Questions tagged [ecef]
Use this tag when referring to ECEF - earth centered, earth fixed when using a geographic coodinate system.
32
questions
0
votes
0
answers
56
views
Geodetic to ENU conversion
I am trying out geodetic to enu conversion. I tried this pymap3d's geodetic2enu function:
import pymap3d as pm
lat0 = 37.7749 # deg
lon0 = -122.4194; # deg
h0 = 10.0 # meters
lat = 37.7750 # ...
1
vote
0
answers
129
views
Converting geodetic coordinates to ENU coordinates
I am trying to understand conversion from geodetic coordinates to ENU coordinates. As per this wikipedia page, its two step process: geodetic to ECEF coordinates and then ECEF coordinates to ENU ...
1
vote
1
answer
139
views
When do permanent RTK base stations need to update their advertised ECEF coordinates to account for continental drift?
I have recently setup an L1/L2 RTK base station in the UK, with the data served via rtklib, NTRIP and rtk2go.com. With a matching rover I am getting reliable 10mm fixes with excellent repeatability ...
1
vote
0
answers
58
views
Transform TEME TLE derived positions of a GPS satellite to the WGS84 coordinate system for comparison
I am trying to compare TLE derived x,y,z positions of a GPS satellite with those derived from precise GPS ephemerides (NGA). However, I am having some trouble getting the coordinate systems and ...
2
votes
0
answers
196
views
Calculating ECEF position of gps satellite?
I am calculating the ECEF positions of satellites but the results are not what I expected.I'll show my code below but I'm following the gps specification(converting to radians from semicircles and the ...
3
votes
1
answer
167
views
Difference in variation of ECEF X and Y data from GNSS
I am logging ECEF data from multiple GNSS receivers and notice that there is always more variance in the the Y (latitude) axis than in the X axis of a scatter plot. Attached is a plot showing the ...
1
vote
0
answers
120
views
Convert a body vector relative to an aircraft, to a vector in ECEF space
I am trying to solve for a problem where an observer is on an aircraft with a given pitch, roll, and yaw. The observer is looking at an object which produces a line of sight vector that is measured ...
2
votes
0
answers
3k
views
Converting Velocity ECEF to NED or LLA/Geodetic
I'm able to get a correct position from ECEF to Geodetic to NED with a relative footpoint and can verify using online conversion tools:
https://www.oc.nps.edu/oc2902w/coord/llhxyz.htm
https://www.ngs....
1
vote
0
answers
462
views
Converting from Lat Long Altitude to Geocentric to Topocentric using modern PROJ C++
I'm trying to use Proj to perform lat long alt to geocentric to topocentric transforms.
I've been able to do this fine in python, but the API pyproj uses underneath is apparently very old. I want to ...
1
vote
1
answer
2k
views
Relationship between ECEF and WGS84
What’s their relationship or difference?
I’ve read that WGS84 uses ECEF, but they can be converted between one another. If not mistaken, they are both geographic coordinate systems and not projected ...
0
votes
0
answers
168
views
Getting displacement in meters from "XYZ ECEF" or "NMEA" data
I am new to this field. I am working on a GNSS receiver that gives me live location data in NMEA and XYZ ECEF format.
The receiver is mounted on my rover and I wish to use this data to get the rover's ...
0
votes
0
answers
610
views
Transform height position from ECEF (EPSG:4978) to RH2000
I'm a novice regarding coordinate system and projections, and I'm trying to transform ECEF coordinates (projection adopted by Cesium) to the Sweref99 projection including the RH2000 height system (for ...
0
votes
0
answers
383
views
Comparing two point clouds, one in WGS84 and the other in ECEF
I'm really a newbie and this task seems over my head. Suppose you have one cloud from LiDAR (a LAS file) with coordinates in WGS84 and another cloud, obtained from structure-from-motion, in ECEF. They ...
1
vote
1
answer
854
views
Import 3D tracking data in ECEF coordinates from a Google Earth Studio project as a layer of of points into a WGS 84 QGIS project
In addition to the rendered frames, Google Earth Studio has the option to generate a .jsx or a .json file with the 3D tracking information. (for information see https://earth.google.com/studio/docs/...
3
votes
3
answers
3k
views
What is the height reference point when using Longitude, Latitude , Height coordinates?
I'm using a library to convert LLH(WGS84) to ECEF coordinates. Does height (for corresponding longitude and latitude) denote height above/below the designated earth radius (I'm using 6378137.0m) or ...
3
votes
1
answer
967
views
ECEF coordinates to geodetic coordinates: Where is error in calculation?
I know, there are several questions to this topic, but I am just searching for the error in my own equations. I have no deeper geodetic background, but I am trying to understand these formulas instead ...
