Packaging operations leaders face unrelenting pressure for cost savings, increased labor productivity, higher quality, and more. They rightfully turn to automation to drive those improvement efforts. Then there is a fork in the road. Should they consider hard automation systems that can drive the throughput and cost performance required, or robotic cells?
Both types of systems have a place in any modern CPG packaging line. Getting it right in terms of making the investment decision best aligned with your production goals is key. When making this decision, there are five questions you can ask to guide your thought process.
1. What problem are you trying to solve related to degrees of freedom? Most industrial robotic systems have six axes or more to adapt to multiple operations, and mimic the flexibility of a human operator. The caution is to carefully evaluate the operation work center being automated to make sure that this many degrees of freedom are required. If only two degrees of freedom are required, and you have invested in a system that has six or more, you are paying a significant up-front investment and increased operating costs for capabilities the operation does not need. This goes against the fundamental Lean principle of reducing waste, including wasted motion and costs.
An example: A co-packer is currently buying empty cans for their packaging line. The containers are received on pallets and two operators unload those empty containers on a conveyor to move to a filling operation. The co-packer could buy a six axes robot to replace the operators bending down, grabbing a container, lifting the container, and placing it on the conveyor. As they analyze the operation, they realize that this is only a two degree of freedom problem. They can purchase a high speed depalletizing system that simply indexes the pallet up, and sweeps an entire row of containers onto a conveyor. It is more simple, less expensive, more reliable, and easier to maintain.
Matching the equipment to the core of the problem you are solving is key to optimizing your operations.
2. What kind of flexibility does your application require? Robots are inherently flexible. The caution on robotic flexibility is to evaluate what is required in end effectors, and what time and effort is required for program calibration and set up when doing a line changeover. Building a library of end effectors for all the necessary processing steps can increase upfront costs significantly. And while launching a new program can take only seconds, the adjustment of material presentation fixtures, conveyors, and calibrating the set up can take much longer.
Any hard automation system evaluation should include a review of quick change fixtures, jigs, or mechanical or automatic adjustments available. Packing operations require flexibility, and leading hard automation equipment providers have designed and built in quick change capabilities, which rival the change over time of robots between certain container types.
3. What are your space considerations?: When evaluating space requirements, a critical step is identifying the safety zone around the robotic operation. This is typically a zone far beyond the physical structure of the robotic platform. A hard automation system is typically self-contained in the boundaries of the equipment frame.
If you look at an automated depalletizer side by side with a robot, you might think the robot takes up less space, but if you also account for a safety zone boundary around the robot as part of your spatial planning, the footprint consumed by the robot increases dramatically.
While robotic systems can take more of the most valuable space in the plant, floor level, where people, equipment, and material flows, you should also evaluate vertical space constraints. In a typical high ceiling packaging line, vertical space is “free”, and utilizing this space with a vertical automated depalletizer is the right choice. But if ceiling heights are low, a robotic cell working at floor level may be the right decision.
4. Have you evaluated risk for Single Points of Failure? To maximize the ROI on a robotic installation, operations leaders will often have the robot do multiple tasks. This approach can increase productivity – but – can also create significant risks of a single point of failure. When the robot requires maintenance, none of the tasks it was working on can be performed, and safety protocols would drive a complete line-down situation for the duration.
Hard automation typically contains a series of sensors and programmable logic that go in sequence. This can enable a less risky process design via accumulation stages, bypass stages, and equipment access points, such that an equipment failure can be adjusted or repaired while the line remains running.
5. Have you calculated the Total Cost of Ownership and ROI? For key decision makers, using a total cost of ownership analysis can quantify the trade-offs into a clear financial “bottom line.” Which investment will produce both increased throughput (revenue), and decreased costs (all upfront and operating costs). This analysis would include the total costs of fixtures, end effectors, and changeover times for operations that are packaging many different container types.
The total cost of ownership must include machine throughput as well as upfront investment and operating expenses. Automated depalletizers will typically have greater throughput in terms of containers per hour. This can result in a much lower cost per container for an automated depalletizer than a robotic system
The entire total cost of ownership analysis may lead to surprising results when considering if your choice is solving the right problem with the right equipment, and which choice offers the best Return on Investment when considering floorspace, operating costs, maintenance costs, simplicity, and reliability.
Robots and hard automation systems both have a place in modern packaging lines. If the operation requires six degrees of freedom or more (e.g., a programmable welding operation, or a mixed carton palletizing system), the costs, flexibility, and capabilities of a robotic system may be called for. However, when you can solve the automation problem with two or three degrees of freedom with lower total cost of ownership, and a simpler, easier to maintain system, a hard automation system will typically be your best choice.
Take the time to collect the data, evaluate alternatives, and speak with both leading robotic and automation equipment suppliers, and their customers, so you make the right choice – and your automation achieves the positive results your company needs.