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Levels
Published in Leonid Nadolinets, Eugene Levin, Daulet Akhmedov, Surveying Instruments and Technology, 2017
Leonid Nadolinets, Eugene Levin, Daulet Akhmedov
A laser level is a device that creates either a visible laser line or plane, perpendicular to the plumb line. A laser level consists of the laser module and a leveling mechanism. The red laser module (Figure 2.27) has a laser light source (a red laser diode) and a condenser lens. The laser diode emits a divergence beam that becomes parallel when it passes through the condenser lens. The laser-emitting crystal must be accurately sets within the condenser lens’s focus. The laser crystal is placed on a heat sink next to the controlling photodiode. The principle of laser crystal operation is covered in Chapter 4. Now we should note that laser light power strongly depends on the crystal temperature. In order to minimize this dependence a laser driver with feedback control is used. The laser crystal emits light in opposite ways. Luminous power from the opposite side of the crystal enters the integrated photodiode. The photodiode signal depends on the laser’s luminous power. The signal enters the laser driver’s input. The amplified signal controls the power regulator so that the laser’s luminous power is stable. The luminous power from the laser crystal’s front side looks like a prolate ellipse. The condenser lens’s diameter overlaps only the central zone of this ellipse where a majority of the luminous power is concentrated. The laser beam from the condenser output can be directly applied or be transformed into a laser plane by the means of the cylindrical lens (Figure 2.27).
Force-System Resultants and Equilibrium
Published in Richard C. Dorf, The Engineering Handbook, 2018
A laser level uses a laser beam directed at a spinning optical reflector. The reflector is oriented so that the rotating laser beam sweeps out a horizontal reference plane. The level rod is equipped with a sensor to detect the rotating beam. By sliding the detector on the rod, a vertical reading can be obtained at the rod point. Laser levels are especially useful on construction sites. The spinning optics can also be oriented to produce a vertical reference plane.
Electrical Installation Methocs, Procecures And Recuirements
Published in Peter Roberts, Electrical Installation Work, 2017
There are modern devices which make finding levels much easier and more accurate. Laser levels fire lasers to establish room area as well as certain points along vertical and horizontal planes. A laser level will effectively self-level, but does require the user to carry out a pre-use check to ensure that the device remains in calibration.
Irrigated agriculture: more than ‘big water’ and ‘accountants will [not] save the world’
Published in Water International, 2022
● It is relatively easy for a water accounting person to advise how to improve irrigation systems when reproducing advice from internet-based sources. Over the years, many people (ecologists, economists, civil engineers, agronomists, etc.) have told me what constitutes better irrigation, despite no sign they have managed or systematically researched irrigation performance. Recommendations tend to be: line canals; irrigate at night; add soil moisture measurement; instal drip irrigation; laser-level fields; fix leaks; meter canal flows; train farmers on soil and water management; and create water user groups. It is not that these are individually wrong, but what troubles me is how they are dropped into the discussion. To me these shibboleths reveal that the adviser knows little about irrigation. There is no commensurate sense of how to think about these solutions such as: what the baseline performance might be; how effective they might be (for different purposes); their cost and who bears this; in what order of priority; their ‘system’ fit (to each other and to the local situation); how farmers might use and own these technologies or have equivalent solutions and different priorities;8 or that many ‘design-manageability’ reforms never get mentioned such as the density of canal network per hectare, retrofitting of manageable hardware or how to design-in the water duty down to a tertiary scale (Lankford, 1992; Lankford & Gowing, 1998). And it appears there is little awareness that there is a debate (still incomplete in my view) on irrigation manageability (Horst, 1999; Plusquellec, 2002; Plusquellec et al., 1994).
The effect of bogie track and forwarder design on rut formation in a peatland
Published in International Journal of Forest Engineering, 2021
Jari Ala-Ilomäki, Harri Lindeman, Blas Mola-Yudego, Robert Prinz, Kari Väätäinen, Bruce Talbot, Johanna Routa
Each machine was randomly allocated to a specific study trail pair, each consisting of a straight and a curved trail. Each machine conducted three to four passes on each trail. Rut depth was measured manually with a horizontal laser level and a surveyor’s measuring rod at three points (1.25 m, 2.50 m and 3.75 m) on each 5 m segment of the study plot on the straight trails and at seven points (2 m intervals) on the curved trails. Measuring points were marked with spray paint in the wheel track on the peat surface to enhance consistency in measurement location accuracy during the passes. Rut depth was measured at the deepest point of the rut, which was usually a track shoe depression in peat.
Development of all-in-one attachment-based PHC pile head cutting robot
Published in Journal of Asian Architecture and Building Engineering, 2019
Dong-Jun Yeom, Yesul Park, Young-Suk Kim, Jung-Yeol Kim
The sensing unit was designed to help automatically recognize where a PHC pile is to be cut during the PHC pile head cutting process. The core technologies applied are a laser level (LP510, Sokkia 2019) and an optical receiver (LR300; Sokkia 2019). The sensing unit (Figure 5) was developed such that the optical receiver detects the laser beam transmitted by the laser level and generates a beeping sound, allowing the operator to determine where to cut either by recognizing the interval between the beeps or through sensing data displayed on a small liquid-crystal display monitor mounted inside the cabin.