Simulation emulation or animation – which is right for you?
21 November 2023
Ganesh Balu explains how different visualisation techniques could transform your next warehouse automation project.
ONE OF the techniques engineers use to validate the design of a complex automated material handling system is to create a working model of the proposed solution to get an idea of how it will perform. The simulation is developed considering the presumptions that have gone into the design, which combine the business rule constraints as well as the equipment and controls specifications.
Before getting into the discussion of a simulation, it is worth discussing other useful models that are also used in the industry and sometimes confused with simulation, namely, "animation" and "emulation." The definitions for each of these are not widely standardised in the industry, so it is always good to check when you are having a conversation with a system integrator to ensure you are on the same page.
Animation for the nation
Animations are typically 3D models of a proposed system created in software that enable zooming, rotation, and often movement of loads, equipment, and operators. They are generally made to create a better understanding of how a system will operate and are extremely useful in presenting to customers who are in a position of approving a project, but not necessarily well-versed in automated material handling from a technical perspective.
Animation ignores most timing and detailed logic. Its purpose is to educate, not validate. However, its importance should not be downplayed. An effective animation is often the only way that key stakeholders can understand how a system will work and what advantages it will bring.
Click here to see an example of an animation: https://bcove.video/49AVkZs
Emulation – a more technical view
Emulation generally means that a virtual 3D model of the system is created wherein even detailed logic is included in the model, including sensor positions, equipment speeds and accelerations, as well as human interfaces, barcode scanners, etc. Higher level software such as warehouse control systems (WCS) may also be included.
Emulations can be very helpful to debug the actual controls of a system before a system is implemented on site. In fact, since this option gives us the ability to create as many loads as needed for any test - and also the ability to look at the entire layout at the same time - this actually means a higher level of controls verification/troubleshooting can be done with emulation than might be accomplished during actual on-site commissioning.
On the other hand, emulations are usually not very adept at looking at system concept design, as the models do not typically contain anything to create controlled variability, take statistics on equipment utilisation, take significant system-level data, etc. These kinds of system concept validation are in the realm of simulation.
Click here to see an example of an emulation: https://bcove.video/3sDsBmg
Generally, the most important purpose of a simulation is to verify that a system concept will meet the required throughput.
A simulation model illustrates the general layout, equipment speeds, operations and controls logic of the proposed system that are all programmed into the model. Typically, key inputs included in the model are the number of buffer positions and appropriate macro controls.
Furthermore, besides just the logic to run the simulation, it is important to program the gathering of statistics about utilisation, numbers of successful transports, and lead times among other points, as these can give significant insight into overall system performance.
Another important factor for simulations is that they include appropriate "randomness" logic/settings that might attenuate events/flows in the same way that they might fluctuate in the real world, even though such a fluctuation might never appear in any data available. The primary function of a simulation is to make sure that a system will be able to meet throughput while following whatever business rules the end-user may have established. That randomness allows engineers to peek into the "what ifs" of day-to-day variations, thus providing quite a solid verification of the concept proposed.
Click here to see a sample simulation: https://bcove.video/3G2QQgQ
Horses for courses? Take your pick.
A system animation gives a very general understanding of how a system will function but does not factor in detailed logic or throughput requirements. Think of it as highlighting how the system will look and a general overview of the flow of goods.
Emulation checks the controls and sensors of the system to ensure that the direction of goods and speed of equipment are all as required.
Finally, simulation looks at throughput and can help identify and eliminate bottlenecks, ensuring that both equipment and operators are being utilised at appropriate levels, which may also include determining the correct number of equipment and identifying the number of operators required, and give hints as to flexibility for future growth. Often, it is discovered that a planned design concept will work, but that tweaks to conveyor buffers, numbers of transport vehicles, and other minor system modifications whether it be in equipment or logic will be necessary, or desirable, for further optimisation.
Whether a simulation is necessary or not depends on the complexity of the system. When in doubt, consult with your system provider for guidance. When it is deemed necessary, a simulation can offer a tremendous peace of mind for all stakeholders.
Ganesh Balu, senior consultant, Daifuku Europe