3D Modeling in the Design Process of Automated Warehouses

3D Modeling in the Design Process of Automated Warehouses

By Ryan White, Senior Distribution System Planner, O’Neal, Inc.

Article originally appeared in Plant Engineering.

E-commerce changed the way consumers shop…now it's changing the functionality of warehouses and distribution centers.

Supply chains for brick-and-mortar stores were simple in concept, even if they were immense in terms of volume, labor and logistics. Products were distributed in bulk, with cases or containers of goods being picked, packed, shipped and transported. But fulfilling e-commerce orders requires a different methodology. Single items must be picked and packed then shipped in small volumes or as individual pieces...and they are expected to reach consumers' doorsteps in an increasingly shorter timeframe. Companies are also looking to grow in volume and SKUs in order to meet customer expectations. At the same time, labor is becoming more difficult to maintain and hire in order meet these demands. Consequently, distribution and e-commerce warehouses are entering a crossroads where manual warehouses are no longer viable to execute a supply chain strategy. Constructing warehouses that can meet the requirements of e-commerce involves careful planning. It also involves having multiple stakeholders understand and buy into the plan.

3D Planning
Just as manual warehouses are becoming a thing of the past, 2D “CAD design only” drafting in the concept phase of a project is no longer viable. Most automated warehouses utilize their vertical space with many interaction points at different elevations. There's an emphasis on fitting automated technologies into existing brownfield buildings in order to create a better automation business case or Return on Investment (ROI). In most cases, this means technologies use all of the cubic volume to squeeze the most value out of the space. As a result of using the maximum clear ceiling height of a building, systems have multiple levels with different functions or steps in the process at each level. With 2D layouts, the only way to make sense of the material flow is to have a different offset drawing for each level, with connector lines to each transition from level to level. These drawings are difficult to read for customers and engineers alike—the only person that clearly understands the flow in these types of drawings is the solutions engineer who made them!
While 2D drawings still have a place in engineering these complex systems, 3D modeling is now a must for the following reasons:

Helping Stakeholders “Buy-in” to the Concept. Any successful project starts with a plan that everyone understands—from operations to engineering to the owner. Even the simplest of conventional 2D drawings are hard to understand for people who do not use CAD programs every day. 3D modeling allows people with different backgrounds to understand the operation
For example, a client’s engineering team may look at a 3D design for details such as whether an electrical cabinet has a sloped roof, ensuring no dust can collect on top and the cabinet will meet a “clean design” standard. A client’s operation team may look at the same design to check operator workstations where pallets are being unwrapped to ensure there is space for trash bin with a way to empty it. A company’s owner may be looking at the design to make sure the equipment is painted the right color– while this is a simple issue, it is not one that's able to be corrected once the equipment is on site.

A good 3D model will be capable of producing fly-through videos of the facility, so that no area of the concept is overlooked. Lastly, a 3D model with enough detail also gets people excited about the project because it allows them to visualize their operation and helps sell the project to all levels of management.

Collision detection: Automation projects involve multiple firms and disciplines. On a typical unit-load automated storage and retrieval system (AS/RS) project with a building expansion, for example, a project requires the coordination of the building general contractor, the material handling automation vendor, a structural racking vendor, fire protection systems, and more. All of these vendors have their own drawings, requirements and points of interaction with one another. The challenge becomes that all of the engineers and architects on a project must coordinate to ensure their designs do not impact any other engineer’s design. In a 2D only design workflow, mistakes are hard to catch and often result in more engineering hours and lost time in the delivery of a project. A 3D design workflow allows engineering disciplines to catch issues early without lost time – which saves money. Even before engineering starts, a 3D model in the conceptual stage helps ensure the design will work inside a new or existing building.

Risk management: With the demand for new and modern distribution warehouses on the rise, the risk of implementing a project is also increasing. Historically, building a large manual warehouse has been a low risk proposition because in the event of a rapid volume increase or change in business model, an effective response could be implemented by simply hiring more people, adopting a new process or expanding the building. However, when using an automated system, much more planning and resources are needed to ensure its success. Data must be analyzed and interpreted, the operations team must learn to work with automation, and the building utilities (including electrical, compressed air, fire protection systems etc.) must be coordinated and integrated at key points in the system. If an automated system is not well planned at the beginning, redesigning or moving the system is costly and changes take much longer to implement than would be the case in a manual warehouse. Understanding all aspects of a system, before it is purchased or built, is the key to mitigating risk. 3D modeling is one important step to catching mistakes before they are found in the field. Reviewing a 3D model with all key stakeholders provides a chance to review the design and ask questions that engineers have may have overlooked.
In the past, many equipment suppliers and construction firms did not adopt 3D models into their project lifecycle because the models took too long to produce and required high-end computers.

Today, programs like AutoCAD Revit and SketchUp allow for models to be completed quickly while still fitting into a standard workflow—no extra time required. Companies that have expertise in 3D programs can produce models with enough detail and precision to be scale-accurate. SketchUp even allows models to be converted to virtual reality (VR) platforms so that customers can get a first person perspective inside the warehouse.

Success Stories
A 3D model workflow helped catch a costly design mistake early in a project where the automation design had an operator at mezzanine level and a pallet conveyor system on the ground level. After the general arrangement drawing was complete, the architectural team added an egress stair to the 2D drawing to meet a code requirement and to allow operators from the mezzanine to get out of the building quickly in the event of a fire. 2D drawings showed no clash, with a standard-height stair landing expected to clear the conveyor below. However, when the 3D model was created, it revealed that the stair landing would, in fact, interfere if a tall pallet were riding on the conveyor. This mistake would have compromised the effectiveness of the design and limited the height of pallets being stored in the system.

The use of 3D drawings can also identify cost saving opportunities. In a manual distribution facility, there is typically one finished floor elevation for the entire warehouse. Manual material handling equipment such as forklifts and pallet jacks require that a pallet or tote be on the ground level in order to store and access it. Automated storage systems such as a mini-load or a shuttle system, however, are able to store an item on one level and deliver it on another. This allows the automated storage system to have a different finished floor elevation than the rest of the warehouse, with the bottom level of storage being below the finished floor. This can reduce construction costs considerably, since--depending on the topography and elevation of the warehouse site—bringing the entire site to a single grade height can be extremely costly. Site work costs can be accurately estimated when creators of 3D models import site locations from Google Earth, determine a high-level topography and evaluate the amount of site work required to have a single finished floor. In one project, it was determined that having the finished floor of the AS/RS sit lower than the rest of the warehouse would result in a cost savings of $750,000. 

Another example, in which the planning team did not use 3D modeling, involved a warehouse addition that was built to house an automated case picking system. The building addition was approved and engineered before the automation solution was decided upon. It was designed to be the same elevation as the existing building, which meant the site was brought up 10 ft. and the site work for the job was very costly. Later, a case picking shuttle system was awarded. Such systems do not need to be installed at the same finished floor elevation as the rest of the warehouse, since they utilize lifts at the front of the system to get product to each level. In this scenario, if the automated system and the building had been engineered at the same time and planning teams had used 3D modeling, the site could have been left at different elevations – saving the owner hundreds of thousands of dollars, as well as time.

Planning and execution are the two most important aspects of a complicated project. Working with a company that has the experience and capabilities to create 3D models, while also knowing enough about the infrastructure and equipment to integrate all of the pieces of a project, helps mitigate risk and is the start to a successful project delivery.