This technology has been employed in a project that concerned the precise
portioning of fish. The aim was to optimise the cutting machine, which
processes the fish filets before the vacuum packing stage, by assisting
in determining the optimal portion cut. This system, concepted and introduced
by our engineers (IBN Ingenierbüro Bernd Beumann GmbH, Mülheim/Ruhr;
www.ibn-gmbh.de), was developed in contract with GEBA Röscherwerke (Bersenbrück, Germany) HS-240.
The system had to meet the specification of being able to process 120 fish fillets per hour. For each salmon filet, the volume and weight needed to be determined so that the cutting machinery could set-up the required angle to cut the fish up into exactly 200g portions for packaging. Before portioning took place, the unprocessed fish fillets were transported along a 200mm-wide conveyer belt where a light source, a structured light laser from Stocker-Yale (Salem, NH,
www.stockeryale.com), was in operation.
Before the data of each filet, i.e. volume and weight, is transferred to the cutting machinery, a further parameter needs to be measured first: the height of the fish on the conveyer belt. For this task, an intelligent camera of the
VCProfessional family from Vision Components GmbH is used. The camera is mounted at a 45o to the conveyer belt in order to measure the path of the laser light at 5mm intervals. After recording this information, the imagery data is interpolated with the other parameters to determine the fishes height. Depending upon what processing step needs doing, a VC4458 unit from the
VCOptimum family of smart cameras may also be employed
At the beginning of each application, the system is calibrated to an object of known height and therefore the recorded height data can be converted in to global coordinates so that the volume of the fish can be determined. Because there is a known relationship between the volume and weight of the fish, the cutting angle of the portioning blade can be finely adjusted so that an exact number of fish slices with optimum weight distribution can be obtained.
The intelligent
VCProfessional Smart Camera was the ideal solution for this application. As the camera is kitted out with a DSP TMS320C64xx from Texas Instruments (TI; Dallas, TX;
www.ti.com), it was possible for us to integrate all image processing routines using the Code Composer on to the camera. When ported, the camera’s digital and serial interfaces allowed us to send commands directly to the SPS unit, which is responsible for controlling the cutting machinery. This meant that the need for a cost-intensive, PC-based solution with additional frame grabber and external camera could be avoided! The control is done solely by the smart camera –this feature is the fact why Vision’s solution has had a substiantial impact on reducing costs.
We now believe that also other manufactures from automated portioning- and packaging systems will be able to profit from this technology in the future, which will lead to optimisations to the production process.
