What is resection method of plane table surveying?
Resection is a method of plane table surveying in which location of a plane table is unknown. Location of a plane table is determined by looking it to known points.
What are the different method of plane tabling?
There are mainly four methods of plane table surveying, radiation, intersection or triangulation, traversing, and resection.
What is the purpose of conducting the resection method in the plane table surveying?
What is the purpose of conducting the resection method in the plane table surveying? To determine the location of the instrument. To plot the details. To survey hilly region.
What is the resection method?
In surveying, free stationing (also known as resection) is a method of determining a location of one unknown point in relation to known points. The instrument can be freely positioned so that all survey points are at a suitable sight from the instrument.
What is the principle of plane tabling?
The principle of plane tabling is parallelism means “All the rays drawn through various details should pass through the survey station”. Introduction: Plane table surveying is a graphical method of survey in which the field observations and plotting are done simultaneously.
What is the another name of Bessel’s method?
Bessel function, also called cylinder function, any of a set of mathematical functions systematically derived around 1817 by the German astronomer Friedrich Wilhelm Bessel during an investigation of solutions of one of Kepler’s equations of planetary motion.
What is the two point problem?
Two points problems: Location of the position on the plan, of the station occupied by the plane table by means of observations to two well-defined points whose positions have been previously plotted on the plan.
What is the difference between intersection and resection?
In resection, the one point with unknown coordinates is occupied and sightings are taken to the known points; in intersection, the two points with known coordinates are occupied and sightings are taken to the unknown point.
Why is ranging done?
When the line to be measured has a smaller length compared to the chain, then the measurement goes smooth. If the length of the line is greater, the survey lines have to be divided by certain intermediate points, before conducting the chaining process. This process is called ranging.
How many ranging rods are required to range a line?
Minimum 3 numbers of ranging rods are required for a ranging a line in direct ranging.
Which is the radiation method of plane tabling?
(1) Radiation method of plane tabling: In this method of plain table survey, the plane table is set up at only one station, and various points are located by radiating (drawing) a ray from the instrument station to each of the points, and plotting to scale along the ray the distance measured from the station to the point is sighted.
How are the resectors used for plane tabling?
The resectors Aa and Bb [Fig. 14.10] are drawn to locate ‘p’ the plotted position of station point P. This method gives satisfactory results, if the area is not influenced by local attractions. It is used for small scale mapping only.
Which is the correct method for plane tabling?
Figure 14.9 shows a scheme of plane table survey of closed area. This method can be used for open traverses also. This method is just opposite to the method of intersection. In the method of intersection, the plotted position of stations are known and the plotted position of objects are obtained by intersection.
How is the tracing method used in plane table surveying?
Tracing Method in Plane Table Surveying In the tracing method, the plane table is located at a point from where three points are visible. The table is oriented with respect to the plotted lines of those three points. Place the tracing paper on the drawing sheet and again sight the three points and plot the radiating lines.