A global manufacturer of self-contained drill rigs uses the AccuRange 1000 laser distance sensor to automatically gage the depth of drilled holes. Their drill rigs are equipped with powerful down-the-hole hammers for high-capacity rock drilling in quarries, opencast mines and construction projects. The operator, sitting in a climate-controlled cabin, can know the exact hole depth on a digital console display.
The AR1000 has a nearly concentric optics path to measure down narrow holes. The range is up to 30 meters and the sensor will hold 2 mm of accuracy. Contact Acuity for more information.
Bridge Cranes Integrate Laser Distance Sensors at Steel Mills
Steel mills producing large coils of sheet stock store their inventory on the floors of huge warehouses. The large, heavy coils are picked and placed using overhead cranes, often referred to as bridge cranes. These cranes ride the length of the building along two, parallel rails. A hoist moves on the trolley and lowers a hook or other mechanical grabber to move objects. Operators control the crane’s movement via an overhead control cabin or by remote-control from on manufacturing floor.
Modern factories automate the pick and place of their inventory in 3D space by equipping their overhead cranes with multiple laser distance sensors. This automates the gross movements of the crane and minimizes the time to locate and move a particular piece of inventory. A common application is in steel mills, where building lengths often exceed 250 meters. The AccuRange 3000 sensor measures the position of the crane’s trolley along these longest stretches. Side-to-side position and the hoist’s vertical position are accurately monitored by AccuRange 1000 laser distance sensors. These models are well-suited for industrial environments and interface directly with system PLC’s using analog and serial outputs. Today’s mills retrofit manual-control cranes with automation systems employing laser positioning sensors.
Acuity manufactures and sells the AccuRange™ brand of laser rangefinders, which use time-of-flight measurement principles to detect a target’s position or displacement. The device models offer a variety of ranges, accuracies and speeds to suit a variety of industrial automation projects.
For more information about this or similar application, contact Acuity.
In 2006, the City of Minneapolis commissioned a permanent public artwork at the Minneapolis Public Library. Built into the structure of the two glass elevator cabs in Library Hall, “Four Stories” displays the titles of recently checked-out books in large, illuminated text as the elevators move between floors.
The design integrators selected the Acuity laser rangefinders to monitor the position of the elevator and hence control the scroll position of the illuminated text. The laser rangefinders were installed in base of the elevator shaft and aimed upward to a target affixed to the bottom of the elevator cart. Sampling at 100 Hz, the positional data was used in the software controlling the visual display. For more information, contact Acuity.
A manufacturer in Brazil designs and builds tanks and vessels for use in various chemical and petrochemical industries. The tanks built from carbon or stainless steels, are fabricated in sections and welded together in a final assembly. They are required to maintain strict dimensional tolerances for the pre and final assemblies. The company approached Acuity to assist in improving their dimensional measurement practices.
Manufacturers must control the dimensions of the fabricated
Current quality control tool - a wooden template the same shape as the endcap
The manufacturer currently verifies the shape and dimensions using manual methods. Operators use a tape measure to determine the diameter of the hemisphereical endcap. The resolution of this measurement technique is 1mm and the accuracy varies on the operator technique. They have no method for measuring the interior profile dimensions of the tank’s endcap. For quality verification, operators insert a large, wooden template into each vessel and attempt to assess its fit. They will look for gaps between the edge of the template and the surface of the vessel. The plywood template is subject to thermal and moisture-induced expansion and contraction. The templates require two operators.
The solution to the measurement challenge was to use a non-contact laser distance sensor to measure the interior surface of the end-cap from a central measurement axis. The rangefinder would be rotated 180°, measuring the distance from one edge, through the base and to the other edge. This would allow not only the diameter, but also the entire profile of the shape. This information could be transmitted to a computer for display and archiving.
The AR1000 laser distance sensor has a measurement resolution of 1mm and was successful in measuring all expected surfaces, including bright-ground steel, light oxidation, paint, oiled surfaces, black paint, gray paint, etc. The planned orientation of the sensor guaranteed a strong laser reflection off shiny surfaces.
The Boeing 787 Dreamliner is the first commercial aircraft built from lightweight composite materials. Like aluminum structure wings during their development, the composite wings undergo rigorous test. Among those tests, is the “wing up-bend test” which test the mechanical integrity the wing when being displaced upwards.
On March 28, loads were applied to the test unit to replicate 150 percent of the most extreme forces the airplane is ever expected to experience while in service. The wings were flexed upward by approximately 25 feet (7.6 meters) during the test and the fuselage was pressurized to 150 percent of its maximum normal operating condition. In evaluating the success criteria for the test, Boeing specialists have been poring over the thousands of data points collected during the test to ensure that all parts of the airplane performed as expected. “The airframe performed as designed and retained the required structural integrity. These results continue to validate the design of the 787 as we move toward certification,” explained Fancher.
Hanging from the end of each wing was an Acuity AR1000 laser distance sensor, mounted on a gimbal to ensure the laser would be pointed perpendicularly to the floor as the wing bent upwards. The AR1000 read the distance from the ends of the wings to the floor. Connected to each laser was a scoreboard display, showing the distance in large numerics that could be read from anywhere in the test area. The lasers can not be seen but the white target area on the floor beneath the wing tips is visible. That was how the 7.6 meter (25 foot) wing flexure was measured, +- 2mm.
