Industrial automation has been a pioneering field for robotics. While the food industry is among the most highly automated sectors of manufacturing, unlike other material-handling applications, food handling has been slower to adopt robotic technology. Over the past decade, however, the use of robotic technology has grown in the food sector, typically in picking, packaging, or palletizing operations.
Although the food industry is no longer a greenfield opportunity for robotics, the market is so large that there is still massive untapped potential for robotics applications to improve product quality and yield, and increase the efficiency and flexibility of the food manufacturing production line.
Hygiene and Sanitation
Reasons why the food industry has been slow to adopt robotics vary from application to application, but the overarching technical challenge has been meeting the sterility and food safety requirements. Recently, however, the U.S. Food and Drug Administration (FDA) and equivalent regulatory bodies throughout the world have approved robotic grippers and other specialized technology, opening the food-handling industry to wider adoption of robots.
The line between automation and robotics is a fine one, but in this case it can perhaps best be defined by the use of active manipulation in robotics. However, the alternatives-conveyor belts or gravity-based conveyance, for example-incorporate surfaces that are in contact with food that can be easily sterilized. With robotics technology, such as robotic grippers, more moving parts are in contact with food, and these moving parts can conceal contaminants, and are far more difficult to break down and clean.
Cleaning is a critical requirement for food-handling technology. The FDA has strict regulations that require sanitization, often using caustic chemicals, of any surface that comes into contact with food. An international standard for washdown, IP67, defines the specific sanitary conditions that make equipment handling meat and poultry food-safe. The use of special food-safe lubricants is also required. Robots used in the food industry must meet these requirements, often at a high cost to the companies that develop them.
Although the bar is high, there are tremendous competitive advantages for companies to meet these requirements and offer products for the food industry. Food-handling lines are still heavily staffed by humans who can perform complex manipulation tasks, but the working conditions are harsh-monotonous, dirty, and at times in cold rooms kept only barely above freezing. Turnover among these workers is often high, indicating efficiency and cost advantages for line operators to integrate more automation capabilities.
The Three Ps Lead
Robotics systems in food production are typically used for picking, packaging, or palletizing operations-the “3 Ps.” Initially, high investment costs made food manufacturers reluctant to introduce robots. However, the first generation of systems demonstrated a quick return on investment (ROI), improving throughput rates and cutting costs, as well as allowing food processors to reallocate their line packaging workforce to less monotonous roles.
The most common application for food-handling robots at this time is “primary packaging,” the stage of the line during which food is packed into its wrapper, container, or vacuum-sealed bag. The following step, secondary packaging, is another common application for robots. During secondary packaging, multiple packaged units are packed into cardboard boxes or other storage and shipping containers. These steps are typically less messy than the food processing steps further up the line, and they deal with more regularly shaped objects-an advantage for vision system performance.
Picking, packaging, and palletizing food processing operations have been employed to great success in the food industry. Even so, there is still tremendous room for growth for new types of food packing applications. Currently, robots are primarily working with food products that are grasped without difficulty and easily recognized with vision systems. New classes of robotics systems with the capability to manipulate less rigid objects with greater variability in size, shape, and orientation, will expand adoption of robotics for food production.
It is critical to understand that any manufacturing robot is in fact a complex system comprising end products from multiple vendors. There is the robot-usually an arm, perhaps a multijointed robot arm, or an overhead “picking” arm called a “delta” or “parallel” robot. Separately, there is an end-effector, often customized for a specific application. End-effectors may be differently shaped grippers, suction cups, and other manipulation devices specific to the size, shape, and rigidity of the food products they are handling.
At some point in the line, either co-located with the robot, or more likely further up the line, is a computer vision system that determines the layout and orientation of the food products to be manipulated. As with other steps in the packaging process, a vision system may be required to read bar codes as well.
Safety systems are typically incorporated in the robotic work cells of food-packing applications. Many systems detect if humans or other items come in close approximation to moving parts on the robot and the automated conveyance technology serving it. These safety systems may consist of light curtains, cameras that detect human presence, or even simple physical guards.
