Automation’s Holy Grail - making sense of all things
06 April 2016
The relentless goal of industrial automation is that machines should not only be able replicate our human capability to make sense of our surroundings, but to go beyond that and achieve processing and communication power.
A key milestone towards that Holy Grail is Industry 4.0; achieving the so-called Industrial Internet of Things, or the Smart Factory, where connectivity and data sharing between machines, not only in a production plant, but across the supply chain, is practically seamless.
There will never be a Smart Factory without smart sensors - it is sensors which are the ‘unsung heroes’; the glue that holds together today’s – and tomorrow’s automated environments.
So, if the Holy Grail of the Smart Factory is to achieve communication between any machines, then the corresponding goal of sensor technology must be to first sense any object, no matter what it is, or what the environmental conditions are. So, how far are we from achieving that goal?
Simply detect any object
The answer is that sensors are already well on the way to detecting and measuring any object, in virtually all industrial automation applications. The accuracy and consistency now achievable with modern sensing means tasks such as picking, placing, labelling and printing can be performed at production speeds, to higher performance levels than ever before, with resultant benefits in low wastage, minimal line downtime and better quality control.
Sensing difficult materials
To begin with, sensor manufacturers like Sick found reliable ways to sense difficult-to-see objects, such as transparent, semi-transparent, uneven and highly reflective objects like glass and plastics in bottling plants, or foil blisters used in pharmaceutical packaging. The new Sick TranspaTect photoelectric sensor, for example, means that reliable and consistent detection of transparent packaging is easy to achieve. By eliminating the need for a reflector and simply referencing the sensor to a convenient machine component surface, alignment problems and false readings are virtually eliminated.
As a different approach, the Sick Glare photoelectric sensor actually uses reflective properties of different materials to reliably detect surface changes and product borders under what could be highly challenging conditions to most conventional sensors.
One sensor for all applications
These are fairly specialist sensing tasks, but could one sensor be developed with the versatility to perform general sensing tasks across the whole range of high-speed industrial production applications? Such an achievement could enable a production engineer to replace most distance and proximity sensors in a production store with a single range of sensors.
Sick believes it has achieved this milestone with the new PowerProx range. This technology has packed the benefits of laser Time-of-Flight (ToF) technology into a compact housing to deliver high-performance distance sensing, proximity and object detection.
Engineers can choose from a range of just four sensors to achieve accurate results over a wide distance range between 10cm and 3.8m without the need for reflectors and receivers.
As a result, even objects being conveyed at high speed, small and flat objects and products with jet-black and shiny finishes, can now be reliably detected over extensive sensing distances and the false readings from spray, dust and reflective lights can be supressed.
The best technology for the task
Laser scanning technology also facilitates using sensing to deliver other measurements, like profile, volume and dimensions, which can be combined to deliver important parameters such as weight, even under such tough industrial conditions like bulk materials handling.
Incorporation of other technologies, including ultrasonics and wave radar, can be used where difficult products must be accurately measured. Sensor development teams work very closely with customers to innovate and adapt to solve real problems.
For example, an application which often defeats sensors is level sensing in low dielectric fluids and foaming liquids, hot or even highly corrosive fluids. Physical factors may also adversely affect conventional level sensing, including challenging tank shapes and materials or locations where tight dimensions limit access by probes and sensors. The Sick LFP fluid probe enables instrument engineers to obtain the accuracy and consistence required, despite the difficulties of specific application conditions.
With an entire range of sensing technology available from capacitive, inductive and photoelectric sensors, to laser ranging, encoding and full 2D and 3D camera imaging and even RFID, a modern sensor manufacturer like Sick is able to match customer needs for technical performance and best application value.
Alongside a comprehensive detection capability, achieving true Industry 4.0 capability means enabling complex data processing within the sensor unit itself, rather than relying on remote processing via the HMI or PLC. This added layer of sophistication comes when IO-Link-based sensor technology is combined with miniature chip processing power built into the sensor.
As a result, a range of advanced functions can be embedded into sensors of all types to provide a powerful new set of tools for the engineer.
Through decentralisation of certain automation functions, smart sensors achieve control and increase the productivity of machines by taking on specific functionality and logical loops that previously needed to be processed higher up in the PLC. Real time events can be locally processed, without waiting for the raw data to be uploaded to the central PLC program, processed and information extracted before action initiation.
With smart sensors on board, automated systems can deliver additional flexibility, reliability and throughput, as well as reduced costs. Advanced functions that have already been developed for smart sensors include a high-speed counter, timer, false tripping suppression, a speed and acceleration monitor and a time-based measurement function to identify products for sortation and picking.
Smart approach to 4.0
The data generated by sensors is the basis for intelligent machine control and automation but, up until very recently, the legacy of a pyramidal configuration for central processing control has slowed progress towards fully integrated factory systems, the dream for Industry 4.0.
Smart sensors are now freeing factory network distributed control systems by removing time-consuming communication bottlenecks between simple sensors and the PLCs. With routine raw data processing tasks performed in real time by smart sensors at machine level around the factory, essential time is saved. The processed data and resulting actions can be made available for recording, safety, traceability and quality control purposes to be overseen at the central system level.
This structured approach to handling data using algorithms and software in the sensors to perform routine tasks at a lower level, and allow central computing to provide factory-wide communication functionality, is more like the way the human brain functions.
Used to its full potential, Industry 4.0 will deliver maximum efficiency while enabling production versatility down to batch sizes of one unit, thus fulfilling the ultimate dream of fully integrated automation.
Contact Details and Archive...