Clinometer

Clinometer (forestry) From Wikipedia, the free encyclopedia turn out to navigation, search A in in inclinometer utilise in forestry The clinometer, known in many fields as an inclinometer, is a common tool used in forestry to musical rhythm slope, vertical angles, and in combination with distance barroomments overhead railway change or tree statures. How it works A forester use a clinometer makes use of basic trigonometry. First the beholder legal communitys a straight-line distance D from some observation point O to the object. Then, victimisation the clinometer, the observer measures the angle a between O and the illuminate of the object.Then the observer does the equivalent for the angle b between O and the bottom of the object. Multiplying D by the tangent of a gives the height of the object above the observer, and by the tangent of b the depth of the object below the observer. Adding the two of run-in gives the total height (H) of the object, in the same units as D. 1 Note that since times is distributive it is equally valid to add the tangents of the angles and then multiply them by D A = tan a B = tan b H = (A ? D) + (B ? D) = (A + B) ? D Note also that both angles should be irrefutable numbers (i. . ignore any minus sign on the clinometers scale). Units of measure There argon typically three different units of measure that roll in the hay be marked on a clinometer degrees, percent, and topo. When buying a clinometer it is important to make sure it is calibrated to units suitable for the think use.Tree height measurement Tree height measurement The forester stands at a fixed distance from the base of the tree. The most common distances in the United States are 50feet (15. 24 m), 66feet (20. 12 m), and ascorbic acidfeet (30. 48 m). 2 To obtain accurate cultivations it is best to use taped deliberate distance instead of paced distances. For the most accurate evinceings it is best to use a distance that is not less than the height of the tree being thrifty. 3, that is, that the clinometer go forth measure an angle less than 45 (100%). The observer sights to the top of tree, if total height is the desired measurement. If the desired measurement is sellable height that is, the height p retinal roducing timber that raise be sold the observer sights to a point on the tree above which no more merchantable timber is found.The observer then measures to the bottom of the tree, takes the tangents and multiples them by the distance, and adds the two figures together. This will be the height of the tree. The observer must always measure a leaning tree so that the tree is leaning to the left or right. Measurements should never be taken with the tree leaning toward or outside(a) from the observer because this will affect their accuracy because of foreshortening. Slope measurement mensuration slope with a clinometerThe clinometer is also commonly used by foresters to obtain the percent slope of terrain. This measure ment is based on the same trigonometric principles described above. Slope measurements, however, require that both observer and fag be a constant height above the ground and then a range pole or height of measurement (HI) receive is often used in slope measurements. The Clinometer The clinometer is an opthalmic device for measuring rod natural line of longitude angles above horizontal. The most common instruments of this character currently used are compass-clinometers from Suunto or Silva.Compass clinometers are fundamentally sightly magnetic compasses held with their plane vertical so that a plummet or its equivalent can point to the elevation of the sight line. A give out clinometer (I believe) is the Abney hand spirit take or clinometer, where the object spy and the train bubble can be seen simultaneously, so that the proponent can be set accurately. An Abney clinometer is shown in the photograph. A spirit level is so-called because it contains alcohol in a tube of l arge radius, in which the bubble moves to the highest point.Spirit levels are used for accurate surveying, although automatic levels that go stake to the principle of the plummet are now frequently found, and are wakeful to use. The Abney clinometer has a sighting tube with an angle scale get hold ofing from -90 to +90, and a spirit level with a Vernier index that can be moved along the scale while the user looks through the sighting tube. A small mirror and lens makes the level bubble visible in the field of view. When the object is aligned with the crosshair in the sighting tube, the spirit level is rotated so that the bubble is bisected by the crosshair, as illustrated in the diagram.Then, the elevation of the line of sight can be read off on the scale. The Vernier can be read to 10&8242, but it requires a magnifier to do this. The clinometer can read soft and accurately angles of elevation that would be very difficult to measure in any other simple and inexpensive way. A pa ssably common use of a clinometer is to measure the height of trees, which is easily done. A point should be marked with a stake as far from the centre of the trunk of the tree as its estimated height, so that the elevation angle is about 45, which gives the best geometry. This distance D is measured with a tape. The observer then stands over the stake and sights the top of the tree, determination its elevation angle ?. The height H of the tree is then H = D tan ? + HI, where HI, the height of instrument, is the height of the observers eye. All this is illustrated in the diagram. A useful accessory is a levelling rod, which can be home-made at micro expense. Since the clinometer has no powerful telescope, the reading of the rod must be evident from a distance if you use it as a self-reading rod.Alternatively, if you engage a rodperson, she can stand by the rod and move a finger or other marker up and down in response to your signals, then measure the distance with a tape. A self- reading rod can be made from a 1&8243 x 4&8243 x 10&8242 choice pine board available at Home Depot. A bold pattern that can be estimated to a few centimetres can then be applied by stencil and matte black spray paint. Two examples are shown at the right. modify can also be used to make distinctions. The determination of the rest in elevation of two points is called levelling, and can be carried out with the clinometer set at 0.The place where you stand with the level is called a bend point, TP. Your rodperson holds the rod on the first point, and you make a backsight, BS, by reading the rod. The reading is the HI above the first point. Now the rod is held on the second point, and a foresight, FS, is taken. Foresights and backsights should be roughly equal in distance. The difference in elevation of the two points is BS FS. This procedure is illustrated at the left. If both points cannot conveniently be viewed from one TP, a chain of turning points is used, with an intermediate e levation between each one.The difference in elevation is the sum of the backsights less the sum of the foresights. If the sights are short, such as those that are practical with the clinometer, the curvature of the earth will be taken into eyeshade automatically. Clinometer Clinometers are measuring devices that may be used in several different professions. Also known as an inclinometer, the essential subprogram of the device is to determine accurate measurements as they relate to sloping, height and distance.The clinometer is often used in the profession of meteorology, as well as in forestry and surveying. One of the most common applications of the clinometer has to do with measuring angles as they relate to the slope of natural formations or buildings and other clement construction projects. The idea is to measure the angle with an eye toward identifying any enumerate of slope, with respect to the gravity that is involved. The clinometer may be used to measure both inclines a nd declines, based on the perspective of the individual calculating the measurements.