How Embedded Motion Control Has Revolutionized Conveyor Technologies for Material Handling

The concept of using conveyor technology to transport goods from one place to another has been around for centuries. Today, companies can use robotic conveying strategies to maximize productivity and generate the best return on investment.

During Modex 2024 Emmet Stiff, New Business Development Manager – ModSort spoke on the use of conveyor strategies to maximize your productivity and throughput to generate the best return on investment possible.  At this seminar, Emmet discussed the three types of robotic technologies that you'd find in E-commerce, warehouse distribution, intralogistics, or parcel and post centers. He also touched on what conveyor technology has evolved into, which is embedded motion control conveyor technology, and how it can be married to different types of robotic applications that you find in the marketplace today to maximize your throughput.

Robotic Conveyor Systems to Maximize Throughput Transcript

A Brief History of Conveyor Technologies

In 1643 Rene Descartes, the famous French mathematician, came up with the concept of physically describing an object's being in three dimensions, also known as the Cartesian coordinate system. For example, think of a loading ship. An engineer can apply a Cartesian coordinate over it with two axis, x and y. A manual laborer could take a package at x¹, y¹ and convey it up the plank to x², y² and into the hold the cargo ship for venture abroad. Now picture a modern order loading carrier. Of course, the weight and the rate have both gone way up. The material that the system is made of had advanced from wood to alloyed steel. Motors, gearing, belt, and bearings make the system fully automated. But crucially, it is still in one single linear direction at one time. Traditional conveyor networks have always been in one linear direction.

Conveyor OEMs have now discovered how to control packages in two dimensions at the same time. If you pair that with robotic arm technology, what kind of potential could that unlock? We have gone from one linear dimension and now we're into two linear dimensions at the same time with embedded motion control.    

Maximizing Value in Conveyor Applications

In all instances, operators in this space are trying to put as many packages as possible into a vessel or container at one time, because the most expensive kind of air is shipped air. When you're shipping air around the world, not only are you not deriving maximum value, but also generating excess emissions. Operators are trying to maximize density to minimize emissions and increase the profitability of their business.  

Getting as many items into a container as possible means using many different methods, such as a tote, a carton, or polybags – due to both what is the most suitable package for an item and customer demand. In the retail space, they're very focused on the visceral feeling that a customer has when they receive a package through an E-commerce provider. You have to be able to handle a wide range of packages without damage. 

On the other hand, there is a challenge with respect to demographics. With an aging workforce and a high cost of living in certain areas, it's becoming tough to source what once were traditional manual laborers. Advances and requirements from the transportation operators also led to the incorporation of robotics. Robotics is becoming developed enough to successfully replace what is considered “low value” manual labor.

What Are the Main Types of Embedded Motion Control Applications?

There are predominantly three types of robotic applications we’re seeing penetrating into the traditional conveyor network space. We can go back to the Cartesian coordinate system to describe a package or a robot manipulating a package. 

Robotic Arms

First, robotic arms, fixed x-y-z manipulation space. These robotic arms are used for picking and placing, inducting. We see them for container loading or unloading, and they're also used for palletizing and depalletizing. It’s a very popular application space to use robotic arms for palletizing, depalletizing - whether it's flower boxes or cans of Coke.  

Autonomous Storage and Retrieval Systems (AS/RS)

Second, is Autonomous Storage and Retrieval Systems (AS/RSs) which are confined x-y-z, automated vehicles that are like spiders combing a huge structure. They tend to be very large, but they can fit a lot of products within them.  

Autonomous Mobile Robots (AMRs)

And the third type are Autonomous Mobile Robots or AMRs. AMRs guide themselves either by looking at QR codes spaced out on a grid on the floor, or with LiDAR. We're hearing more and more about LiDAR because the autonomous self-driving vehicles that we see on the road rely on LiDAR. It's a radar that detects light. That is a confined x-y moving space, and if they want to go up in the z direction, they typically need to go up a ramp.  So, those are the three types of robotic applications that we're seeing in the sectors of E-commerce, warehouse, distribution, parcel and post, intralogistics. 

The Importance of Object Presentation in Robotic Conveyor Systems

The fundamental thing to do is make sure that when you present an object to a robot, it can clearly see the object. You must ensure the package is cleanly presented to the scanner for induction into the warehouse management system. The warehouse management system needs to scan the barcode to know it is coming into the network. So, human labor needs to orientate the package, get the right depth, make sure it's perfect with good, bright light so it can scan the carton and get it into the system. 

Another key is making sure the product is lit from all sides and the label is clearly defined so it’s not rejected by the system. If you have good object presentation, you're setting the stage to get the highest possible successful pick rate. When you do those two things, you maximize your throughput rate and generate the best return on investment.  

Key Considerations of Automated Material Handling Systems

When we're called upon to supply conveying technology, the first thing we ask is the direction that the package needs to go. In a distribution center, a package must come in, be unloaded, sorted, and go around and find its home, maybe in an AS/RS. Then, the reverse needs to happen. It has to be called upon, sent to the loading dock, palletized, and sent out to the customer. 

