MEASUREMENT OF POSITIONING ACCURACY IN 1 AXIS

Transcription

1 LS 100 MEASUREMENT OF POSITIONING ACCURACY IN 1 AXIS This is the basic configuration. It is designed for positional calibrations of machine tools, coordinate measuring machines, universal length meters and for general measurements of displacement. Safety warning symbol for the class 2 Laser Products Laser, Interface, Linear Optics, Sensors Calibration of a machine tool Linear Optics Beamsplitter and 2 Reflectors Interface Air Sensor Material Temperature Sensor Wireless Remote Control

2 1) LS 10.3 STABILIZED LASER WITH RECEIVER 2) LS INTERFACE UNIT 3) LS 20.1 POLARIZATION BEAMSPLITTER 4) LS 21.1 RETROREFLECTOR (2 pieces) 5) LS 51 MOUNTING SET not shown in the picture 6) LS 60.1 TRIPOD WITH ADJUSTABLE TABLE 7) LS 75.1 AIR SENSOR (p a, t a, φ a ) 8) LS 75.2 MATERIAL TEMPERATURE SENSOR (t m ) 9) LS 31.1 REMOTE CONTROL 10) LS CABLE A 11) LS CABLE B NOTE: Standard LS 100 Configuration includes 1 Air Sensor LS 75.1 and 2 Material Temperature Sensors LS Further Sensors and Remote Control LS 31.1 can be added.

3 DESCRIPTION OF LS 100 UNITS LASER LS 10.3 Laser wavelength accuracy 0.02 ppm, 36 month warranty Wavelength accuracy 0.03 ppm has been verified for lasers tested through 10 years 1). This test included also laser from the initial series with specified accuracy 0.05 ppm No waiting for warm-up of the laser. Laser is stabilized immediately when it is switched on Laser tube is filled with a mixture of He 3, Ne 20 and Ne 22 isotopes 2). In this way laser wavelength is not influenced for example by disturbing back reflections of the laser light. These back reflections can influence the measurement accuracy with other type of lasers Innovative design increased considerably reliability and shock immunity of the laser Unique design of the laser tube allows simple refilling after about 10 years of function if necessary Laser tube LS 10 used in Laser LS 10.3 Limtek is producing laser tubes with the mentioned features from 1989 Laser power < 1 mw (Safety Class 2 Laser Product) 1) Petru F., Vesela Z. Single frequency HeNe laser with a central maximum of output power, Optics Commun. 96 (1993) ) Petru F. et al Iodine stabilized He-Ne lasers at 633 nm for testing the vacuum wavelength of laser interferometers, JMO 1 (2003) Working conditions Environmental temperature C, relative air humidity 0-95% (non-condensing), barometric pressure kpa. Storage and transport conditions Temperature should be kept within the range from C to C, relative air humidity 0-95% (non-condensing)

4 INTERFACE LS LS Interface Unit evaluates the quadrature (sin/cos) signal from the laser LS It displays numerical values of displacements, angles or elevations depending on the selected measurement task. The unit is equipped with a telemetric receiver for collecting data from wireless sensors of atmospheric parameters (pressure, temperature and humidity) and from temperature sensors situated on the measured object. The received values are used for compensation of the laser wavelength influenced by the air pressure, temperature and humidity and for compensation of temperature dilatation of the measured object. Communication with a host computer system is provided by Ethernet over Cat 5 cable, USB Type 1 or Type 2 or wireless IEEE b WiFi. In this way it is possible to obtain current values of the measured quantities and set the optional parameters for the measurement task. These parameters include the method of laser wavelength compensation, temperature coefficient of the measured material etc. Communication is based on the standard TCP/IP protocol. This allows an easy integration of the LS unit into the local network. Messages Displayed Mode (length, angle, camber) Sign (+, -) Gain of the laser beam detector Laser wavelength Temperature, pressure and humidity of air Temperature of the material Expansion coefficient of the material Compensation (ON or OFF) Relative laser beam intensity Current value of the measured quantity

