DETAILED ANALYSIS OF PLANE TABLE
SUMIT VIKRAM SINGH
ROLL NO:-120107234, CIVIL 2ND YEAR, SEC- D
COURSE NAME:- PRINCIPLES OF SURVEYING
COURSE CODE:- CVL210
DEPARTMENT OF CIVIL ENGINEERING
SCHOOL OF ENGINEERING AND TECHNOLOGY
SHARDA UNIVERSITY, GREATER NOIDA, U.P, INDIA
CONTACT: - email@example.com
The main objective of this research paper is to present a deep and specified presentation on
plane table surveying. What, how and where is plane table surveying used is explained in
detail in these papers. A brief introduction followed by the history and plotting methods and
uses and benefits of this type of surveying have been discussed ahead. Also the three main
phases of plane table in the time has been discussed. Emphasis is given even to small details
regarding types and uses of alidades in plane table surveying. Subjects are supported with
good clear images in order for better understanding.
The main purpose of writing these papers was to provide a flexible, clear and detail
information on one of the oldest surveying methods in the world. Before the advancements in
civil engineering and the introduction of modern civil engineering instruments and
equipment’s, plane table surveying was the initial and base of surveying. This was one of the
widest used methods. A good systematic analysis is done on the topic ahead in these papers.
Plane table is a graphical method of surveying in which the field works and the plotting is
done simultaneously. It is particularly adopting in small mapping. Plane table surveying is
used for locating the field computation of area of field. It is particularly adapted for small or
medium scale mapping in which great accuracy in detail is not required.
A plane table (plain table prior to 1830) is a device used in surveying and related disciplines
to provide a solid and level surface on which to make field drawings, charts and maps. The
early use of the name plain table reflected its simplicity and plainness rather than its flatness.
Plane table surveying is based on the principle that lines drawn during plotting always lie
parallel to the corresponding lines actually present on the ground. For quick and approximate
surveying, when great precision and accuracy is not needed, plane table surveying techniques
is very suitable. It is particularly convenient for filling the details between the stations already
fixed and surveyed by more precise method of triangulation or theodolite traversing. For
small area surveys, plane table is recommended. The great advantage of this technique is that
field work and map plotting is achieved simultaneously by use of graphical surveying. The
principle used in plane table surveying is that an unknown point of interest can be established
by measuring its directions from known points.
The first known instrument for directly producing a drawing of a site was developed by
Johann Richter. He is also known as Johannes Praetorius, a Nuremberg mathematician, born
Thiscircular table, called atabula praetoriana,mensula praetorianaor Pretorian table, used
with a simple alidade and allowed a piece of paper to be slipped under the alidade
for drawing. Later the devices adopted a rectangular table and enhanced the type and features
of the alidade
THE ORIGIN OF ALIDADE
1. An indicator or a sighting apparatus on a plane table, used in angular measurement.
2. A topographic surveying and mapping instrument used for determining directions,
consisting of a telescope and attached parts. There are a number of common usages, the main
subject of this web page is the map making surveying instrument used on a table that has
been leveled. On ships an Alidade is used to measure the angle from the ship's longitudinal
axis to some target or targets, typically to helpdetermine the ships position relative to the
target(s). Large telescopes have an alidade system that’s used to point in azimuth. These were
used on a wooden table that had a drawing attached. The idea was to make a map while in the
field using stadia for distance to the rod.
The very early Alidades were just a ruler with sighting wires held in a frame at each
end. That was what was used on the Sketch Boards.
A compass can be used as an Alidade when a scale is aligned with the
North position. The Dietzgen Compass with square scale is in this category and you
can get a scale base for some models of the Brunton Com-Pro pocket transits
The K&E Early 1800s Alidade appears to be a transit instrument with a vertical angle
measuring vernier capability and probably with stadia hairs in the scope so that
distance can be manually computed for inclined shots. No compass as part of the
Figure: different type of alidades
THE EXPENSION OF THE PLANE TABLE
Plane table mapping is a subject that has received minimum attention over the years, but
it played a very important role in the history of surveying. The plane table dates to
approximately the beginning of the 17th century. Some of the first references to the plane
table are found in early survey textbooks. The early plane table was a mapping tool, as
opposed to the compass and chain that was a boundary tool. The early plane table dealt
mainly with planimetric features and not with vertical elevation. The use and development of
the plane table has gone through four distinct changes since about 1600. I will address each
one of these plane tables and its use.
PLANE TABLE CONSTRUCTION
Aplane table consists of a smooth table surface mounted on a sturdy base. The connection
between the table top and the base permits one to level the table precisely,
using bubblelevels, in a horizontal plane. The base, a tripod, is designed to support the table
over a specific point on land. By adjusting the length of the legs, one can bring the table level
regardless of the roughness of the terrain.
PHASES IN PLANE TABLE:
1.THE FIRST PHASE:-
Figure 1. The first alidade was a ruler or scale of brass with fold-down sights.
The first plane table consisted of wooden boards placed together to form a table about 14 x
11"mounted on a tripod. A paper or cardboard sheet was placed on top of this board.
