The Use of GIS Technology for The Use of GIS Technology for Planning of GNSS MeasurementPlanning of GNSS Measurement

Dalibor

Bartoněk, Irena Opatřilová

Institute of Geodesy, Faculty of Civil Engineering,

Brno University of Technology, Czech Republic

SyllabusSyllabus

Introduction

Related

works

Scope

and

aim

of

the

project

Methods

of

solution

System

design

Contemporary

results

Conclusions

and

future

work

INTRODUCTIONINTRODUCTIONMeasurement

using

GNSS technology –

usage

in geodesy

Benefits

sufficient number of visible satellites on the horizon

good constellation of satellites throughout the

day

Restrictions

obstacles

in terrain

multipath

(in dense

urban

areas)

INTRODUCTIONINTRODUCTIONCContemporaryontemporary

statestate

ofof

issueissue

in the

past, the main aim of GNSS (GPS) planning

was the

determining of the most appropriate time interval for measurement

contemporary meaning –

navigation of vehicles

and persons in the

urban environment, navigation in the

airport and maritime transport,

geodesy

there are a lot of various applications and software for planning of GNSS measurement

RELATED WORKSRELATED WORKS

ApplicationsApplications

andand

software software forfor

planningplanning

ofof GNSS GNSS measurementmeasurement

1.

easier tools for planning a)

freely

accessible on the

internet:

installed on computer

on-line solutionb)

for registered users (paid)c)

part of the processing software for GNSS measurement2.

advanced tools for planning with GIS support

a)

not considering influence of multipath b)

functional tools for ArcGISc)

sophisticated tools with the

influence of multipath

RELATED WORKS:RELATED WORKS: 1. 1. easiereasier

toolstools

forfor

planningplanning

inputs of user:

location on the ground (position and height)

time data of observation (date and total time)

interval of evaluation

elevation cutoff

manual plotting of obstacles of horizon (necessity of reconnaissance)

outputs of evaluation:

number of visible satellites

elevation and azimuth of satellites above horizon

DOP values

Sky Plot

RELATED WORKS 1:RELATED WORKS 1: numbernumber

ofof

visiblevisible

satellitessatellites

Planning software (Trimble)

RELATED WORKS 1:RELATED WORKS 1: skysky

plotplot

GNSS Planning Online application (Trimble) Web Mission Planning on-line application (Ashtech)

RELATED WORKS 1:RELATED WORKS 1: DDOP OP valuesvalues

Standalone Mission Planning tool (Topcon)

RELATED WORKS 2: RELATED WORKS 2: 2. 2. advancedadvanced

toolstools

forfor

planningplanning

the

creating of simulation model of locality of

measurement on the base of 3D data

(frequently digital elevation model)

automated determination of obstacles of horizon (without any reconnaissance before evaluation of planning)

evaluation of accessibility of GNSS is often areal (number of visible satellites, DOP values)

some of them aim to

determine multipath risk

RELATED WORKS 2:RELATED WORKS 2: numbernumber

ofof

visiblevisible

satellitessatellites

SKYPLOT_DEM tool

RELATED WORKS 2:RELATED WORKS 2: GDOP GDOP valuesvalues

SKYPLOT_DEM tool

RELATED WORKS: RELATED WORKS: EEvaluationvaluation

ofof

contemporarycontemporary

statestate

ofof

issueissue

ofof

GNSS GNSS planningplanning

none

of the

advanced tools solve planning

systematic and complex (for end users)

there is not any tool for planning of individual surveying GNSS methods

for now, advanced tools are only on the level of scientific and research work

=> aim of the work

SCOPE AND AIM OF THE PROJECT

the aim is the

creating of advanced application

for planning of GNSS measurement on given locality with using GIS technology

the application for planning of measurement will examine the applicability of individual GNSS methods for the selected locality of measurement

AIM OF AIM OF thethe

WORKWORK

METHODS of

SOLUTION

Factor

algebra (to split

locality

into

sub-areas)

Optimization

(searching

suitable

GNSS method)

Fuzzy

logic

(GNSS measuring

-

uncertainty process)

Expert system

(previous

experience

of measuring)

Spatial

analysis

(DMT evaluation

in GIS)

Discrete

simulation/Data mining

(prediction

of

important

parametres

of

the

sub-locality)

METHODS of

SOLUTION

Optimization

–

for

each

sub-locality:

Where qj … quality of j-th

surveying method

ajk … parameter of j-th

surveying methodwjk … weight of parameter of j-th

surveying method

s … number of parameters of j-th

surveying method.

s

k

jkjkj s

waq

1

SYSTEM DESIGN:SYSTEM DESIGN: blockblock

schemescheme

SYSTEM DESIGN: SYSTEM DESIGN: geogeo--databasedatabase

SYSTEM DESIGN: SYSTEM DESIGN: thethe

usersusers

ofof

applicationapplication

surveyors –

manager planning of surveying

methods on given locality

area of civil engineering and agriculture –

for

navigation of earthmoving machinery

SYSTEM DESIGN:SYSTEM DESIGN: processprocess

controlcontrol

((managermanager))

the core of application

selection of needed data from geo-database

control of individual processes of planning (state diagram)

user interface

entry of

the required parameters before evaluating

display of

the results to the user

SYSTEM DESIGN: SYSTEM DESIGN: simulationsimulation

modelmodel

formed mathematical relationships

in GIS simulation of real environment in which measurement is considered

solving of tasks:

processing of data from almanac

determining of obstacles of horizon

derivation availability of GNSS

derivation of the availability of the signal of mobile operator

SYSTEM DESIGN: SYSTEM DESIGN: spatialspatial

analysesanalyses

maximum usage

of built-in functions in ArcGIS

software

in other cases, functional tools newly programmed with Python

realization of some tasks of a simulation model

SYSTEM DESIGN: SYSTEM DESIGN: expert expert systemsystem

formed personal geo-databases created in Microsoft Access

parameters gathered from surveying experience

assumption verification after each measurement

design of database depending on the parameters influencing the accuracy of the GNSS methods

CONTEMPORARY RESULTS:: statestate

diagram diagram ofof

controlcontrol

modulemodule

CONTEMPORARY RESULTS:: ER ER diagram diagram ofof

databasedatabase

ofof

expertexpert

systemsystem

CONTEMPORARY RESULTS:: databasedatabase

schemescheme

ofof

expertexpert

systemsystem

FUTURE WORK:FUTURE WORK: evaluationevaluation

ofof

planningplanning

evaluation in graphic and text form

graphical outputs for viewing through GIS:

layer with plotting, where is possible / impossible to measure by the selected GNSS method

layers with information on the number of visible satellites, DOP values, multipath risks, intensity of mobile signal, ionospheric

status, etc.

textual form as a protocol -

information about the

percentage evaluation

CONCLUSIONSCONCLUSIONS

The

aim is to create advanced application for planning GNSS based on GIS technology

application especially for surveyors, as well as in the field

of civil engineering and agriculture

So far this

has

been proposed:

block scheme of application with GIS support

mathematical model and objective function

state diagram of control module

database of expert system (ER diagram, database scheme)

next steps:

partial implementation of functional modules (according to block diagram) in Python (ArcGIS)

fulfillment of expert database sample data

testing and verification of application

Thank you for your attentionThank you for your attention

contacts:

Dalibor Bartoněk Irena Opatřilovábartonek.d@fce.vutbr.cz opatrilovai@fce.vutbr.cz

Institute of Geodesy

Faculty of Civil Engineering, Brno University of TechnologyCzech Republic