the third finger portion, respectively.

3. The gripping system according to claim 1 ,

wherein the second finger portion is contacting the unexposed portion that has been exposed, and

wherein the one or more processors execute the program to control the hand mechanism to:

expose the unexposed portion which is a predetermined back surface of the object, which is in contact with an other item that differs from the object, by bringing the first finger portion into contact with the contactable portion and, while the first finger portion contacts the contactable portion, shifting the object while pushing the object against the other item; and

grip the object by the predetermined back surface and the unexposed portion that has been exposed using the first finger portion and the second finger portion, respectively.

4. The gripping system according to claim 1 ,

wherein a third finger portion other than the first finger portion or the second finger portion contacting the unexposed portion that has been exposed differs from the first finger portion and the second finger portion, and

wherein the one or more processors execute the program to control the hand mechanism to:

expose the unexposed portion by bringing the first finger portion into contact with the contactable portion and rotating the object in a predetermined rotation direction so that a contact surface by which the object contacts an other item other than the object remains in contact with the other item; and

grip the object by the unexposed portion that has been exposed and the predetermined surface using the second finger portion and the third finger portion, respectively.

5. The gripping system according to claim 4 , wherein

the predetermined rotation direction is a direction for rotating the object in a vertical direction or a direction for rotating the object in a lateral direction.

6. The gripping system according to claim 1 , wherein the one or more processors execute the program to control the hand mechanism to:

when the predetermined gripping portion is determined to be not exposed, move the object toward an other item positioned away from the object by pushing the contactable portion using the first finger portion until the object comes into contact with the other item; and

expose the unexposed portion after the object is brought into contact with the other item by altering the position or the attitude of the object while pushing the object against the other item.

7. The gripping system according to claim 6 , wherein the one or more processors execute the program to control the hand mechanism to alter the position or the attitude of the object while maintaining a state in which the first finger portion contacts the contactable portion.

8. The gripping system according to claim 1 ,

wherein a third finger portion other than the first finger portion or the second finger portion contacting the unexposed portion that has been exposed differs from the first finger portion and the second finger portion, and

wherein the one or more processors execute the program to control the hand mechanism to:

expose the unexposed portion which is a bottom surface of the object, the bottom surface contacting a floor surface, by lifting up a contactable side site of the object while causing the first finger portion to contact the contactable portion; and

grip the object by the bottom surface and the predetermined surface using the second finger portion and the third finger portion, respectively.

9. The gripping system according to claim 1 ,

wherein a third finger portion other than the first finger portion or the second finger portion contacting the unexposed portion that has been exposed differs from the first finger portion and the second finger portion, and

wherein the one or more processors execute the program to control the hand mechanism to:

expose the unexposed portion which is a bottom surface of the object, the bottom surface contacting a floor surface, by lifting up a contactable side site of the object while causing the first finger portion to contact the contactable portion; and

grip the object by the bottom surface and the predetermined surface using the first and second finger portions and the third finger portion, respectively, by bringing the second finger portion into contact with the bottom surface of the object so that the bottom surface of the object is exposed, and in this state, inserting the first finger portion deeper than a position in which the second finger portion contacts the bottom surface of the object.

10. The gripping system according to claim 1 , wherein

wherein a third finger portion and a fourth finger portion other than the first finger portion or the second finger portion contacting the unexposed portion that has been exposed differ from the first finger portion and the second finger portion, and

wherein the one or more processors execute the program to control the hand mechanism to:

expose the unexposed portion which is a bottom surface of the object, the bottom surface contacting a floor surface, by lifting up a contactable side site of the object while causing the first finger portion to contact the contactable portion; and

grip the object by the bottom surface and the predetermined surface using the fourth and second finger portions and the third finger portion, respectively, by bringing the second finger portion into contact with the bottom surface of the object so that the bottom surface of the object is exposed, and in this state, inserting the fourth finger portion deeper than a position in which the second finger portion contacts the bottom surface of the object.

11. The gripping system according to claim 1 ,

wherein the first finger portion is contacting the unexposed portion that has been exposed, and

wherein the one or more processors execute the program to control the hand mechanism to:

expose the unexposed portion which is a contact surface by which the object contacts an item other than the object by shifting the object parallel to a floor surface in a direction for separating the object from the other item contacted by the object while causing the first finger portion to contact the contactable portion, and

grip the object by the unexposed portion that has been exposed and the predetermined surface using the first finger portion and the second finger portion, respectively.