The planimetric map or traverse was drawn on the paper. The alidade is the item that has
gone through the most changes. The first alidade was a ruler or scale of brass with fold-down
sights, about the same configuration as compass sights
2. SECOND PHASE:-
Figure 2. A 19th century plane table
The second phase brought about a name change from plain table to plane table. By the middle
to the end of the 19th century, the instrument became in shape and size the plane table most
surveyors would recognize (see Figure 2). The alidade now had a telescope. The table was
about2' square and was mounted on a tripod with an adjustable mount for leveling and
rotating the table to orientate to north. The alidade had a vertical circle to turn a vertical angle
and calculate the difference in elevation between points.
3.THIRD PHASE:- THE MODERN ERA
Figure 4. Plane table mapping in the field
Unfortunately-or fortunately-the total station with data collection made the plane table and
alidade into museum pieces. No article would be complete without a mention of the
surveyors who utilized plane table boards. There were only a few days each year suited for
plane table mapping. The weather needed to be warm but not hot; sweat dripping from your
face and hands could make amass of the paper drawing. The USGS used an umbrella over the
board when mapping. Surveyors also needed a day with very little wind. And the reflection of
the sun off the board would quickly turn your face into old shoe leather. In the winter, your
fingers would get stiff from the cold, making it very difficult to draw the map. Bending over
the board for eight hours each day without being able to lean on the table took a physical toll
on the back.
METHODS OF SURVEY:
USING PLANE TABLE AND ALIDADESURVEY
1. This is a method of survey that allows a surveyor to plot and create an accurate scale
drawing on site. The idea is to scale down the site to a size that fits onto the drawing board.
2. A plane table is a drawing board which is fixed to a tripod, leveled, and orientated. An
alidade is a sighting device used to observe the salient points of the site.
3. Have a good look at the site before you start the survey, time should be taken
to walk round and have a good look at the site or building that you are going to record. On
a building, the obvious features that you would want to record are the corners, door and
window openings, fireplaces. More subtle features that you would look out for are changes in
wall direction, straight joints, blocked doors or windows, crack slots, changes in the
stonework, changes in floor covering, byre drains.
STEP 1:-SELECT A SURVEY STATION
Once you have had a good look at the site, you will select a position for your survey station
from which you have a line of site to as many of the main points as possible. It is particularly
important to be able to see all the corners and places where a feature has a change in
direction. Set up the tripod legs over your selected survey station. Prepare the drawing board;
a piece of polyester drafting film is taped onto the drawing board with masking tape. The
corners are taped first, with the film pulled tight, and then the edges are taped. The board is
fixed onto the tripod.
STEP 2:- ORIENT THE DRAWING BOARD
When drawing a building you would orientate the long side of the board so that it is parallel
to the long axis of the building. If possible, for a site plan, you would orient the board so that
north is up the page. For all plans it is important to check that the whole site is going to fit on
the board at your chosen scale. A pin is positioned into the board to give a fixed point from
which observations and measurements can be taken. The pin marks the position of your
survey station on the board. Once the survey has commenced the plane table should not be
STEP 3:- CARRY OUT THE SURVEY
The alidade is placed against the pin and used to observe in turn, selected points. Rays are
drawn on the film and measurements between the pin and the points taken with the 30mtape.
The measurement is written onto the drawn ray as a record. Subsequently, each point is
plotted along the ray at the selected scale, ' with a scale rule. Observations and measurements
are taken to as many points as required to allow the shape to be recorded. These plotted
points create an accurate framework around which the rest of the plan can be constructed.
This method is most useful for plans of single buildings or small siteswithin a radius of 30m
from the plane table.
EQUIPMENT REQUIRED FOR A PLANE TABLE ANDALIDADE
SURVEY:Plane table, tripod legs, alidade, spirit level, 30m tape, polyester drafting film, hi-polymer
6H pencil, masking tape, pin, scale ruler, compass, ranging rod for sighting, plumb bob.
EXAMPLE OF PLANE TABLE SET UP:-
EXAMPLE OF DRAWING PAPER AFTER ALIDADE
MERITS AND DEMERITS
It is most suitable for preparing small scale map or surveying small area.
It is most rapid method.
Field book is not necessary.
No great skill is required for satisfactory map.
It is particularly suitable for magnetic area where prismatic compass is not reliable.
Contour and irregular object may be represented accurately.
It is less costly.
Plane Table Essentially a tropical instruments.
It is not suitable to work in wet climate.
There are several accessories to be carried out and therefore they are likely to be lost.
It is not suitable for accurate work.
As all we know that the use of total station have made the plane table and alidade
intomuseum pieces because of the technology changes during 19th century .The aim of using
the plane table is to show how the traditional way to use the alidade without the help of
thetheodolite and the total station while drawing and plotting the points on the drawing paper
.We should be thankful because of the scientist that has made a lot of
experimentduring inverting the alidade and the theodolite to use with the plate table. Now,
modernsurveyor can use the total station as their main instrument but they will never
forget what is plane table is about.
The following sites, blogs and research papers have been referred in order to complete this