sucker bias principle

Select CenterPrior , try the pose without offset first (the center of the sucker is aligned with the center of the box), try an offset (center misalignment) pose after the path planning fails; CornerPrior is the opposite, and it will try the unbiased pose at last. The relationship between the relative size of the sucker and the box is divided into the following five cases, and there are 1 to 3 types of grasping postures in each case. In different cases, the preferred sequence of attempts for each posture type is as follows.

Attention

CornerPrior is applied to mixed stacking to reduce collision angles, so if the placement after grabbing is not mixed stacking (such as on a conveyor belt), CornerPrior is not required.

Note

In the following illustration, orange is the box, and gray is the sucker.

Scene 1:

1. sucker short side < box short side < sucker long side < box long side

2. sucker short side < sucker long side < box short side < box long side

Actual grasping position:

Scene 2:

sucker short side < box short side < sucker long side < box long side

Actual grasping position:

Method 1:

Method 2:

Method 3:

1. When CenterPrior is selected, the grasping method order is: 1 -> 2 -> 3 (If the ratio of the sucker short side to the box long side is less than 0.25, then: 1-> 2)

2. When CornerPrior is selected, the grasping method order is: 3 -> 2 -> 1 (If the ratio of the sucker short side to the box long side is less than 0.25, then: 2-> 1)

Scene 3:

Box short side < sucker short side < sucker long side < box long side

Method 1:

Method 2:

1. When CenterPrior is selected, the grasping method order is: 1 -> 2

2. When CornerPrior is selected, the grasping method order is: 2 -> 1

Scene 4:

sucker short side < box short side < box long side < sucker long side

Method 1:

Method 2:

1. When CenterPrior is selected, the grasping method order is: 1 -> 2

2. When CornerPrior is selected, the grasping method order is: 2 -> 1

Scene 5:

Box short side < box long side < sucker short side < sucker long side

Method 1:

Method 2:

1. When CenterPrior is selected, the grasping method order is: 1 -> 2

2. When CornerPrior is selected, the grasping method order is: 2 -> 1