Plug and Play Robotics In Stock and Ready to Ship Now

Everybody know what a robot is but ask 3 different people and you’ll get 4 different definitions. Wikipedia defines a robot as

A machine—especially one programmable by a computer—capable of carrying out a complex series of actions automatically.

Robots are used in packaging for a variety of applications including palletizing, case packing, filling, line loading, labeling, sorting and stacking and more.

Some of the key parameters to be considered when selecting a robot for any operation:

Floor space – Most robots must be enclosed in a cage or protective guarding large enough to assure that it cannot ever reach outside the safety perimeter. Even if the robot’s normal range of motion is limited, the cage still needs to contain the maximum possible. NOTE: This does not normally apply to collaborative robots.

Speed – Robot speed is typically measured in inches per second. Generally, the heavier the load, the slower the robot will move.

Load capacity – The normal and maximum possible weight that the robot must handle must be considered.

Degrees of freedom required – Degrees of freedom is the number of directions that a robot can move at one time. Six degrees of freedom are required to reach any position in a volume from any angle. The human arm has 6 degrees of freedom. It is usually a function of the number of articulations in a robotic arm.

Five types of robots in common use in packaging:

Articulated arm – Articulated arm robots come in all sizes for lifting ounces to hundreds of pounds. They can have six or more degrees of freedom and are useful for performing complex tasks that may vary significantly from day to day.

SCARA (Selective Compliance Assembly Robot Arm) – SCARA robots typically have 3 degrees of freedom X-Y-Z. They can operate at high speeds on repetitive tasks such as placing candies into thermoforms.

Delta – Delta robots are usually vertical as shown. They have 3 degrees of freedom, X-Y-Z but can have additional degrees of freedom such as rotation added at the end of the arm. They are capable of operating at very high speeds. Picking cookies off of a belt and placing them on a flow wrapper infeed at 150ppm + is child’s play for a delta.

Gantry – Gantry robots, also called Cartesian robots, consist of 2 rails supporting a third rail. The 3rd rail runs on the X axis across the 2 support rails. A head mounted on the 3rd rail runs in the Y axis. The head is mounted to the Y rail with a mechanism that allows it to move up and down in the Z axis. A “wrist” mounted at the bottom of the Z arm can provide additional degrees of freedom.

Collaborative – Collaborative robots are robots designed to operate without the safety guarding normally required by other robots. SAFETY NOTE: This is application dependent and safety guarding may sometimes be required.

Robots are just another machine that is available to automate industrial and other processes. Their biggest advantages are their versatility and standardization. Robots are mass produced in large numbers which means that their cost is low compared to purpose built machines performing similar functions.

Case packing, placing a carton, bag, bottle or other package in a corrugated case, is a natural for robots. SCARA and delta style robots may be used in some applications but 6-Axis or articulated arm robots are more common. Their low cost, reach, freedom of movement, and size makes them a natural.   

A common configuration for the robotic case packer uses 2 conveyors. Cases are erected, either by hand or machine, and conveyed to a staging station near the robot. Meanwhile, the product is staged in a nearby station. The closer together all 3, robot and 2 staging stations, can be, the shorter will be the robot travel. Shorter travel means faster cycle time, less wear and tear on the robot and smaller overall footprint.  

Where possible, product should be staged in its final packing format. If bottles are to be packed in a 4X3 pattern, the conveyor can be divided into 3 lanes before the staging station. A backpressure relief mechanism isolates the 4 bottles at the end of each lane. The robot, with an appropriate gripper, picks up 12 bottles at a time and places them in the case. The case is released to the case closer/sealer. 

Additional speed can be achieved in some applications by using a larger robot to pick 24 bottles at once. An articulated gripper spaces them so they can be placed in 2 cases simultaneously. 

It is possible to pick 4 bottles at a time from a single lane but this will require 3 cycles of the robot and each placing position will be slightly different.  

An advantage of the 6-Axis robot is that one robot may be able to pack for 2 separate lines. The case and bottle staging area of each line remain the same with the robot in the center. As the robot is loading one case, the case and product for the other line is staging.  

Some lines may be too fast for 6-Axis robots. Delta and SCARA robots can run much faster and may be a solution in these applications. A drawback may be their limited reach compared to a 6-Axis robot.  

Robotic Palletizers

Palletizing, placing cases, pails or bags onto shipping pallets is a prime candidate for automation. It’s a simple task that anyone with a strong back can perform. The problem is that people with strong backs, willing to do that kind of work, are somewhat difficult to find and keep. It also puts a lot of wear and tear on those strong backs which can result in excess worker’s compensation claims.

Traditional palletizers, such as this one by Columbia tend to be big, bulky and complex, requiring lots of maintenance. They tend to be purpose built and may require modification to handle a different type of product.

Multi-axis robots, such as this Fanuc robot from Frain, are the modern palletizing solution. Robots have so many advantages for palletizing, there is seldom a reason to even think about any alternative. These robots are built by the tens of thousands every year and may be available off the shelf. The only customization needed is programming and the end of arm tooling.

Programming used to be complex but has become simpler every year. It is now within the skillset of the typical maintenance department. Some robots can even be “taught” what to do by an operator manually moving the robot through the task, recording the movement.

End of arm tooling are key to any successful robot. These used to be custom built, could cost as much as the basic robot and took time to deliver. Now many standard designs covering most applications are available off the shelf from a number of suppliers. Typical palletizing applications use suction cups for cases, forks for bags or mechanical grippers for heavy or odd shaped products. Some applications have multiple effectors so that a fork can be used to handle bags. Then, after placing a layer, the robot picks and places a slip-sheet using suction cups before using the forks again to place the next layer of bags

In some instances, a single robot may be mounted between 2 packaging lines alternately palletizing 2 different products onto their pallets.

Collaborative robots may be able to eliminate the need to guarding. This opens the possibility of portable palletizers. These are mounted on either a wheeled or forkable base for easy movement to wherever they are needed.

Best of all, if the robot palletizer becomes surplus, it can readily be reconfigured to a thousand and one other, non-palletizing, tasks.

It seems like I can’t turn around these days without seeing another article about robots. Especially about how robots will be taking over all jobs in a few years. But it also seems like robots and automation are getting confused in the public eye. There’s a lot more to automation than robots.

At Frain we know robots. We work with them every day. With more than 8,000 automated machines in stock, we also know about automation.

Robots are great for a lot of things. They are particularly useful when flexibility is required. Since they are standardized, they can be built in quantity, making them less and less expensive. There are a lot of packaging applications for robots.

There are also some downsides. Speed is one. Try to find a robot that can cap bottles at 400ppm. Complexity is another. They need programming which is something of a specialized skill. Some companies and some geographic locations do not have access to these skills. A robot intended for general use may never be as good as a machine purpose built for a specific use.

Robots can take up considerable space. The robot itself may be compact and may actually only work in a limited area. Moving cartons from the line to a case, for example. Guarding must be provided for all possible areas where the robot could reach.

Note the amount of unused area relative to the working area in the picture below. A dedicated automatic machine with the same function might occupy 20-30% of that space.

Dedicated automatic machinery my not be as versatile as a robot but it will probably be better at what it does. It will certainly, in many instances, be faster. Lines running 1200 bottles a minute are no problem for standard fillers, cappers, labelers etc but no robot could ever keep up.

I’ve been hearing how automation was going to take all jobs since I was a kid. I’ve been hearing how robots were going to take all jobs since the 70’s. What we are hearing today is nothing new and nothing bad.

Automation, whether by purpose designed machines or flexible robots means more efficiency and that’s good for everyone.