The robot and manipulator require special materials to meet food-safety requirements. Stainless steel is a common material, since it can withstand caustic cleaning chemicals. Food-safe lubricants that meet standard National Sanitation Foundation (NSF) H1 regulations must be used within moving parts.
Some manufacturers have addressed the food contact issues by creating specialized “gloves” for the robot, rather than modifying the robot itself to stand up to extreme sanitization processes. These are similar to rubber gloves for humans; they cover all likely contact surfaces and can be removed and disposed of. These coverings even eliminate the need for food-safe lubricants.
The major players among food-handling robots are also leaders in other industrial robotics sectors, such as KUKA Robotics, Motoman Robotics (Yaskawa), Staubli Group, DENSO Robotics, FANUC Robotics America Inc., and ABB. These companies have bundled modified base robotic systems and other technologies to target the food industry.
The manufacturers and their system integrator partners provide the robotic arms used in food-handling lines, and can additionally perform the integration work to install safety systems, vision systems, and other components of the robotic work cell. The opportunities for smaller companies lie primarily in customized parts of the system-such as end-effectors-or in other system support components, like vision systems.
FANUC, Staubli, KUKA, and the others have leveraged their experience with other industrial applications to become de facto choices for food-handling lines. The multijointed robot arms, especially the parallel or delta “picker” robots, are essential for their speed and precision.
The 5-axis FANUC Robotics M-430iA robot was the first robot certified by the U.S. Department of Agriculture (USDA) for meat and poultry processing. The 2008 certification allows the robot to bear the USDA’s AMS Meat and Poultry Accepted Equipment logo, meaning that the M-430iA exceeds NSF/ANSI/3-A 14159-1-2002 specifications.
This announcement was significant, since the meat and poultry work has very stringent hygienic and washdown requirements, exceeding that for other types of food-handling applications.
The certification also signaled that virtually all classes of food production processes are now open to automation. As meat and poultry processing is the poster child for work that is “dirty, dull, and dangerous,” it is ripe for robotic automation and a huge opportunity.
The modifications made to the M-430iA to make it safe for meat and poultry processing are revealing, and representative of what is required in other food-handling robots. The systems are designed to be watertight, streamlined, easy to clean, and impervious to caustic industrial detergents.
The M-430iA, for example, has dual seals to keep out moisture and bacteria, as well as small windows built into the robot body to detect moisture. All hoses, cables, and wires are housed inside the robot’s body, away from food, water, and cleaning fluids. The robot’s housing is pressurized to act as a further sealant.
The M-430iA systems are also designed to limit exposure of foodstuff from the robot itself-the system is lubricated with NSF H1-certified food-grade grease.
Another example of a robotic system optimized for food production automation is ABB’s IRB 360 FlexPicker delta robot. The FlexPicker, which can perform up to 150 pick-and-place cycles a minute, actually meets a cleanroom standard-ISO Class 5. By doing so, the system also meets the requirements for washdown and food safety required for food-handling processes.
Some smaller players have had success with their robotic arm offerings as well, such as Switzerland-based Staubli, a 3,000-person company with customers and offices worldwide. Staubli’s TX series of robotic arms are designed for cleanroom and food-handling environments.
The food-handling industry also makes wide use of computer vision systems. These systems, often installed upstream of a robot arm in order to determine the layout and positions of units to manipulate, face a special challenge in dealing with irregularly shaped food products or overlapping units.
Cognex, for example, provides computer vision systems that can deal with pizzas, beverages, and other food products in quality inspection and packaging applications. The systems include technology to read bar codes and other serialization markers, which has applications in tracking inventory during secondary packaging.
Germany-based Schunk offers a range of components for robot systems, including manipulators and machine visions systems. In particular, it manufactures food-safe manipulators that both grip and stack food products and packages. One Schunk manipulator is large enough to handle an entire butchered pig.
