The 3D FruitSorter consists of a 3D laser camera that classifies a filled punnet with strawberries based on the measured diameter. The 3D visualization technique is able to create a high-quality image that is easy to process with the vision tools, from which a sorting can be realized according to the sorting classes:
Large 2A: strawberry diameter > 35mm
Large A: strawberry diameter between 31-35mm
Small: strawberry diameter smaller than 31mm
The Vision unit performs the diameter measurement on strawberries located at the top of the punnet. Several combinations of vision algorithms are used for this. The result of the classification is communicated via a Profinet connection to the parent control so that the end result can be registered in an SQL database.
The 3D displacement sensor combines GigE Vision and laser strip lighting to generate information about three-dimensional objects that cannot be easily generated by cameras that acquire two-dimensional images. Each sensor projects a triangular laser plane onto an object as it comes into view. In this way, a matrix of height measurements is built up with which the software is able to create a 2D and 3D image. The height measurement enables the system to distinguish strawberries/fruits from each other, which is not possible with 2D cameras due to too little color contrast.