SICK insight: Why is the time now ripe for a new technological trend that is supposed to set new standards?

Wilhelm Schürmann: The time is always ripe for new ideas – and the search for new standards has always been our motor for innovations. In the 80s, with the development of the first SICK ASICs (application-specific integrated circuits) in photoelectric switches, SICK laid the foundation for continued success and market leadership in worldwide competition. The early investment in applications which were, up to then, almost inconceivable was the trigger for continuous and consistent further developments in this area. While even well-known competitors were still hesitant to risk the switch to ASIC technology until well into the late 90s, SICK was then already using the third generation of its special semi-conductors.

SICK insight: Why are ASICs still relevant today?

Wilhelm Schürmann: The use of ASICs is now a matter of course. There are a variety of reasons for using these integrated switching circuits in photoelectric switches. On the one hand, the market’s demand for miniaturisation plays a major role, and then there are also cost and mass-production considerations. Simultaneously, however, general demands in industry have also increased sharply and are continuing to do so. In addition to the increased potential for interference in the area of EMC (e.g. because of mobile telephones, frequency converters, or other electromagnetic sources), greater demands are made on the optical side. Light beams from high and low frequency illumination, other sensors, or warning lamps and flashlights tax functionality just as much as chemical, mechanical or temperature effects. The introduction of chip technology allowed us to set new standards in photoelectric switch design. Those of note include high switching frequencies of up to 10 kHz, short response times, long scanning distances or ranges, and precise switching behaviour and repeatability. At the same time, the further developments in ASICs ensured that ambient temperatures of - 40°C to + 60°C, maximum immunity to impacts and vibrations, almost complete immunity to ambient light effects of all types, and electromagnetic compatibility are now no longer problematic.

SICK insight: What is special about the new chip technology as used, for example, in the WT 18-3 photoelectric proximity switch?

Wilhelm Schürmann: Another milestone has been achieved with the introduction of a new ASIC specially for photoelectric proximity switches with adjustable background and foreground suppression. Photoelectric proximity switches with this functionality have up to now required optical and mechanical regulation. In particular, the demand for wide adjustment ranges, high precision, very good black/white shift, and good adjustability and stability could only be achieved with good optics, a special receiver element, and an adjustable optical or mirror unit. While good optics remain an indispensable quality feature, the new chip generation replaces the adjustable mechanics with a new type of receiver array. Whereas maximum scanner precision could, in the past, only be achieved with a mechanical element in the mirror, it is now possible electronically. The evaluation chip offsets the signals and allows fine adjustment in several thousand steps.

SICK insight: What advantages does this offer users?

SICK insight: How does this intelligence express itself? Can the sensor learn? Can it ask and answer questions? Does it have an expanded horizon?

Wilhelm Schürmann: A clear answer to all these points: yes! The introduction of this new chip technology not only improves the desired efficiency of photoelectric proximity switches, but also allows the realisation of a communication capability right down to the level of standard sensors. While up to now only high-quality and more complex sensors or actuators have offered a direct fieldbus connection, with the integration of the new ASIC SICK has now created, for the first time, a fieldbus-enabled generation of photoelectric switches. Combined with a special connection module for fieldbus systems such as Profibus, a standard sensor becomes an intelligent sensor. The user is thus in a position to read in and out offset performance data, interference effects, or parameterisation data. This communication capability offers the user far-reaching possibilities for remote sensor diagnosis, maintenance and setup. If a sensor needs replacement, the new sensor can be supplied with stored data and setup via a parameter download. No qualified maintenance personnel are necessary for this; the mean time to repair is considerably reduced. Furthermore, the chip allows users to visualise their application, allowing rapid and optimised sensor setup. Plant availability is further improved with the help of this new technological opportunity, and downtimes are reduced.

SICK insight: With these features and advantages, the chip technology of the WT 18-3 will be one of the highlights at the Hanover Trade Fair. Thank you for this conversation.