Benefits of choosing simplified sensing in a manufacturing facility
Discrete sensor technology has come a long way and advanced technology offers many benefits, but there are applications where simpler solutions can provide the same benefits during a project.
- Understand the role discrete sensors play in a manufacturing facility.
- Learn how the technology has evolved and their potential capabilities.
- Determine when the simple solution is sometimes better in an automation project.
Discrete sensor insights
- Camera technologies and other sensing devices have had many advances to help manufacturers do their jobs better.
- Sometimes, depending on the application, manufacturers can get the same or even better results with basic sensor solutions that are cheaper and less prone to problems than an elaborate setup.
The constant need for more data and increased accuracy has pushed sensing technologies to the extreme. Advancements in factory automation have converged innovation with new capabilities. For some applications, this influx of data-gathering devices offers a strong payoff, but for others, it’s fair to wonder if all this technology and information is necessary.
Factory automation in the late 1990s, for example, was a time of technology transitions. Programmable logic controllers (PLCs) had been around for ages but had never been so affordable. Technologies such as time-of-flight laser measurement, industrial cameras and inductive coupling, were new and exciting and becoming more affordable, too.
Controls engineers imagined these advanced technologies and systems as a way of future-proofing all projects. In reality, sometimes they made things more complicated.
For some applications, tried and true (and affordable) sensors could have made the projects more reliable and future-proof from the start.
For example, a project required tracking, counting and ensuring several washing machine cabinet bases were orientated correctly on a conveyor. I wanted to use an industrial camera due to its improving technology. The camera and accessories cost $7,000. After several days and iterations, the camera system worked perfectly. It continued working for about a week before a production worker leaned on a post and knocked the system out of alignment. Realigning the camera system took a whole day.
Tried, true and affordable sensor solutions sometimes win out
Despite its technical advancements and “cool” factor, the camera system wasn’t the best solution for the simple application. The solution that won out involved strategically placing seven basic photo eyes underneath the conveyor to identify what base it was looking at and if certain characteristics were present for quality tracking. The investment was roughly $400, and the sensors were well protected from failure. As an additional benefit, if a sensor failed, rather than calling an engineer in the middle of the night, a maintenance electrician could replace it with a new one.
Another huge benefit of using standard sensors is avoiding buyer’s remorse. Camera technology has its place in more advanced image processing and continues evolving. As cameras add capabilities they also may require proprietary communications or software. It’s easy to swap out basic photoelectric sensors with a PNP or NPN output of almost any brand.
It can be easy to be lured into using more complex technologies, even when simpler options can accomplish the same tasks effectively. Photoelectric sensors have consistently proven reliable for presence detection.
Keep the sensor solution simple
Sometimes it is best to keep the solution simple and clean using the tried-and-true technologies in factory automation. Before starting a project, consider if the task can be completed with a straight-forward, simple solution. Boil down the solution to the lowest common denominator and build up the complexity from there. The project might save money and a few headaches along the way.
Keywords: discrete sensors, factory automation
See additional vision and discrete sensor stories at https://www.controleng.com/mechatronics-motion-control/vision-discrete-sensors/
When has the simple solution paid off for you during a project?