Plane Table: The plane table is a flat drawing board that is mounted on a tripod. It is typically made of wood or metal, and is designed to be sturdy and stable. The surface of the plane table is usually covered with a sheet of white paper, which can be easily replaced as needed.
Alidade: The alidade is a sighting device used to measure angles between points on the terrain. The alidade typically consists of a sighting mechanism, such as a telescope, and a protractor for measuring angles. The sighting mechanism allows the surveyor to take precise readings of the angles between different points on the terrain, which are then transferred to the plane table.
Tripod: The tripod is a three-legged stand that holds the plane table in a fixed position. It is designed to be stable and sturdy, and is typically made of metal or other strong materials.
Spirit Level: The spirit level is a device used to ensure that the plane table is level. This is critical for accurate readings, as an unevenly mounted plane table can cause errors in the measurements. The spirit level is placed on the plane table, and the surveyor uses it to make adjustments to the tripod until the plane table is level.
Scale: The scale is a measuring tool used to determine the correct scale of the drawings made on the plane table. Scales are usually marked in units of length, such as centimeters or inches, and are used to determine the correct size of objects in the survey area.
Pencils and drawing materials: Pencils and other drawing materials, such as charcoal or colored pencils, are used to make sketches and drawings on the plane table. These sketches and drawings are used to create a representation of the terrain being surveyed.
Ruler or scale bar: The ruler or scale bar is a measuring tool used to determine distances on the plane table. This tool is typically used in conjunction with the scale to determine the correct size of objects in the survey area.
In summary, these are the main instruments used in Plane Table Surveying, and they work together to allow the surveyor to take precise measurements and make accurate drawings of the terrain being surveyed. Proper use and maintenance of these instruments can help to ensure that Plane Table Surveying continues to be a valuable and accurate method of surveying.
0 Comments