Second, what's the environment that we're dealing with? Is it hot or cold? Is it hazardous, nasty, wet, loud? Then you have to pick the type of drive system. Are you going to use motorized drive rollers? Are you going to use an external gear motor? What kind of frame material do you need? Steel? Plastic? It depends on the package type and weight that must be conveyed.  

Then lastly is the conveyance medium for that package to sit on. There are lots of different materials that you can use for your conveyance medium. When you go to an integrator conveyor OEM these are the type of things that we've got to figure out before we can get the right type of technology into your warehouse.  

Why the Right Conveyor Components Are Important

Embedded motion control conveyor technology didn't show up last night, it's been in development for many years.

Conveyor Pusher Arms

As we go around the wheel of embedded motion control conveyor technologies, we start with the classic pusher arm, that delivers a punch. It can be driven with a compressed air pneumatic air system or with an electrical actuator. As the package travels along the conveyor network at a right angle, that pusher arm is going to drive that object off the belt. So, if the system’s designed for a 50-pound object and you put a 10-pound object on there, and that pusher arm hits it, it could knock it way off the side. 

Conveyor Paddle Arms

Then we got the paddle arms, the big sweeping device. The thing to be concerned about with this design is that if it's a heavy box and you've got a big, cantilevered arm, it can generate a lot of torque on that swivel point and that can fatigue after time.  

Pop-Up Belt Diverters

Pop-up belt diverters are electrically driven. Typically, the case rolls on top, the electrical diverter to electricity is fed, the belts pop up, and it diverts the carton off the side. With applications like this, you want to make sure it's a nice, evenly loaded box, because you want each of those belts to get a good grip on the carton.  

Conveyor Swivel Wheels

Now we're going down into the swivel wheel, diverting to different spurs and electrically actuated. The challenge with these is to make sure the package is large enough and has a good enough surface area to get a good grip on all those wheels.  

Activated Roller Belt Technology

Next is activated roller belt technology. This ability to not only transfer packages down the line but divert packages left to right by using compressed air to pop those cylinders up with compressed air to be able to roll left or right. The package is typically driven along one long belt with multiple divert sections, very effective.  

Omni-Directional Roller Ball Technology

The last technology here is the omni-directional roller ball technologies. They are balls embedded into the belt on one-inch pitches. This technology utilizes 24 volts MDR, motorized drive roller ball technology, so it's quiet, energy efficient, and approachable. You can get close to it and work closely with it. It’s necessary for humans to be able to get close to work with these robotic technologies.  

How to Maximize Throughput in Automated Material Handling Applications

Now we can take what we've learned from the history of conveyors, the types of robotic applications that we can encounter, the different types of embedded motion control conveyor technologies, and see how to put these together to maximize throughput. We're going to discuss five real life applications; what the application does, the challenge for this application, and a tip to go along for an operator considering putting that application into their facility. 

Robotic Arm for Pick-and-Place and Induction Applications

The first one is a robotic arm application which is fixed x-y-z for pick-and-place and induction. When packages are cascading down a waterfall and perpendicularly landing on a transfer belt, the robotic arm comes in, observes, segmentizes the packages on the belt, and then decides what to pick.  

The interesting thing about using omni-directional roller ball technology for an induction system is the vision systems can lock sharp definition and pick up the depth of what they're looking at. It features spheres on one-inch pitch, making a nice pattern. When the camera is looking at what's on the belt in front of it, it uses that pattern on the belt to help segmentize the packages. It can make a faster determination of what package is on the belt, what type of package it is, and pick it that much quicker.  

An advantage of using embedded motion control conveyor technology is aligning the package so as they accumulate, they are all in the exact same orientation. When the robotic arm comes along to pick up what it needs to pick up, it’s getting a sure grip. It's getting each package in the right orientation that's aligned to the right sizing of air, so you can quickly palletize a crate. Another interesting thing embedded motion control conveyor technology can do is de-shingle packages. If you have a big clump of polybags all piled on top of one another, you can program a conveyor module to descramble the packages. Eventually it will separate those polybags out into a layout that the robotic arm can quickly segmentize and pick up. 

For those looking to implement a robotic arm into their operations, it's important to provide gapping of the packages once you've picked up an object. As the robotic arm comes and picks one up, you need to ensure that as it drops each package, there is a gap for whatever the downstream application needs to be. Pick-and-place and induction is, aside from depalletizing, the number one application we see for robotics in the conveyor network world.

Container Unloading Applications

The second application is container unloading. The robot steadily picks up packages and then progresses deeper and deeper into the container. It’s trying to get the packages out at a stable, reliable pace. Remember though, that if trucks sit at the dock for a long time, they can get charged a capacity charge - essentially penalty for the truck container sitting there. It's important for the operators to unload that container as quickly as possible.  

