In a new ‘insights from industry’ Tom Pollard, an RMT Robotics application Engineer for automated warehousing systems talks to Kal Kaur about RMT gantry robot systems.
AZoRobotics - Can you tell me about RMT gantry robot systems and provide a general overview on how these systems work?
Tom - RMT Robotics gantry robots consist of a stationary steel frame, a moving bridge which rolls on the frame and a moving carriage that rolls on the bridge. The gantry mechanism, which is similar to a crane, operates near the ceiling, (above the product to be handled) and reaches down to pick and stack orders. Attached to the gantry robot is a gripper for holding and releasing whatever product we want to handle, from loaded pallets, to layers of product, to small groups or individually selected cases, cartons, bundles, kegs, consumer products, snack food, tires and more. A single robot can cover an area anywhere from 20 to 60 feet wide and 20 to 300 feet long, but has only four motors. Since a single robot can cover large areas and does all its work from overhead, gantry robots are well suited to order picking applications in warehouses where space can be tight and the number and types of products to be selectively picked can be in the hundreds, or even thousands.
RMT has been building these robots for a variety of industries for over 30 years. The robotic gantry is a proven technology that has a significant installed base, is cost efficient, accurate and reliable.
For the warehouse applications, full pallets of product are fed into the system (inventory) and “picked to order” pallets containing exactly what the customer ordered come out in route-stop sequence ready to go directly onto the truck.
AZoRobotics - What design advantages do RMT robotic systems have over competitive products?
Tom - RMT most often competes with a manual handling system, where a worker moves through the warehouse picking products by hand and placing them on a pallet. (When SKU numbers get higher, this process is sometimes replaced by one where the product is picked by hand, placed on a conveyor system which weaves through the warehouse to a central area where the product is palletized or truck loaded by hand.) This process has worked well for decades, but it does have a few shortcomings; it takes up a lot of space, and it gets harder and harder as the number of different products available in the warehouse (SKUs) gets larger, requiring workers to travel farther to pick the same items.
These are the two areas where the robotic solution shines. Since there is no need for walkways and forklift paths through the inventory, the picking system has a smaller footprint than a manual system. With a robotic solution, the cost and space associated with additional SKUs is small, and there is little or no reduction in throughput as SKUs are added.
Another feature that helps with space utilization is RMT’s intelligent replenishment routine. Using a look-ahead window methodology, we only request replenishment product that will be needed within the look-ahead window (typically 30-60 minutes). By only storing what is actually needed for upcoming orders, the amount of inventory in the picking module is dramatically reduced.
AZoRobotics - How has robotic automation technology in the industry evolved to the present day?
Tom - Over the past 10 years RMT has been focusing its gantry efforts on gripper technology that now allows its solutions to stack/move and pick loaded pallets and layers of products with the same gripper/robot. This includes all products typically found in beer distribution, (except kegs) and over 95% of consumer products.
AZoRobotics - How have RMT gantry robotic systems influenced production sequencing capabilities and how do the RMT robotic systems compare to old production sequencing systems with regard to performance?
Tom - Another shortcoming of the manual order fulfillment process, (and of most other automated order fulfillment systems) is that orders are not filled in the sequence in which they are needed for delivery. Workers operate at varying speeds, filling orders of different sizes which require different travel distances. Most automated systems break orders into “waves” to increase their efficiency by only accessing a few SKUs at one time. The sequence in which the orders are filled is changed to suit the order picking process, (often completely filling no orders for long periods, followed by a flood of order completions at virtually the same time). To deal with this issue, most distribution centers allocate areas of the warehouse for “staging” of truck orders prior to loading the truck. Many will also load the trucks a day or two ahead of when they are to be shipped, leaving the loaded trailers in the yard. These processes tie up the inventory, use up valuable space and add labor.
RMT’s gantry solution is unique in that the picking system has access to all products for picking at all times. Orders are filled in any desired sequence. So RMT order fulfillment systems fill orders in a way that makes truck loading, and eventually unloading, as easy as possible. This can include picking the orders to suit the route stop sequence for the truck. Staging areas on the dock are not needed as pallets emerging from the system can go directly onto the truck. Orders can be changed at the last minute with little or no reduction in throughput. Order pallets come out at a consistent high rate. Each truck, each pallet, each order is completed before the next is started. (Typically order picking does not begin until the truck/trailer is parked at the dock. The truck is loaded directly from the automated system and drives directly to the customer). Even the sequence in which products are placed on pallets can be tightly controlled to optimize load stability and product density based on the contents of the order pallet.
AZoRobotics - How does the RMT solution work to provide increased storage capacity and higher throughput with increased SKUs (KZ)?
Tom - Most facilities are tight on space and RMT’s gantry based solutions are designed with space savings in mind:
Inventory is stored compactly - There is no need for forklift aisles/walkways/pick lanes or racking.
