LowCost 3D sensor enables complex robot solution

Robot de-palletizing of pallets with stacked layers of products

It has always been difficult and slow to de-palletize items when they are not accurately stacked, because it was necessary to detect the height and horizontal position of the articles in order for the robot to grip quickly and correctly.

Traditional vision has been expensive and complex. Items must be seen throughout the pallet's stacking height, and the items to be detected often vary in color. It has required complex cameras, lens systems and lights. Even with that, varying heights of each layer cannot be detected.

The type of de-palletizing has therefore often been economically irresponsible.

Ifm has launched a series of 3D sensors based on Time Of Flight detection. This means that they can find positions of objects and give the distance to the object. Thus - 3D data for what is being searched. These sensors have low resolution, but by using them creatively, they can still provide data that makes the solution possible.

Aplica had to de-palletize small plastic cups stacked with pads. The pallets are often not stacked precisely when they arrive at de-palletizing because each layer moves on the pallet. The plastic items vary in color, so even advanced vision would be very difficult to provide the robot with the necessary data. The height of the team is also quite important, because the items cannot tolerate pressing them with the robot tool. Vision will then also not be able to provide the necessary height data.

Ifm's sensor does not have high resolution, so it cannot detect the items. The solution was to let the 3D sensors detect the cardboard's position and height. With the 3D data, the robot can position the tool and go down to the right height and suck on the items with a multi-suction head and grasp the interlayer with grippers. The entire layer is lifted free and the robot moves over and has the layer pad pulled off with suction cups, and the robot moves over and delivers the cups on a lane that then feeds each cup forward.

Many simple robot solutions in Denmark have been solved, therefore Aplica specializes in solving the complex automation solutions.