Hướng dẫn bình sai GPS Huace X20 - phần 3

CHAPTER II Quick Start
This chapter gives you a quick understanding on how to use this software by
demonstrating, with an example, the typical processing of Static/Kinematics Post
Differential GPS (DGPS) data analysis.
This chapter only gives the typical workflow of COMPASS. For More details, refer to
following chapters.
[w4]:
2.1 Static GPS data process
2.1.1 New File
Launch ‘Huace Post Process’ from Windows Start Menu.
New Project
13. New Project
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New File
- Click ‘File’>’New File’ to open a Project Setting window.
To create a new project properly. The project files should be stored in the same folder
of GPS observation data restored. ‘Project name’ on top-right could be either defaulted
or customized; ‘Coordinates System’ could be customized according to the need of
each project; and ‘New Path’ on bottom-left shows the currently path.
- Click ‘New File’ to create hierarchy folders, for example, ‘Res’, ‘Mov’ and ‘Rinex’,
which stores computation files and blank projects under the folder of observation data
file:
14. Project Setting window
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15. Blank Project
2.1.2 Input Data
GPS observation data files can be placed into system when a project has been
created.
- Click ‘File’> ‘Input’ and select the data format in the dialog-box window
- Click ‘Confirm’ to access
file choosing
dialog-box window. Refer to the figure
below
:
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16. Input Data
17. Data Formate
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- As shown in the figure above, select *.Trimble format or make a multi-choice by
pressing ‘Control’ or ‘Shift’
- Click ‘Open’ to load file(s).
18. Select wanted format
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2.1.3 Baseline Processing
19. Data Loaded Window
When data have been loaded, system gives all the GPS baseline vectors but the
information about each of the vectors is temporarily unavailable, meanwhile, a
comprehensive network shows the overall situation of the GPS network.
Next step is the Baseline Processing.
As following figure shows,
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Click
‘Baseline’
on the Menu Bar>‘
Proccess all
’ to calculate all baseline vectors with
default processing settings.
20. Process All Baseline
As following figure shows,
the progress is shown in a window in which the
situation of every single baseline is also available.
The time consumed on the baseline computation depends on the number of baselines,
observation session, processing settings of calculated baselines and the capability of
your computer. When all baselines are calculated, the result of every baseline would be
shown in a baseline list. The color of uncalculated baselines would become darker than
others. Refer to following figure:
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21. Result of Baseline Computation
2.1.4 Adjustment Settings
Checking the result is required when Baseline Processing has been done. However,
the correctness of all results is assumed in this chapter and the same correctness,
generally speaking, could be achieved with one go when a desirable observation is
offered in practice.
It is also required that some of baselines should be deleted according to
simultaneous-observation situation. The detailed introduction is not available in this
chapter.
Next is the preparation for the network adjustment.
- Open the Tree View on the main interface,
- Select known points in the observation stations on the left side called Tree View
- Right-click (broken line framed and reverse-video) on the right side
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- Select ‘Properties’.
See below:
22. Station Propertie
Station Properties Setting
, as following figure shows: on ‘Known Points’ Coordinates’
panel we select either xy/xyH for Two-dimensional Adjustment, BL/BLN for
Three-dimensional Adjustment or H for GPS Height Fitting only. Then we input the
coordinates of know points in the input fields in the middle of the panel followed by an
optional value of precision on right. Please make sure ‘constrained’ is selected,
otherwise the fixed coordinates would be invalid and ignored in network adjustment.
Please enter parameters of all known-points in the same way.
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23. Station Properties Setting
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‘
Adjustment
’> ‘
Setup
’, as shown the figure below shows:
24. Network Ajustment Setting
[w5]:
,
XP
,
On
the Setup
window, please make sure that the ‘Two-dimensional Adjustment’ is
selected. If the GPS height fitting is needed, please select ‘Height Fitting’.
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Local Central Meridian
25. Adjustment Options
Note:
Central Meridian that could be also found in ‘Coordinates System Control’
must be set
window (
describe later
)
properly.
2.1.5 Network Adjustment Processing
‘
Adjustment’>‘Run
’ to carry out adjustment or height fitting according to settings in the
last section. As shown in the figure, values in the table of each station in ‘
Observation
Station Window
’ are the result of free network adjustment which is represented by
‘Free’, the result of two-dimensional adjustment is represented by ‘2D’, the result of
three-dimensional adjustment by ‘3D’ and the result of height fitting by ‘Height’.
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26. Adjustment Results(Observation Station Window)
2.1.6 Output Results
Assuming that this result meets the users’ requirements, it can be printed out as a
conclusion.
Running ‘
Result
’> ‘
Detailed result
’ will put all contents of the adjustment results in a
HTML report that could be printed out directly.
27. Output Detailed Result
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Other methods of results-output are also offered, for more details, see following
chapters
See a complete static baseline processing progress here.
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