Posted to News on 28th Jun 2011, 21:59
Optical linear measurement sensor with improved performance
Sick (UK) is launching the OLM200 optical linear measurement sensor for high-performance materials handling applications. The enhanced positioning sensor, which delivers increased accuracy, speed and repeatability, uses a barcode tape to provide non-contact linear positioning on both curved and straight tracks. The sensor continually reads up to three barcodes to establish an absolute positional value, thereby ensuring optimal performance even if a barcode is missing or damaged.
The innovative new sensor, which is supported by additional plant control system connectivity, has high operating speeds of up to 10m/s, with non-contact linear positioning to 0.15mm, for greater repeatability and positional accuracy, enabling better space utilisation in automated picking lines.
Furthermore, the increased speed of the OLM200 can be utilised to achieve higher volume throughput, which makes it suitable for use in applications such as rail-mounted shuttles, overhead conveyors, rotary tables, turntables, slewing rings hoisting systems and robots, all commonly used in the automotive, textile and film industries.
Fieldbus communications
A Profibus DP interface enables connection to more complex distributed control systems. As well as diagnostic information, both position and speed can be communicated for enhanced system control.
Darren Pratt, the distance sensor product specialist at Sick (UK), comments: "The OLM200 illuminates the barcode using a red LED, and a CMOS array reads the illuminated barcode. Without moving parts, such as the mirrors used in conventional barcode scanners, the read head is highly reliable, even when mounted on a machine subject to high levels of vibration and shock.
"As no laser is required for the unit, there are no classification issues. In addition, the LED illumination has a life expectancy of almost twice the length of a good-quality laser diode. You can expect to get 100,000 hours of use from the OLM200, as opposed to the average 50,000 hours expected from a laser diode; it is therefore perhaps no surprise that we have had a great deal of interest in the OLM range."
Sick's OLM200 is designed for maximum performance and availability. Its high-resolution measurement and high output rate enables precise and fast positioning, while Speedcon connectors allow rapid installation. The system is extremely hard-wearing with a rugged metal housing for the sensor and a 100micron durable polyester material for the barcode tape, which has a tear strength of 150N/15mm.
Tough tape
The barcode tape is claimed to be impervious to most oils, greases, fuels, solvents and weak acids. The system also accommodates temperature fluctuations between -30 and + 60degC, so it is suitable for use in extreme temperatures such as cold stores and steel works.
To simplify installation, it is only necessary to fit the barcode tape where positional information is required. In case of damage, replacement barcode tape can be quickly created by downloading and printing the code from the Sick website.
With easy alignment, simple mounting and no need for continuous calibration, the OLM200 saves the end-user both time and money on installation and maintenance. Using Sick's SOPAS software, the optical linear measurement system is also easy to program and diagnose. The introduction of the OLM200 adds Profibus to the multiple output types already available in the OLM range, including SSI, RS422, RS485 and CANopen. Additional interface options will be added during 2011.
Contact Sick (UK) for more information about the OLM200 optical linear measurement sensor.
