Hi, I'm Rami Tamimi. We've been using the survey total
station for a lot of different applications in the last several videos. Today I want to introduce you
to the concept of topographic surveying and how we can use a survey total station to find the
This can include existing features, the elevations of the ground, and any utilities
that might be present on the surface. Topographic surveys heavily depend
on elevations and being able to find out how high and low your points are.
The last several videos we've been talking a lot about horizontal accuracy, making sure we know our
distance and where we are in terms of space. But when it comes to topo, we're gonna be
incorporating everything we learned with the level and that is, finding the difference in height
between points; using both horizontal and vertical measurements, we can combine the two and create a
full featured map to show the exact conditions of the land that we're surveying. Topographic
surveying depends on three things. One, establishing a control network so that
we can figure out where we're located in our project. Second, we need to be able
to backsight a reference control point in order to establish a scale for our project.
And third, we will then be turning the angle several times and taking several foresights
and measuring different points and coding them different descriptions
so that we know exactly what we're sighting. Now, you could just use your survey total station in a
prism and store all the information on the total station. Or, you could use a
survey data collector. This data collector is going to be attached to our rod right here.
And now every time I go to take a measurement, all I have to do is input the information into
my data collector, make sure that the total station is able to see me and then all that
information is stored in my data collector. Either method is fine and you don't have to
have a data collector. It just makes things a lot easier. Now in terms of a control network,
we only have one setup. So we're only gonna need two points. The first control point is this point
right here. I'm calling it control one. The total station will be set up here the entire time.
And over here is the second control point that we'll be
setting up a backsight to. This will be a fixed rod with a prism on it.
Okay. This should be good just like that. I'm just gonna point this in the direction of the
total station. Now if you don't know how to set up a survey total station, I'm gonna recommend that
you watch this video. It goes over the basics of how to set it up. How to level it. And make
sure that you have good accuracy because I'm not gonna show you how to do that in this video. Once
you have watched that video, come back here and we will go over topographic surveying. Once you have
leveled out your total station, let's go ahead and figure out how tall the instrument height is.
The way we do that is by using this 25 foot tape. Simply pull and measure the height. Now, you want
to be measuring where this line of sight is. A lot of total stations will come with a dot that's
implemented on the side right here. This is where you want to measure to. Now you want to start
measuring by putting the tape all the way at the bottom of your point. And you want to measure all
the way up until you see where this point is at. And it looks like it's coming in at 5.05.
So our instrument height from the point -- to our scope -- is 5.05.
The same goes with this rod here. We also need to have the height of this rod.
Lucky for us, though, all we have to do is look here and see that on the rod it says that
this height is 5.2 feet. So we can just input this without having to measure it ourselves.
We're going to use both these HI's and input them into our data collector. But first we
need to sight the location of our backsight. To do this, all I'm going to do is use my total station,
and point it in the direction of the prism. Looks good. And measure. [Sound effects.]
Now, this video is making the assumption that you have coordinates on your control points. That's X,
Y and Z. We're now establishing our control network and feeding that information into our data
collector so that we can then survey off of it. I have already imputed the northings and eastings
of both control point one and control point two. What we're going to do now is tell the instruments
where they are in relation to each other. Now I'm going to be using the Carlson Data Collection
software. Now it doesn't matter what kind of software you use. It's all pretty much the same.
Same concept, same principles. So just follow along and figure out what kind of information I
have to input. All right. So first we're gonna start out by saying that we're occupying point
number one. Our instrument height is 5.05. Our backsight point is point number two and the height
of the backsight is at 5.20. Okay and now you can see that our error in the horizontal distance is
zero feet and the error in the vertical is 0.001, which is very insignificant. It is fine.
We can go ahead and set our angle and this is actually gonna be zeroing out our backsight.
So now our backsight is at zero and we can accept these settings. And this now loads in
our project. We can see control point one. And control point two. Now I have a robotic total
station, which means it's capable of rotating itself and finding the sensor on my prism. Both
the sensor on my prism and the sensor on this total station can communicate with each other,
allowing this total station to rotate and find me without having someone behind the instrument.
Now, you don't need to have a robotic total station to perform a topographic survey.
However, I am using this new technology so it will make my life a little bit easier
and it will make this process a lot faster. Okay, the first thing I'm gonna have it do is
rotate and find me so that we can start to collect data. [Device beeps]
[♫Music♫] And so the sensors find each other.
It now adjusts itself. [Device beeps.]
Great. And the communication is made. All right, let's start our
topo survey. [♫Music♫]
The following is the location of points that we want to collect. We're going to be
capturing data in this particular location. We're gonna be capturing all the features
that we can including concrete sidewalks, curbs, gutters, manholes and catch basins,
fire hydrants, signs, trees, and any other significant features along the way.
