Projects 3D Robot Vision For De-palletising

Depalletising heavy products such as large sacks of tea, flour or cement is a challenge for humans because of the dangers involved with heavy lifting. Removing a sack from a towering pallet of sacks is hard physical work.

This is an example of an industrial application that would be solved by robotic lifting. Until recently however, picking a sack from a pallet was a difficult problem to solve because the ideal presentation of sacks is uniform and tidy. The reality though is often very different as product moves during transport and the height, plane and shape of a sack cannot easily be determined using standard 2D vision systems.

The system deals with poorly laid out tea sacks that are threatening to slide off the stack. The Scorpion 3D Stinger camera builds a 3D point cloud that is used to model the top layer of the tea sacks. Using a combination of 2D image data and 3D point cloud data, Scorpion Vision Software works out the height, position and pose of the sack in space.

The robot is confidently supplied with this data and so is able to rotate and adjust the end effector to collect the sack from the stack, no matter how it lies or the angle at which it lies. Should the sack be split, or the angle at which the sack is lying is too extreme, the vision system will stop and await intervention to rectify the problem so the likelihood of split sacks being picked is minimised (and in fact is very unlikely).