GARMIN Global Positioning System Exercise
In THREE Parts: ONE, TWO, THREE...

 Garmin GPS 12 manual available online. Garmin eTrex (yellow) manual available online. Garmin eTrex Venture (green) manual available online.

Part ONE - ON CAMPUS - Gathering point data:

• All locations at UCLA are measured relative to a central datum which is arbitrarily defined as 000.00 feet North and 000.00 feet East.
• That central datum is somewhere in the middle of the flowerbed outside of Murphy Hall. It is known as control point #700.
• Determine the Latitude and Longitude of each of the following four control points (#s 527, 530, 700, and 704). In other words, fill in the light yellow boxes.
• This is what control point #530 looks like (looking West):

• Here is a map of all the control points we're interested in (527, 530, 700, 704):

• Here are some notes to help you recognize the control points: (Fill in the yellow cells...)
 Control Point Description North, degrees and decimal minutes West, degrees and decimal minutes 527 Brass monument disk #527 centered on West edge of the landing above Janss Steps. 530 Brass monument disk #530 centered on the East edge of the walk East of Royce Hall and Powell Library. 700 Somewhere in the center of the flower bed. No one has been able to find the marker. Don't trash the flowers. 704 Brass monument disk #(no number) centered on the red concrete curb. It is on the street centerline.
• Calculate the GPS distance between each point and compare your results with those of Pafford Associates Surveyors: (Fill in the yellow cells...)
 Point North, degrees and decimal minutes West, degrees and decimal minutes GPS East/West distance Error in percent: ```(GPS distance - Pafford distance) x 100 Pafford distance``` Pafford Associates Easting (feet) We will use this data. Pafford Associates Northing (feet) We won't use these data. 527 -1248.75 00.01 GPS distance >>> >>> <<< <<< Pafford distance 530 -876.68 00.01 GPS distance >>> >>> <<< <<< Pafford distance 700 0.00 00.00 GPS distance >>> >>> <<< <<< Pafford distance 704 300.30 00.00
 To convert statute miles into feet use the Online Conversion Calculator.

Keep in mind that there are at least three distinctly different criteria used to judge the truthfulness of measurements:

1. Precision - The smallest numerical reading that our instrument gives us. With the Garmin GPS-12 this is 0.001 minutes.
2. Repeatability - The extent of agreement between readings taken at different times or under different circumstances.
3. Accuracy - The extent to which the measurement coincides with reality.

Part TWO - ON CAMPUS - Finding things:

• What large features are at these two locations?
• Hint: One is too big to put in your car. The other is big enough to put your car in.
 N 34d 04.259m W 118d 26.707m N 34d 04.206m W 118d 26.447m

Part THREE - OFF CAMPUS - Over the weekend...

• Whether you walk around campus and Westwood Village, take a long hike, a bus or an automobile trip, collect a TRACK of a journey somewhere and back.
• Try to ensure that it is a continuous loop, for example, don't turn it off until it's finished.
• We would like to collect a loop in order to see if the figure closes (a measure of the truthfullness of the data).
• We would like continuous track data to import into a Windows PC application that we will write next week.
• If the track is not continuous, we will have to edit the data to make it come out the way we want it.
• "Don't try this on the freeways," but as an example here's the track of a mile-wide valentine:

click on image for a full-size screen capture