5 COMPENSATION SENSORS LS 75 Sensors LS 75 measure temperature, atmospheric pressure and humidity and transmit the data wirelessly on distance of several tens of meters. For permanent applications cables can be used as well. Sensors are designed to monitor ambient environment and/or temperature of the measured machines and instruments. The measured values of air temperature, pressure and humidity are used for calculation of the air refraction index according to the Edlén s formula. Two models are available: Air Sensor LS 75.1 is equipped with sensors of air temperature, pressure and humidity Material Temperature Sensor LS 75.2 is equipped with sensor of surface temperature with possibility of magnetic fixation Sensors are designed as autonomous instruments with battery power supply. In the active state the measured values are periodically scanned and sent to the Interface by radio communication channel. Identification number of the sensor is sent together with the data. In this way recognition of each simultaneously active sensor is guarantied. The Interface LS receives the measured data. Sensors are equipped with a miniature connector for cable. This could be convenient if the sensors are mounted in a machine permanently. Also in this case more than 10 sensors can be used simultaneously. Wireless Air Sensor LS 75.1 Wireless material temperature sensor LS 75.2

6 Sensors - Technical Specification Temperature Range 0-40 C Absolute accuracy ±0.1 C Resolution <0.01 C Air Pressure Range kpa Absolute accuracy ±0.1 kpa Resolution 0.01 kpa Air Humidity Range 0-95 %RH Absolute accuracy ±3 %RH Resolution 0.03 %RH RF communication channel Frequency 433 MHz Aerial connector SMA female Distance range >50 m in open space >15 m in buildings Scan interval 5 s Power supply 2 x AAA alkaline batteries Operation time >500 h Weight (incl. batteries) 150 g Dimension 105x58x20 mm Sensors LS 75 together with USB receiver LS 75.3 can be used also as an independent weather station. Details are in the section LS 140 Temperature and air sensors. WIRELESS REMOTE CONTROL LS 31.1

7 USING LMS LASER MEASUREMENT SYSTEM Connect the LS Interface Unit and the LS 10.3 Laser with cables A and B. Depending on the interface chosen for communications between the LS Interface Unit and the host computer (Ethernet, USB or WiFi) attach the appropriate cable or screw antenna to WiFi connector. Screw the aerial for communication with sensors or connect the cables if the sensors are to be mounted in the machine permanently. Attach the Power Cable to the LS Interface Unit power socket. Turn the LS Interface Unit on by rotating the key switch one-quarter turn clockwise. Allow one minute for the Interface Unit to initialize. Start the LMS program by double-clicking the LMS desktop icon LMS Software Starting Menu with options: Positioning accuracy Small angle Way straightness Flatness

8 Measurement of positioning accuracy Graph shows result of a positioning calibration

9 Machine tool calibration with a Limtek laser interferometer LS 100 SPECIFICATIONS Linear Measurement Measurement Range 0 40 m Resolution 1.25 nm (λ/512) Max. velocity 1 m/s Accuracy with LS 75 wireless compensation unit is 0,7 µm/m in temperature range 0-40 C Calibration Software VDI 3441 VDI 2617 ISO NMTBA Compensation Machine Tool Controllers Sinumeric 840C/810C Sinumeric 840D/810D/802D/802C/802S Heidenhain 426/430 Heidenhain 415 Fanuc 16i/18i/21i

10 Contacts Tel:/ Production facility: LIMTEK Laser Division SAR s.r.o. Horní Lhota Blansko Czech Republic HQ: LIMTEK Laser Division SAR, s.r.o. Brněnská Kuřim Czech Republic ID VAT ID CZ Bank Details: IBAN Account Number: CZ Bank: Raiffeisenbank a.s., Prague, Czech republic. SWIFT: RZBCCZPP Account owner: SAR, s.r.o. Brnenska Kurim Czech Republic