All right, so to begin, you're gonna want to raise this rod to a height that's going to
be above you and any obstructions that you see. So for me, I always like to raise this to about
six feet and I just kind of get it to six feet right here and then lock it. For anyone that's
taller, you may want to go higher. Now, you want to change the point number that you're on. I mean
we started at 1-2 for our control so it might be good to start at 100. This is a good practice,
to get your points of control away from your points of topo. Your description will be the
type of point that you're picking up, whether it's a concrete sidewalk or a manhole or a light pole,
you input this information here. We had control written here,
for when we were collecting control points. Right here we're going to put the height of our rod,
which is at six feet right now. Now we're going to be starting our topographic survey here
on the sidewalk. This sidewalk is made of concrete. So I'm gonna go ahead and call this
concrete and in the Carlson software system, denoting a number after your code indicates
a beginning of a line. Your software might be a little different. So consult with your software
manual to figure out what the code needs to be to begin a line. So I'll do concrete one.
Great. I'll insert a new concrete line. So this will be concrete two.
Now, after recording the sidewalk shots, I'm gonna go ahead and record our curb shot. This
is going to just be curb one. Okay. After taking the curb shot, I will move the instrument down
and this is our gutter. We want to take this right next to the curb
shot but at a different elevation since it's sloping down. So this will be gutter one.
All right. Now I'm at the center line of the road. This will show me exactly where water
might be going or just the sleeping of the road. So I will just code this center line road one.
Perfect. On the other side of the street, I have another curb and gutter. So I'm gonna
create a new gutter line. This will be gutter two. Okay. Take the top of this.
This will be my curb shot and this will be curb two. Now, you'll notice, we're gonna run into our
first major feature and that is this gigantic light pole. What we're going to do here is just
get as close as we can to the light pole and we're going to take a shot and call it
light pole. Light pole. This will be a new sidewalk so I'm gonna call it concrete three.
It looks like we have the same thing over here so I'm gonna go ahead and start this line.
I'm gonna go ahead and move over about 50 feet and start to take more shots and begin coding them
appropriately. Here is going to be another concrete four shot. This is gonna be concrete
three. Over here we have curb two. Down here we have gutter two. This is the center line of
the road so we'll call this center line two. This will be our gutter one. Up here, back at curb one.
And this will be our concrete two and this is our concrete one.
Now I want to survey this little area right here. I'm gonna show you how we can close out
lines so that we can start to use them again. I come down to this point right here and I can go
ahead and call this concrete one. Same thing over here. I can call this one concrete two. However,
once I come down here, you can see that the concrete actually ends right where this curb is.
My coating is going to be curb one space concrete two minus seven. This could also be E or End or
whatever your software is programmed to end lines. Mine just happens to be minus seven,
so this will be curb one space concrete two minus seven. Once you've done a minus seven,
you can now reuse this code again. So I'm gonna go ahead and use it right over
here to start concrete again. Concrete two. Also going to be concrete two. But this is
actually where the concrete ends so we'll go ahead and do minus seven. There are curbs here
so we want to make sure we're including two codes -- one for the curb and one for the concrete. Curb
one -- concrete two -- and there's a gutter so I'm gonna take a gutter shot. Gutter two. Okay,
perfect. You'll notice that we have a sign right here. We need to take a reading on the sign. Sign.
Now we ended concrete one right there. We're gonna take concrete two right here. Perfect.
And you can see we have a fire hydrant right there so we're gonna take a shot on the fire hydrant.
You want to make sure your rod is actually on the ground and you may want to just tilt it slightly
so it's just over the fire hydrant. Great. We'll take our concrete two right here. Concrete two.
We'll take our concrete one over here.
Our curb shot here and a gutter shot right here. Gutter. Perfect. I see that there is a
storm catch basin right here. I'm gonna call it catch basin. We'll come to the center of the road.
Center of road. Now move over to the other side of the road. Now we're at a curb and gutter
again. Off camera I had already finished curb and gutter one so I can go ahead and reuse them again.
Gutter one. Lower the thing here. Any time you lower the rod, be sure to put the new rod height
into your data collector so it can re-account for the elevation change. Very very very important.
Curb one -- looks like we have a tree right here, so we're gonna call for it. It looks
like it's about eight inches in diameter. So I'm gonna call it an eight inch deciduous
tree. The evergreens are the ones that look like Christmas trees, they're called conifer trees.
So this an eight inch deciduous tree. All right. We're almost done. We're in the final
stretch. I see that I have a manhole right here so I'm gonna go ahead and take a shot on that.
Manhole. And it looks like right over here, we have some kind of electricity box. I'm not sure so
I'm gonna hold that here and call it electric box. Really you can call these codes whatever you want.
There's usually some kind of standard at companies that allows the person working on the computer
to figure out these codes and generate symbols for them so that they all pop up automatically
in their drawing. Once you finish your topography survey, what you're gonna need to do is re-sight
your backsight. Ensure that your backsight is still reading an angle of zero. If it's reading
something else, that means your instrument was shifted and altered during your survey
and when I go ahead and look at my prism, take a reading, and we see that our angle is pretty
much at zero degrees. I mean it might be a couple of seconds but that's not a big deal.