Project M is a proposed project to land an operational humanoid robot on the moon in 1000 days (M is the Roman numeral for 1000). The humanoid (called a Robonaut) will travel to the moon on a small lander fueled by green propellants, liquid methane and liquid oxygen. It will perform a precision, autonomous landing, avoiding any hazards or obstacles on the surface. Upon landing, the robot will deploy and walk on the surface performing a multitude of tasks focused on demonstrating engineering tasks such as maintenance and construction; performing science of opportunity (i.e. using existing sensors on the robot or small science instruments); and simple student experiments.
As with most autonomous vehicle projects, the NASA RR-1 Lander requires many sensors to fully control its flight. Design engineers contacted Acuity for a solution to measure the altitude of their RR-1 Lander. The AR3000 Distance Sensor was proposed to measure the real-time height of the vehicle to 300 meters above the ground at high sampling speeds. View the integration of the laser rangefinder on the vehicle at the 3:00 minute mark of the project update video.
A system integrator in Croatia worked closely with a steel pipe manufacturer to develop a system for measuring the length during production. The clever solution incorporates an AR1000 laser distance sensor from Acuity to measure to the leading edge of the pipe during cutting. The high-speed saw blade serves as the Zero Point Reference during the cutting process. The pipe is stationary during cutting and gives a very stable reading.
A non-contact solution was required because the pipe is quite hot and still glowing orange. The laser spot is perfectly aligned to measure to the edge of the pipe, on the surface between the inner and outer diameters. The rangefinder is installed sufficiently far away from the heavy, moving pipe.
This steel pipe manufacturer plans to use this solution on all of its production lines in the future because it saves time and reduces worker exposure to the hot material.
For more information about this novel application of the laser distance sensor to measure pipe length, contact Acuity or Axium Europa d.o.o.
A zip-line consists of a pulley suspended on a cable mounted on an incline. It is designed to enable a user, propelled by gravity, to traverse from the top to the bottom of the inclined cable by holding on or attaching to the freely moving pulley. Zip-line tours are becoming popular vacation activities and ride managers often implement a high speed camera system to photograph riders during their decent.
Zip line photographs. Camera triggered by Acuity AR3000 rangefinder
One zip-line company (Xplor) has selected a high-speed, long-distance rangefinder to improve the timing of their photographs. The Acuity Distance Measurement Sensor (model AR3000) uses an eye-safe laser to track the position of moving targets. Accurate to within centimeters, the sensor takes distance samples every 0.5 milliseconds. The sensor device is configured to transmit a voltage output signal at a set alarm point location within the sensor’s 300 meter range. This output signal triggers the high-speed camera to photograph the rider at exactly the right moment.
Contact Acuity for more information about high-speed distance rangefinders and to discuss your unique sensor applications.
A faculty member of the Agricultural Sciences Department at Aarhus University (Germany) uses a laser rangefinder in the Mobilas mobile canopy sensor.
Precision agriculture requires reliable technology to acquire accurate information on crop conditions. Based on this information, the amount of fertilizers and pesticides for the site-specific crop management can be optimized. Farmers turn to university research departments to assist in developing technology to help acquire this data.
Farming tractor with laser rangefinder from Acuity
Laser range measurements are made at a 50 degree off perpendicular angle. From 1024 range measurements canopy height and leaf area index (LAI) are calculated. The customer chose the AR4000 laser rangefinders from Acuity because of their high sampling rates and their ability to accurately measure in sunlit conditions. The AR4000 samples up to 50 KHz using an external high speed interface card that resides in a PC computer in the cab of the tractor.
A new manufacturer of foundation testing equipment developed the PileTrac Pile Set Monitor (PSM). The system improves the process for collecting and reporting pile set measurements during pile driving. Pile set is used to confirm pile driving requirements and for input into signal matching programs for prediction of static pile capacity.
Conventional pile set measurements (typically at end-of-initial drive or beginning of re-strike) are performed by placing a worker in close proximity to the pile and manually marking the pile between hammer impacts (see companion video). Conventional pile set measurement are often inaccurate with missed blows and/or marks or marks made without a fixed reference point.
The PileTrac Pile Set Monitor consists of an Acuity AR1000 laser rangefinder in combination with data acquisition and processing software to collect pile set data. The rangefinder is affixed to a stationary base and measures the The automated equipment is set up prior to starting of the hammer and does not require the use of manual recording methods.
Since data is acquired at a rate much faster than the hammer impacts, stable distance readings between the pile mounted target and ground mounted laser are achieved between hammer impacts which permits accurate computation of permanent set and blow count.
The PSM may be used for many other engineering and construction applications such as bridge deck deflection monitoring, confirmation of rod penetration during SPT sampling or for distance or displacement measurements to confirm performance of foundations or structural systems under loading.
For more information about this application or to get a quotation on a Piletrac PSM system, please contact Piletrac.
The manufacturer currently verifies the shape and dimensions using manual methods. Operators use a tape measure to determine the diameter of the hemisphereical endcap. The resolution of this measurement technique is 1mm and the accuracy varies on the operator technique. They have no method for measuring the interior profile dimensions of the tank’s endcap. For quality verification, operators insert a large, wooden template into each vessel and attempt to assess its fit. They will look for gaps between the edge of the template and the surface of the vessel. The plywood template is subject to thermal and moisture-induced expansion and contraction. The templates require two operators.
The solution to the measurement challenge was to use a non-contact laser distance sensor to measure the interior surface of the end-cap from a central measurement axis. The rangefinder would be rotated 180°, measuring the distance from one edge, through the base and to the other edge. This would allow not only the diameter, but also the entire profile of the shape. This information could be transmitted to a computer for display and archiving.
Posted on January 9th, 2012 by admin
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