This presentation contains the slides regarding the study of a plane table with all important topics.

1. PLANE TABLE SURVEY
Ansari Aqib Javed
150800106002

2. VADODARA INSTITUTE OF
ENGINEERING
SURVEYING(2130601)
PLANE TABLE SURVEY
Ansari Aqib Javed
(150800106002)
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3. Contents :
• Introduction
• Principle of plane table
• Setting up a plane table
• Orientation of a plane table
• Methods of plane table
• Adjustment of plane table
• Advantages & Disadvantages
• References
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4. Introduction
• Plane Tabling is a graphical method of surveying in
which the field work and plotting are done
simultaneously.
• Useful to fill in details between stations fixed by
theodolite traversing.
• Particularly adapted for small scale or medium scale
mapping in which great accuracy in detail is not
required.
• It is ideally suited to filling in details on a map already
prepared and available on the drawing sheet.
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5. PRINCIPLE OF PLANE TABLE
• The principle of plane table is PARALLELISM.
• It’s principle explains that the rays drawn from
stations to objects on paper are parallel to the
lines from the station to the objects on the
ground.
• The table is always placed at each of the
successive stations parallel to the position it
occupied at the starting position.
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6. Setting up the plane table
• The plane table should rest at a
convenient height ( about 1 meter ).
• The legs of the tripod to be spread
apart and firmly fixed on the ground in
such a way that the table should is
approximately level.
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7. Leveling the plane table
• In this operation, the table is made
truly horizontal.
• For small work the leveling can be
done by eye estimation, and for
accurate and large work leveling can
be done by a spirit level.
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8. Centering the plane table
• The table should be so placed over the
station on the ground that the point
plotted on the sheet corresponding to
the station occupied should be exactly
over the station on the ground. This
operation is known as the centering of
the table. This may be done using a U-
fork & Plumb-bob.
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9. Orientation of a plane table
• The operation of keeping the table at
each of the successive stations
parallel to the position which it
occupied at the first station is known
as orientation. It is necessary when
the instrument has to be set up at
more than one station.
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10. Orienting the plane table
• There are two methods of orienting a
plane table, they are :-
1. Orientation by magnetic needle
method.
2. Orientation by back-sighting method.
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11. ORIENTING BY MAGNETIC NEEDLE
• This method is used when it is not possible to bisect
the previous station from the new station. This
method is not much reliable and sometimes leads to
errors due to variations of magnetic field.
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12. ORIENTING BY BACKSIGHTING
• In this method the table is orientated by back
sighting through the ray which is drawn from
the previous station. This is the most accurate
and reliable method of orientation of plane
table.
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13. 12

14. METHODS OF PLANE TABLING
There are four methods of of
surveying with plane table :-
( a ) Radiation method.
( b ) Intersection method.
( c ) Traversing method.
( d ) Resection method.
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15. RADIATION METHOD
• In this method the objects are located
by radiating lines from the point, and
measuring the distance with chain or
tape with suitable scale.
• It is chiefly used for locating the details
from the station, which have been
established previously by other methods
triangulation, or traversing. 14

16. A
C
B
F
E
a
b
c
d
e
f
P
RADIATION METHOD
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17. INTERSECTION METHOD
• In this method the point is fixed on the plane
by the intersection of the rays drawn from
the two instrument stations.
• The line joining the stations is called Base
line.
• The method requires only the linear
measurements of this line.
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18. C
E
INTERSECTION METHOD
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19. TRAVERSING METHOD
• This is similar to that of Compass Survey or
Transit Traversing.
• It is used for running survey lines between
stations, which have been previously fixed by
other methods of survey, to locate the
topographic details.
• It is also suitable for the survey of roads, rivers,
etc.
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20. C
TRAVERSING METHOD
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21. RESECTION METHOD
• This method is used for establishing the
instrument stations only.
• A Characteristic feature of this resection is that
the objective is to plot the station occupied by
the table on the sheet rather than obtaining
other station or plotting the details.
• After fixing the stations, details are located either by
radiation or intersection.
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22. A C
RESECTION METHOD
a c
B
a
b
c
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23. Adjustment of the Plane Table
• The surface of the board should be
perfectly plane.
• The vertical axis of the instrument is the
line through the centre of the ball and
socket arrangement or the levelling head
or any other arrangement provided.
When this axis is vertical, the plane of
the board should be horizontal.
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24. Advantages of Plane table
(i) It is most suitable for preparing small-
scale maps.
(ii) It is most rapid.
(iii) The field book is not necessary as
plotting is done in the field concurrently
with the field work, and hence the
mistakes in booking the field notes are
avoided.
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25. Advantages of Plane table
(iv) The plotted work can be compared to
the actual work.
(v) It is particularly advantageous in
magnetic areas where compass survey is
not reliable.
(vi) Less skill is required.
(vi) It is less costly.
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26. Disadvantages of Plane table
(i) There are several accessories to be
carried, and, therefore, they are
likely to be lost.
(ii)It is heavy, feels awkward to carry.
(iii)It is not suitable for work in a wet
climate.
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27. Disadvantages of Plane table
(iv) It is not intended for accurate
work.
(v) It can’t be plotted on a different
scale, because there is no field book
used.
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28. Errors in a plane table
• There are 3 types of errors in a plane
table :-
(i) Instrumental errors
(ii)Human errors
(iii)Plotting errors
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29. Errors in a plane table
• In brief we are quite aware of the
types of errors in a plane table, so let
us study about the precautions to be
taken care to avoid errors in a plane
table while surveying.
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30. Following precautions should be taken
(i) The table must be accurately oriented
once it is shifted.
(ii) The alidade should be correctly centred
on the station point on paper.
(i) The expansion and contraction of paper
should be taken care off.
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31. (iv) The table should accurately centred.
(v) The board should be horizontal.
(vi) The objects should be accurately
sighted.
(vii) The rays should be accurately drawn
through the station points
Following precautions should be taken
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32. References :
• Surveying and Levelling by N.N. BASAK
• engineeringcivil.yolasite.com
• ustudy.in/sites
• Studprojwin14.in
THANK YOU
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