Now what happens when you unload that container? One concept is to use embedded motion control conveyor technology to do a pre-sort. You can put some conveyor modules there, along the flex conveyor line, and then do a manual pre-sort.  Doing the pre-sort allows you to get the packages into the AS/RS a little bit quicker. When you're considering bringing in automation technology, be conscious of the floor space that you have available. You also need to understand the SKU count or the number of different types of cartons coming out of the container.  

An interesting thing that some of these automatic container loaders can do is that when the robot picks up the case, it reads the barcode or ISBN number and knows exactly what it is and where it's supposed to go. If it's supposed to go a rack way in the back, in theory, you can set up a completely lights-out, automated system to unload the containers. 

Palletizing and Depalletizing Applications

The next application is a popular one, palletizing and depalletizing. Mixed rainbow pallets are becoming very popular seasonal items. Let's say you're a beer brewer and Christmastime’s coming up and you want to put together a special selection of beers and you want your customer to order 10 of variety A, 10 of variety B, 10 of variety C. That can become a challenge when it comes to palletizing. Using embedded motion control conveyor technology, you can start to split the flow, switch the flow, merge the flow, and change the orientation of the packages as it moves along the conveyor module.  

We've also seen the ability, on a single conveyor network, to set up five spur lines to five different robotic palletizers. So as packages are coming along, you can use the embedded motion control conveyor technology to divert packages to robotic palletizer #1, palletizer #2 and then you're using a single line to feed five different palletizers, rather than having to build five different conveying loops to feed a single palletizer. This is becoming quite advantageous for palletizers, especially when they're trying to palletize difficult products; whether they’re light or top heavy. So going from manual stacking to robotic palletizing utilizing embedded motion control conveyors can significantly advance your throughput.  

Automated Storage and Retrieval Systems (AS/RS) Applications 

The fourth application is the Automated Storage and Retrieval Systems. These were designed around using totes. An AS/RS can be quite large and can be very expensive but can also offer the most storage capability. We've seen Greenfield sites building DCs way out in suburban, exurban land. E-commerce operators are trying to go closer to the urban core and as you go closer into the urban center, you run into the challenge of space constraints. AS/RS manufacturers want to know how to fit more packages into one structure. They can do that through two means; they can get rid of the totes and store the cartons directly or they can use the variable volume storage technology, which is like a smart closet where the shelves condense to fit the carton exactly. Those two factors can really advance your density.  

Why would we incorporate embedded motion control technology? When you're loading a carton into an AS/RS, make sure it's perfectly aligned. If it's skewed, it can be mishandled by the lifts or might not get scanned correctly by the barcode reader, causing it to be rejected and forced out of the AS/RS into recirculation loop. Two things that embedded motion control conveyor technology can do are; make sure that package is perfectly straight heading into the AS/RS and then give the operator an ability to reject packages. 

A tip for people that are looking to add automation with an AS/RS is to understand as the conveyor network is feeding in into the AS/RS, what percentage of cartons are skewed and what your reject rate is. Improving your reject rate will improve your throughput and you must improve that to justify investing in this kind of automation technology.  

Autonomous Mobile Robots (AMR) for Goods-to-Person Applications 

The last application is AMR (autonomous mobile robots), and they are goods-to-person. Goods-to-person is essentially the robot bringing the package to be manipulated to the operator. Traditional AMRs have been guided by the QR codes on the floor. They'll move from one QR code to the next and the network controller will tell them which direction to go. We talked about LiDAR coming in, so it can avoid obstacles that present themselves in the way. AMRs act like little conveyor sections unto themselves. It can look rather chaotic when you see AMRs operating, but it's a very precisely controlled ballet. Every AMR is controlled by the network controller. 

In the past, an AMR had a conveyor module on it that could only convey in one linear direction. As the AMR would come in and receive the package, it would back up and make multiple turns to go where it needed to be. If you start to incorporate embedded motion control conveyor technology, the package can discharge off the back, left, or right. Eliminating the turns made by the robot improves the speed and increases the throughput to maximize the efficiency of your network.  

If you're thinking of incorporating AMRs with conveyor technology, you have to be cognizant of the transfer medium. When transferring from the module onto whatever the receptacle is, make sure to use a conveying medium that has a small radius nose bar, so you can get that tight transfer, because you don’t want to have it get hung up in the middle. This ensures a smooth transition from one side to the other. 

Concluding Thoughts: Generating ROI with Embedded Motion Control

The final recommendation, if you're considering implementing a robotic application embedded motion control application, is to remember what you're trying to do is automate a manual process. You need to understand that manual process and be clear what its steps are. You must be very cognizant on how you measure that manual process's success, with your KPIs in place. Only then can you try to incorporate an autonomous solution or an automated solution. You have to compare Phase A to Phase B. You must ensure that you've improved by incorporating autonomous, automated equipment that is generating ROI. You wouldn’t want to spend a lot of money on automation solutions for it to not improve the process at the end of the day.