1
vote
1
answer
594
views
ECEF elevation to LLH height
I have an ECEF position as:
x: 1776694.9644800487,
y: 5759463.252896432,
z: 2079310.7706825584
Using some online ECEF to LLH converters, this value is transformed to:
19.152548, 72.855909, 8.00
I ...
3
votes
1
answer
542
views
How can you convert between geographic data from and to 3D data in PostGIS?
Is there was a way to convert a geography value to a 3D geometry value (in ECEF, for example), and vice versa? I know how to convert between geography using a 2D projection, but not a 3D reference ...
1
vote
1
answer
585
views
Can we say ECEF datum like in Geodetic datum?
Commonly we use geodetic datum to describe the geoid, a distorted ellipsoid model of the Earth, but is it correct to say Earth-Centered Earth-Fixed (ECEF) datum?
Because we are applying ECEF to a ...
2
votes
1
answer
3k
views
Treating latitude/longitude as a pair of polar coordinates
I have latitude longitude coordinates covering the whole globe that I wish to perform arithmetic operations (mean, interpolation) on without concern for ambiguous points and wrap around and without ...
2
votes
1
answer
10k
views
Local ENU point of interest to ECEF
I have a local ENU coordinate system on the surface of the Earth (similar to this question: GPS coordinates to XYZ on relative grid). I know the lat,lon,alt of the local ENU origin, and thus I can ...
0
votes
1
answer
955
views
ECEF to relative displacement in meters
I have GPS NMEA (National Marine Electronics Association) data that I collected being stationary and I can see the displacement of 4 meters just by looking at GPX data uploaded to google maps.
I am ...
0
votes
2
answers
5k
views
Units for LLA to ECEF conversion
I wish to implement this formula from Wikipedia to convert LLA to ECEF
coordinates:
where
and a and b are the semi-major and semi-minor axes respectively.
My question is: what units will this ...
1
vote
1
answer
2k
views
Using local mean sea level (LMSL) as altitude for converting latitude longitude altitude to ECEF
I am new in Geographic area and would like to convert latitude and longitude coordinates into ECEF x,y coordinates so that I could do some linear calculation of line or circle equation. I was able to ...
0
votes
1
answer
219
views
Using Tissot's Indicatrix Validate Conversion to ECEF
When using NED & ECEF as CRS:
https://www.mathworks.com/help/map/ref/ned2ecef.html?requestedDomain=true
Am I should worry from getting 'classical' projection issues?
For example when x,y are ...
1
vote
1
answer
706
views
Parametric equation with latitude and longitude
I have an arc described by three points: arc center, starting point, ending point.
In order to calculate intermediate points of the arc, I would normally use the parametrized equation.
x(t) = x(...
5
votes
0
answers
1k
views
Using PROJ.4 to convert from 3D Cartesian ECEF coordinates to Lat/Long coordinates with inverse Icosahedral Snyder Equal Area (ISEA) projection
I have a set of X, Y, Z coordinates in the Earth Centered Earth Fixed (ECEF) geocentric system. I need to convert them from ECEF coordinates into Latitude/Longitude coordinates using an inverse ...
0
votes
0
answers
522
views
Importing ECEF WGS84 into ArcGIS Desktop?
I have a file in ECEF WGS84 in meters.
I want to import these points in ArcMap 10.5 as point layer.
The file to import is in Excel format.
I can import them with Excel to layer tool. I can see all ...
1
vote
1
answer
796
views
How can I project earth centered cartesian coordinates (EPSG:4978) to lat lon within Geoserver?
I have a PostGIS database with X, Y, and Z ECEF coordinates and I want to create a layer in Geoserver that displays these coordinates as points in OpenLayers. In Geoserver's create layer page there is ...
1
vote
0
answers
1k
views
Perform Calculations in Cartesian Frame (NED/ECEF) Vs. Geodetic Frame
I'm recording robot's path (using INS) in Cartesian frame coordinates (x,y,z) relative to origin point. So essentially I've created NED coordinate system.
Origin point has exact (in advance measured) ...
2
votes
2
answers
8k
views
How much error should occur when converting WGS84 to ECEF coordinates?
The method is not recommended for distances larger than 4km. I am getting reasonable accuracy in terms of the east and north bearings, but for the up direction I am getting error upwards of 1km for ...
4
votes
1
answer
2k
views
Averaging Cartesian ECEF coordinates then converting to WGS84 without latitude drift
Preface: I'm unsure if GIS or math is the correct community for this question.
I have a set of 9 WGS84 latitude/longitude (degree) pairs for which I need to find the weighted average of.
To prevent ...