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A few applications with laser systems

  • Laser distance measurement
  • Laser thickness measurement & control
  • Laser Steel slab detection and positioning
  • Laser Metal Slab Scalping
  • Laser Level measurement & control
  • Narrow space level measurement with Laser
  • Laser Crane collision avoidance
  • Ship Docking/berthing/mooring with laser assistance
  • Plane Docking with lasers
  • Measuring bridge height
  • Laser Face profiling
  • Profiling precious stones
  • Log position (wood industry)


The steel industry demands accurate measuring equipment to be used under difficult circumstances.

The environment is harsh, with high dust content and hot temperatures. The targets, hot metal, can be especially difficult because they radiate glowing light at elevated temperatures.

600 series is especially designed to measure to glowing targets. Most sensors used within this industry are equipped with 600’s optional filter and high power laser option.

Dimensions are captured with either single or multiple sensors. Thickness measurements are achieved with the use of two opposing sensors and a standard, PC computer.

Dimensional Profile of Steel Bar Using 2D Laser Scanners
Multiple laser scanners can measure surface angles and widths of cold-rolled steel. Each sensor captures portions of the cross-sectional profile.

Steel Shape Scanning Using 2D Laser Scanners
Overhead laser scanners capture width and thickness profiles of large pieces of steel as they are conveyed beneath a scan plane. The encoder position of the conveyor is fed into the laser scanners and 3D images of the sheets can be created for optimization programs.

Weld Seam Inspection Using 2D Laser Scanners. 
Laser Scanners profile the cross section of a running weld joint. This profile data goes through software algorithms to determine pass / fail criteria.

Rubber sheet thickness
Laser sensors measuring thickness of rubber in calendering operation

A large international rubber conveyor belt manufacturer uses model 600 laser displacement sensors to measure the thickness of black rubber sheet in a calendering process. After a one-month trial period, the 600-4 sensor model was chosen to replace other equipment which failed to meet accuracy requirements. Model 600 sensor is extremely durable and met the environmental requirements for this industrial application.

During calendering and rubber processing, the surface of the rubber sheet is very shiny and very black, creating conditions where little light can be reflected. These are often the most challenging conditions for optical measurement sensor. We installed an upgraded laser diode in model 600-4, bringing 5 mW of laser power (standard is 1 mW) to get a stronger return signal off the dark surface. The result was excellent sensitivity on the rubber sheet and fast measurement speeds.

This rubber manufacturer monitors the thickness measurements using four sensors positioned at the top, 140 mm (5.5 in.) from the sheet surface. The rubber sheet lays across a roll cylinder. The top of the roller is the reference (zero) surface for thickness measurements. The laser spots aim directly perpendicular to the sheet surface at four different points across the sheet width for this process where the material stretches between two rollers, so that the roller gap can be adjusted accordingly to produce the desired (consistent) sheet thickness.
Thickness measurement using two non-contact laser sensors

One of the most commonly-requested applications is thickness measurement using

two, opposing laser displacement sensors. The basic premise for this applicaiton is to aim sensors at the two sides of an object. If you know the readings of laser A and laser B and the fixed separation distance between the laser sensors, one can easily determine the thickness of an object. One must take important considerations to make sure that the laser is aimed perpendiculary to the surface. If the target material is moving, such as with continually-cased metals, it is necessary to synchronize the laser sensors so that they take distance samples at exactly the same time.
The above picture depicts a thickness measurement application where the manufacturer was producing plates of various contours and was currently measuring its thickness with manual callipers.  They chose two model 600 series sensors because of their superb accuracy and simple RS232 interfacing.

Triangulation laser sensors in a steel strip mill

The metals fabrication business is one of the oldest industries in the world. Large mills are automated, but some smaller mills still rely on hand-held micrometers to gage metal thickness. Model 200 laser measurement sensors are ideal for measuring steel strip thickness to fine resolutions. Steel passes between two opposing non-contact laser sensors. A computer or PLC receives the sensors' output and calculates a resultant material thickness based on a simple mathematical formula that takes into consideration the separation distance of the two sensors.

The limit swithces on model 200 sensors can be used to detect the location of a lap welds where two strips are joined.

The CMOS detector in model 200 allows the sensor to accurately measure to a variety of colors, including dark steel.

Postal automation using laser measuring devices

Industrial automation is widespread in the letter and parcel handling centers around the world. Sensors are commonly used to detect and measure pieces of mail at blistering speeds. Integrators of Postal Automation systems use the 200 series of laser sensors for counting individual flat packs in long stacks.

Series 200 novel sensor design is well suited to measuring to paper and cardstock materials of different colors. As the stacks of envelopes pass beneath the laser measuring sensor, the laser spot traverses the height profile. Software algorithms count each piece of mail.

The 200 series has a robust design can easily integrate into OEM systems because of its simple power and data interface requirements.

Laser sensors used for road profiling
Road Profiling has become a crucial practice for transportation departments throughout the world. US State DOT's (Departments of Transportation) are responsible for gathering statistical information on road surfaces including the longitudinal profile, mactrotextures, microtextures and roughness to determine coefficients of friction. The measuring tasks are especially challenging for most lasers because road surfaces present many dynamically-changing targets including tarmac, concrete, yellow striping, white striping, etc. Special lasers have been developed to maintain a consistent sampling rate over varying targets.

Versions of the 600 series have been produced for use as primary sensors for inertial profilers meeting ASTM Class 1 standards. The result is a model 600 with optics, electronics, and signal processing algorithms specifically for road profiling. Optics, electronics, and signal processing algorithms have been optimized for profiling. The result is an extremely accurate, cost-effective sensor for all surface types, vehicle speeds, and vibration, sunlight, and temperature conditions encountered in profilometry applications. As of March 2003 over a dozen road profiling sensors have been in service for more than a year with no field service required.

Overhead crane and lift application for  series 1000 laser distance sensor.

An overhead crane lifts aerospace components in a test cell.

Monitoring the position of trollies and hoists on bridge cranes in busy seaports requires accurate distance measurements afforded by the model 1000 laser distance sensor.

Cement and mineral industries use laser rangefinders

Profiling rotary kilns for shape and runout
The series 4000 laser rangefinder has unique benefits to certain applicaitons that can not be met with other products. Some engineers specify high speed sampling and high accuracy. For these requirements, we offer the 4000-LIR laser rangefinder.

The 4000 measures to 16.5 meters (54 feet) with 2.5 mm (0.1") accuracy to speeds of 770 Hz with RS232 output. Using an optional interface card, the distance measuring device can output 200,000 Hz.

Several equipment providers to the cement and minerals industries demand the series 4000 for a very special application. They affix the  distance laser meters to a tripod and aim it at a rotary kiln. As the large tube turns, they capture its profile to a computer. Back at the office, they re-create the shape of the kiln and diagnose runout and potential shape bulging problems.

Because of the dark colors of the exterior shell, the fast rotational speed, outdoor lighting conditions and long data transmission distances, the best solution was the series 4000 laser rangefinder with a 20 mW infrared laser diode and an optical bandpass filter.

In a similar applicaiton, engineers measure the position and vibration of steel connecting collars on clinker kilns.

Wing Profile Measurement Using 2D Laser Scanner
2D laser scanners are used to capture running profiles of airplane wings, turbine blades or helicopter blades.