Measuring steps
Step 1: Set up a total station that has passed the appraisal and calibration at the control point, and set the parameters such as air temperature and air pressure according to the actual situation to accurately center and level. Because the elevation is not measured, the instrument height and mirror height can be arbitrary. Two prisms stand at adjacent control points in front of and behind the site. In this example, the sequence of the site is G2-D 1-D2-D3-G3. (This site is G2)
Step 2, aim the left position of the disc at the rear point, manually set the horizontal angle to zero, and record the reading of the horizontal angle on the observation record. Then the range can be measured several times to choose a stable value or recorded.
Step 3, align the left position of the disc with the front point. At this time, the horizontal angle reading will change, and record this reading. Then measure and record it as before. At this point, the first half of the test has been completed.
Step 4, aim the correct position of the disc at the back point, record the horizontal angle reading, measure the distance and record the reading.
Step 5, aim the correct position of the disc at the front point, record the horizontal angle reading, measure the distance and record the reading. This test is completed.
The operation returned by the second test is basically the same as that returned by the first test, with only one difference, that is, the initial reading of the set of disks mentioned above. When each station observes according to the required number of times, it will enter the next station and do the same operation until the horizontal angle of the whole part is measured.
circuit diagram
Data record
The recorder shall timely calculate 2C value, half-way turning angle value, one-way turning angle value, distance and other data.
Calculation method:
2C value = (positive and negative reading on the left of the disk 180)- reading on the right of the disk.
Angle value measured in upper and lower half = back point reading-front point reading.
Angle value measured for the first time = average value of two and a half measurements.
Average angle value = average value of each measurement. Horizontal angle.
The distance is calculated in the same way as the horizontal angle.