Why wait until you are at your customer’s site, with freshly installed material handling equipment, to test and debug your control system, when you can gain from the experience of hindsight, and test your PLC code, virtually, as you write it, and debug in the comfort of your office?

Controls engineers have one of the most stressful jobs in the world. They are the last step on the critical path of any material handling installation project and are the magicians responsible for turning a complex collection of cables, motors, gears, brakes, rollers, belts, chains, switches, safety equipment, and miscellaneous other hardware, into a fully-functioning, automated system that just works.

Unfortunately, they are also often prevented from starting on schedule because of cumulative problems with design, approvals, ordering, delivery and/or installation earlier in the project. If that isn’t bad enough, they are also the only group that is absolutely not allowed to let their schedule slip, since they would otherwise cause the entire project to be late. Getting a control system operational on time, under the white-hot glare of the customer and various project managers, in an on-site environment, is no mean feat.

The challenge is made all the harder when you consider that, while their bespoke control system code is developed off the critical path back at the office, it traditionally cannot be tested and debugged until the associated hardware has been physically installed on the customer site.

This has a number of drawbacks:

  • Since there is an inevitable time-lag between writing the software and testing it, the controls engineer will need to re-familiarize themselves with their code. In some cases, the commissioning engineer will not have written the control software, and will be required to understand what it does before modifying it.
  • Testing control code on-site often requires jobs to be physically placed at particular locations in order to test that the system responds correctly. Just configuring the system for a test, bearing in mind that other commissioning engineers may be competing for the same resources, can take a long time to accomplish.
  • Testing and debugging code on-site increases site-based costs, such as overtime and expenses.
  • When planning the project initially, the allowance for commissioning the control system tends to be lengthy, increasing the overall project lead time.

We can help.

We create virtual models of the associated material handling system, incorporating all of the physics of the system’s motion, then connect these models to your PLC control system. The virtual models emulate the behavior of the real-life hardware, by responding to control system outputs and generating appropriate control system inputs. We work with your engineers to approve the behavior of the model, ensuring that we create a simulation that accurately captures the behavior of the material handling system to be controlled. Once we have a working simulation, a relatively simple and straightforward process, we hand it over to your engineers so that they can use it to develop, test and debug the control system simultaneously.

We also create test suites for your required test scenarios, automating many elements of control system testing, and preventing bugs from creeping into the control system during development.

The benefits are substantial:

  • Much of the control system testing and debugging can be taken off the project’s critical path, shortening the overall project lead time while also reducing project risk.
  • By removing much of the testing and debugging work from the site operations, we also reduce the commissioning costs by reducing site overtime and expenses. We also allow your best engineers to cover more ground while on site, so that you get the most out of them without the need to hire additional, contract staff.
  • By reducing the time-lag between the development of the code and its testing and debugging, we eliminate the need for the commissioning engineers to familiarize themselves with the entire control system code. Indeed, any issues that survive through to the site commissioning can be reported back to your office to be debugged by your support staff, who then also update the test suites to ensure such bugs do not come back to life.
  • While it is important to perform some site tests, to ensure that the system is wired and configured correctly, many of the tests that require the physical positioning of jobs and equipment can be eliminated. (We recommend that you first validate an emulation against a known working system to ensure that you’re not simply making a leap of faith.)
  • By automating the control system test suite, we reduce the risk that a particular test will be overlooked, providing better guarantees of the quality of the code shipped to site.

We also add metrics and diagnostics to the simulation. Metrics allow the performance of the system to be measured, ensuring that the control system is not introducing delays or bottlenecks into the process, while the diagnostics act as a debugging tool to assist your developers to find and identify the root cause of bugs.

Quite simply, you gain from the experience of hindsight.

If you are scheduled to start development on a new control system, call us now on +1 (313) 451-4001 to arrange a free initial consultation to discuss your requirements and how we can assist you.