At this point in 2020, you’d be hard-pressed to attend an industrial automation conference without seeing “simulation” and “virtual commissioning” dotted across technical sessions, keynote speeches, and exhibitor messaging. The increase of this language is for good reason – companies are increasingly turning to simulation-based development techniques to save on the costs of testing against physical prototypes. Machine simulation is now a mainstream technology that can be picked up by even smaller companies looking to ship better products that still fit within tight budgets.
What kind of simulation are we talking here? Your company would likely benefit from a variety of simulation-based technologies on the market. Some technologies help simulate material flow across an entire plant, while other simulation tools help you study individual part deformation.
Here, I’ll focus on machine-level simulation, which is concerned with the dynamics of a single machine in operation. By simulating the performance of an entire machine – electric motors, hydraulics, multibody motion, and more – engineers can hone in on performance requirements, adjust design parameters, and spot issues otherwise missed.
1. Take the Guesswork out of Component Sizing
Every company has their own collection of
techniques when it comes to component sizing for new machines. These might
include some specialized software tools, but often they’re a mixture of
steady-state calculations done by spreadsheet, intuition by the engineer’s past
experience, and a healthy safety factor to account for any variability.
With machine-level simulation tools, you’ll have access to forces, torques, electrical requirements, and key variables you need to consider when sizing components. These simulation results are dynamic, meaning you won’t miss any transient loading behavior, no matter how short-lived. You can use the results to drastically reduce the margins you might be imposing on certain component sizing techniques. For a large production run of a machine, the unnecessary costs of oversized motors can add up quickly.
2. Get Higher Performance without Upgrading Parts
The same simulation results that helped you with component sizing can also shine a new light on tweaking machine performance. Machine-level simulation tools can perform simulations fast enough that optimization tasks can be handled in minutes.
Let’s say you want to see how fast a new
machine can run, given a certain set of motors and other components. In the
simulation tool, you’d be able to fix the parameters that you do know of your
design, and proceed to run an optimization to see how other parameters, such as
cycle time, can be optimized. The results would show you the physical
limitations of a given machine, which might show you that it could be run 15%
faster without any negative impact on the other parts.
Faced with the choice of upgrading a particular motor for a new machine? With simulation results, you might see that only a small spike in forces would require the larger motor. Instead, you could slow down the machine for a fraction of its duty cycle, and speed it up for the remaining sections where the forces are easier to provide. The resulting outcome is the same, but now without the added cost on your BOM.
3. Get Your Products Out the Door Faster
Many internal slowdowns have to do with coordination. New designs need review meetings, collaboration with other teams, and physical prototypes add yet another cycle that can somehow stretch weeks into months. To help cut out some of these slowdowns, simulation tools can give you quick answers to the “what if” questions that might come up during the design process, and eliminate issues before you arrive at your first prototype.
For example, imagine a typical design review meeting, where the choice is made to modify a design parameter. Instead of leaving the meeting room, and returning with an impact analysis a week later, you could come to that meeting armed with a simulation tool. You’d modify, for example, the target load, and re-run the simulation in seconds. As a result, you’d be able to discuss the impact, with no need to wait days to bring this information to the table.
4. Ship a Machine with Fewer On-Site Issues
The reality of high-performance machine design is that, no matter how carefully engineers proceed with development, some level of on-site issues can arise after a machine is shipped. The reasons for these are myriad, and it’s no surprise that some issues slip through the cracks. Developing a modern automation tool is a complicated web of design experts, and cross-communication is difficult.
Using a simulation tool can help reduce these issues. Depending on the detail you invest into a simulation model, a simulation tool never makes a human error, or forgets to double-check a decimal place. For this reason, they’re great at spotting certain design issues that you might overlook, especially when these issues arise due to the integration of different domains of engineering. Even if you’ve got most design issues sorted, simulations can help you test for weak points, by varying frictions, loads, and other parameters. Robustness testing with machine-level simulations is another layer of security that you’ll have for both yourself, and your customer, when shipping a new machine.
5. Quickly Debug and Improve your Controller Code
One of the most variable design phases in
industrial automation is bringing the physical machine together with PLC, and
testing the controller code that governs the machine’s behavior. Ranging from
weeks to months, machine commissioning can involve multiple cycles, and can
require both controller code revisions and machine redesigns.
Common automation software platforms can now integrate with machine simulations and offer a virtual test bed for controller design. By importing the model into automation software, a control engineer can test code in real time against the virtual machine. Some of these automation platforms now give engineers the ability to view their machine simulation in a 3D visualization tool. Here, they can quickly see if their proposed control code has the intended effect on the machine.
Testing control code against a simulation machine won’t solve all of your commissioning issues, but you’ll likely catch a significant amount of the issues you’d otherwise encounter in the longer, more expensive phase of traditional commissioning. For any company, even a modest reduction in commissioning timelines will pose a meaningful reduction in costs, and give your customers a greater confidence in your ability to ship machines, on time and on budget.