Sheep Auto Bung Cutting System

Summary

Background
MLA works with the red meat industry to  illustrate how current technology can deliver clever solutions to automate manual tasks. An example of this is bung cutting, which is the process of evacuating faecal material from the colon and freeing the bung from its natural attachments.  
In Europe, robotic bung cutting system for pigs has been developed and installed in processing plants.
Research
Inspired by the pig system, MLA, MAR and two sheep processors partnered in an early project (P.PIP.0157) to assess the suitability of the pig de-bunging operator tool manufactured by Freund Germany to be used for sheep processing. Typically, when processing sheep there are two de-bunging related operations which were trialled within this project.
Bung evacuation (pellet removal and or sealing the bung to avoid contamination from faeces present in the colon); andCoring or cutting of the bung.
Unfortunately those trials proved that the evacuation process of the de-bunging tool did not empty the colon to a satisfactory level as it does for pigs.  
The intention of the next set of trials (P.PSH.0443) was to manufacture a bung evacuation tool, connect to the de-bunging tool evacuation system on trial and to evaluate its efficiency for conducting this process.  The results from this trial were inconclusive.
However, following successful offline bung cutting trials it was agreed that to determine whether to proceed with further investment in project P.PSH.0535, Sheep Auto Bung Cutting, online robot trials to ensure any major project risks are alleviated were required.  These trials were carried out under projects P.PSH.0630 and P.PSH.0621.
From the early trials conducted, it was concluded that the bunging operation performed with the Freund Bung Dropper unit did have potential for future manual and/or automated operations in the Australian lamb/sheep industry.
The bung cutter operation worked well and provided excellent freeing capabilities with no pulling required, however the evacuation operation of pellets from the colon was insufficient and did not empty the bung. This would need to be addressed by some suggested future alterations to the equipment but may never be feasible.

The next stage of the development was the integration of the improved bung cutter equipment to a robot as a step to produce a fully automated system.  This was funded under project P.PSH.0535 which attemped to automate this process via integration of the following main elements;Carcass handling & stabilisation (Gambrels & Conveyor Rails)Sensing technologiesMAR developed bung cutting toolRobot manipulatorTool SterilisationCell Safety SystemControl System
Outcomes
 

Through extensive offline and on-line trials project P.PSH.0535 developed a robotic bung cutting tool that, provided it is accurately placed over the bung area, will successfully cut and free the bung.  There are a number of challenges that the system still faces however, including:Sensing required for accurate tool locationInverted bungs caused by the high vacuumCross contamination caused by the stabilisation conveyorQuality of tool sterilisationCycle time concerns with increased carcass rates
While it is felt that these challenges can be overcome there is concern that, with the increased carcass rate proposed at Gundagai Meat Processors (GMP) and the range of carcass sizes and breeds processed at GMP, cut quality and tool cleanliness will be compromised.  While MAR believes that the system could be successful in a plant that runs at a slower carcass rate and processes a more consistent size and breed of carcass, it was felt that the best course of action would be to halt any further work on the system at GMP and place this technology on hold for the moment.