How to Calculate a Traverse with the Traverse Calculator

Once Upon a Time Charley Chaplin and Harrison Ford set out to do a traverse around the Center for Regional Animal Psychosis Diagnosis on the SIU Campus. The building was a long ways away from their known point and direction near the Engineering Building so their first task was to traverse to a point where they could see the corners of the CRAPD building.

This Diagram Represents Their Situation Center for Regional Animal Psychosis Diagnosis First Shot Starting Point

Their Nice Instructor Gave them a Gon Instrument to Start With Along with a Spreadsheet They input their initial information They input their First position Backsight Instrument used Survey date And height of the instrument

Because they did not do any side shots they skipped the side shot section They move right down The sheet to where They will input Information for a Foresight point they Will actually occupy.

They Moved to the Foresight Section They gave Their Foresight a Name and Entered Instrument and Survey date

With Their Instrument on Point A Charley takes aim at a Stadia rod being held by Harrison Ford at point B and then Charley reads off and enters the angles Charley indicates he is using a Zenith Angle Instrument That measures in grads (or gons)

Charley Enters the Horizontal and Vertical Angles He turns his angle to the right from the backsight to his foresight point at B and reads the horizontal angle at 242.9755 gons. He notes that he can still read the rod even if he shoots horizontal (this means he can get his change in elevation from the difference of the Height of the instrument and center rod reading). Thus he enters 100 which Is his vertical angle when the scope is level.

Charley Also Enters His Rod Readings and Instrument Height

The Spreadsheet Tells Charley The Coordinates of his Foresight Point And the Azimuth of the line that leads to The foresight point.

Harrison and Charley Plan their Next Shot They will move their instrument to point B, their foresight point and from there They will sight another foresight point that will be in a position for them to begin Taking side-shots to the building corners.

About This Time Their instructor comes up and collects their T2 gon measuring instrument and leaves them with the Heiliger Watts Theodolite which measures angles in Mills. Of course with their great skills for operating any instrument and with a spreadsheet that can do the math for any angle system they are not upset and continue with their plans.

Harrison Ford Operates the Instrument He sets it up on point B. He measures his height of instrument He backsights point A and sets his horizontal angle to 0 He enters data in his spreadsheet

Charlie Stands at Point C While Harrison turns the angle and sights the Stadia Rod Harrison enters the results in his spreadsheet. It’s a Zenith Angle Machine Reading In Mills In this case the telescope was not level. Harrison shot to the rod so that the center Rod reading was the same as his height of instrument.

Harrison Also Enters his Rod Readings Note that Harrison has tilted his scope so that the center rod Reading and height of instrument are the same.

The Computer Gives the Coordinates of Point C

From Point C Harrison and Charlie Can Take Side Shots to the Center for Animal Psychosis Diagnosis Building About this time their “make life hard” instructor changes their instrument yet again – but this time he gives them a Total Station, so maybe he isn’t so bad after all.

From Point C They Plan to Take Side Shots to 6 corners of the building

Charlie Takes the Instrument this Time and Begins Entering His Key Data He enters The side Shot point He is Shooting The instrument Date And Height of Instrument Note that the points entered on the data sheet correspond to the point names on the sketch

Charlie Also Enters His Angles And his EDM Data Note that the vertical angle shows the angle the distance was shot at Also note that they did enter the height of the reflector.

The Spreadsheet Returns the Corner Coordinates

Taking Advantage of Already Zeroing on a Backsight Charlie Turns to the C2 Side Shot Directly He Enters his Angle Data He re-enters his instrument height (spreadsheet allows this for each Side shot in case you have to Reset up the instrument at the Same point) He Enters His EDM Shot Data

The Spreadsheet Gives Him the C2 Coordinates

By Now Charlie is on a Roll He shoots in the building corners at C3, C4, C5, and C6.

Now it is time to Pick a Foresight to Get Them Around the Building. They pick a point D from which They can shoot to a point and Get the other corners of the building.

Charlie Puts his Basic Instrument Data into the Spreadsheet

He Inputs His Angle Readings And the readings from his EDM Shot

The Computer Gives them the Coordinates of Point D

Harrison Ford takes over as they move the machine to Point D They take side shots to the two corners they can see just so they can cross check that the corners stay in the same place. Then Harrison shoot to a new foresight point where they can see the rest of the corners of the building. They name the new foresight point E.

Harrison Ford Sets Up and Takes his Foresight Shot to E

He Inputs his data and gets the Coordinates of Point E

Our Band Now Moves to Point E and Starts Shooting in Building Corners When they see their instructor coming with another instrument. Yes it’s a transit that he changes out with them this time.

Charlie Finishes Shooting the Corners and then Shoots to a Foresight to Return and Close the Traverse.

Charlie Inputs His Data for the Foresight

Charlie Then Puts in His Angle Info. The transit has its vertical angle 0 horizontally instead of straight up so Charlie Puts in 2 He then indicates his vertical angle was two which – well maybe it was up – ya it Was up – I think.

Charlie Adds His Stadia Rod Readings The day is ended but Charlie and Harrison Are sure they can Close their traverse Next week. The computer returns the Coordinates of point F

The Next Week Harrison and Charlie get the Digital Transit to work with. They have surveyed in all the points around the Center for Regional Animal Psychosis Diagnosis. All they have to do is survey back to the original point by the Engineering Building.

Harrison and Charlie Plan Out How They will Close Their Traverse in Two Shots

Harrison Sets Up the Instrument on Point F He backsights to E He then foresights to the point G about halfway back to the traverse starting point.

Harrison Enters His Instrument Set-Up Data

He Enters His Angle and Rod Data The Computer Returns the Coordinates of Point G

Now Charlie Takes the Instrument He Sets Up on Point G Backsights Point F And Foresights the Starting Point for the Whole Survey (thus closing the traverse back to the original point of beginning).

Charlie Enters His Data

Now Harrison and Charlie Look to See How They Did at Closing Back on Their Original Point Location of Starting Point Location when they Got back With a quick check our survey crew finds they missed closure by 2,275 feet

Harrison and Charlie Look at Each Other (Charlie) – Maybe Dr. Paul won’t notice (Both) – No (Charlie) – Maybe its not that bad of a mistake – after all the total closure error is less than ½ mile. (Harrison) – We take a few 400 foot shots – miss closure by just under ½ mile, and say its just a little error. Someone is going to say that takes talent – not the type of talent you want to have.

Continuing Conversation (Harrison – Maybe we can hide the last part of the data and then say we didn’t know we were suppose to close the traverse back to the original point) (Charlie – That sounds like a good way to be out surveying on a weekend when he sends us back to finish)

Conversation Continued (Harrison – Maybe we ought to figure out what we did wrong and go back and just redo what we messed up) (Charlie – And how do you suggest we find out where we messed up?) Stay Tuned for Another Exciting Episode of Mining Surveying!