The pick system contains only the inventory needed for upcoming orders. Inventory is stored/replenished in even pallet load quantities. Replenishment activities are anticipated and scheduled.
Products can often be stacked higher – Stack height is not limited by a workers reach.
Orders are picked in sequence (RTS) - Staging areas for picked orders may not be needed.
Additional SKUs require little additional space and typically don’t affect throughput.
AZoRobotics - Can you give me a general overview on the impact gantry robotic systems have had on the cost efficiencies among RMT clients and how this has helped meet production demands?
Tom - Most customers base their purchases on a return on investment expectation based on labor savings. What is typically not considered, but represents additional return is:
Traffic associated with picking activities is eliminated.
The fully automated system provides 100% pick accuracy. RMT’s order fulfillment systems also maintain a constant up-to-the-minute inventory of all products within the system. The location and quantity of all products is known at all times.
Reduced product loss
Product is robotically picked and conveyed, not fork trucked, eliminating the damage sometimes caused by forklifts and workers during the picking process.
The removal of the pick lanes means tighter inventory storage and less floor space required to store product. This space can sometimes be used to reduce the amount of off-site storage needed, with the consequent reduction in product damage and costs of trucking.
Just in Time Order Fulfillment
Each truck, each pallet, each order is completed before the next is started. “Last minute” changes can be made with little or no loss of throughput, ensuring the right product goes to the right customer, based on the latest information available.
AZoRobotics - Who are your customers and what is the common target market for RMT robotic technology?
Tom - RMT solutions are ideally suited for companies in competitive markets handling high volumes of labor-intensive products with relatively low margins where the only way to improve profitability is by reducing costs and improving service levels. We have a strong presence in the tire industry worldwide and develop order fulfillment systems predominantly for the snack food, beer, dairy and bakery industries.
AZoRobotics - From your current white paper titled: Above and Beyond: How the High Flying Gantry has Created a Mind Shift in production Sequencing’, Tom Sirianno, Vice President Engineering, T&WA touched on the installation of gantry robots and states that “the biggest challenge was integrating the controls and computer systems to ensure they would work with products from our client, Toyota.” Based on the RMT client profile, how does the integration of controls and computing systems of the gantry robots compare between different manufacturing industries?
Tom - Integration of our systems with the customer’s information systems is a part of virtually every project. The amount of data to be exchanged can be significant. Customer systems can be anything from SAP or Red Prairie to homegrown software packages. Each is different, regardless of the industry.
AZoRobotics - Whilst still on the subject of challenges with the gantry robot system, how have RMT prepared for possible system failures on a manufacturing site? Are there backup systems in place to overcome system faults?
Tom - For multi-gantry solutions, each gantry typically works “standalone” or autonomously, unaware of the presence/absence of other gantries. The RMT WCS distributes tasks to each gantry robot as needed to fulfill the overall need. Each transaction is recorded both in the individual gantry control system and on a central server which carries the WCS. Each is able to back up the other in the event of a failure. If a given robot is unavailable, its tasks may often be reassigned to other gantries in the system. If throughput needs grow in the future, robots can be added to the system, with little or no changes to the existing software.
AZoRobotics - What have been the most rewarding and challenging projects for RMT Robotics and how has this influenced the changes in the design and engineering of RMT robotic systems?
Tom - This is one of the most difficult questions to respond to as every project has had an impact on us one way or another. RMT’s solutions have evolved and will continue to evolve as customers’ material handling needs become more complex. The real game changer for RMT was the successful installation of a high-speed case picking solution developed for a large snack food supplier in the central U.S. The system reflected the 30 years of experience RMT brings to the table in robotic automation solutions and opened the door for further innovation which led to the recent sale of a large-scale robotic case picking solution to one of North America’s largest beer distributors. The system, which has a footprint of less than 40,000 square feet, is designed to pick 300 SKUs at a rate of more than 250,000 cases per day. Every new system we develop is influenced by our past experiences and has contributed to our success in creating long-lasting reliable robotic solutions.
AZoRobotics - What will RMT do to make sure this company is one step ahead of the competition in the current market?
Tom - Staying competitive is the fundamental challenge for any company and keeping a competitive edge was at the forefront of the decision to expand and improve our existing footprint by combining the efforts of RMT Robotics and Cimcorp Oy, who acquired RMT Robotics in July of 2010. Both our companies have over 30 years’ experience in similar industries, paving the way for collaboration between our technical people and allowing them to exchange experiences and designs ideas. The collaboration has also helped us gain insights and knowledge that each of the companies independently would not have gained. Our number one priority is creating and supplying concepts, solutions and products that give our customers the ROI that they require to invest in our technology. We believe that our experience and excitement to drive the technology forward will keep us one step ahead of the competition.