Applied Robotics, a small, privately held company in Glenville, N.Y., received a great deal of press with the 2008 release of its meat gripper end-effector. This gripper, one of the first FDA-approved and the very first USDA-approved end-effector for food handling, can handle fresh or frozen meat, cheese, and other perishable food items, and survive chemical cleaning processes.
Advances in the use of robotics technology to automate food industry processes have been substantial, particularly in the areas of picking, packaging, and palletizing, but many opportunities still exist. As with other forms of industrial automation, the goal is to automate the complete production cycle from raw materials to finished product, beginning with inspection, and on to handling, cutting, processing, and packaging.
There are additional applications upstream in the food processing line, though these tasks require not only greater dexterity compared with 3P applications, but may also at times require more complex autonomy than is currently available. Understanding how to mix pancake batter or pour pancakes onto a line is a much different challenge for a robot system than stacking and packaging the cooked pancakes, for example, and at this time the more complex tasks are better suited to highly customized automated systems than to more generalized robots.
Other processing tasks, such as filling casings for sausages or hot dogs, require significant human intervention for fine-tuned adjustments throughout the process, a capability beyond current robot technology.
Another area that will benefit from robotics, and is therefore a source of opportunity, is quality control. Food products undergo inspection at various points in the processing and packaging line to check shape, weight, size, and other factors. Improved vision systems, hardware integration with digital scales or other measuring tools, and better design and layout of the process line will contribute toward robots’ ability to meet this need.
The fundamental challenge across these new applications is the variability and specificity of food processing lines. As in other industrial applications, nonrobotic automation has had great success due to its ability to be highly customized to a specific product application.
For example, in comparing two hypothetical chocolate bar manufacturing factories, the processing and packing lines would be designed and installed differently depending on parameters such as available human labor, efficiency goals, size and shape of the product, and factory layout.
Robots are typically desirable for manufacturers, since they can be reprogrammed or have end-effectors changed out for new or different food products, whereas installed automation systems may be physically limited in what sort of product they can handle.
However, manufacturers still want the robots to fit into their customization paradigms. Thus, it is important for providers of robotic system components to account for the variability of a processing line, the desire for flexibility and modularity, and the need for customization from customer to customer.
The food-handling space is an especially good opportunity for small and medium businesses. KUKA, FANUC, ABB, and other large companies dominate as providers of robotic arms. However, the endless opportunities for customized end effectors, new vision systems, and other peripherals open the doors to many smaller players. In creating products to work with the well-established industrial robotics companies, developers must address two key issues:
- Regulatory Requirements. Meeting USDA, FDA, and international food safety standards requires a large investment of time and money. For existing companies with non-food-safe offerings they hope to expand, this investment may make sense. Small companies just entering the field may instead find this challenging, particularly without past experience in regulatory compliance. If a company develops a food-specific product, finding other applications for the product will increase production volume and help to amortize the cost of the investment in regulatory compliance. One possible application crossover is pharmaceutical and medical device manufacturing, another tightly regulated industry with many of the same requirements for sterilization. It must also be noted that a regulatory strategy for new products must take into account international business; FDA compliance, for example, does not necessarily mean the FDA-approved product can be sold for the same food-handling applications outside of the United States.
- Speed. In addition to working with standard CAN (controller area network) or EtherCAT (Ethernet for Control Automation Technology) interfaces found in industrial lines, peripheral products such as end-effectors must meet one other major technical requirement: cycle time. Because the robotic arms used in food-handling applications are so fast (such as the FlexPicker at 150 pick cycles per minute), grippers and manipulators must similarly actuate at high speeds, and vision systems must process line information quickly. As an example, an attempt to integrate complex sensing into an end-effector to improve its capabilities could actually introduce latencies that make it prohibitive to integrate into high-speed food-handling lines.
If manufacturers can overcome these obstacles, they are likely to find success in a field poised for rapid growth.
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