Aditional parameters - Orientation - Java·Applied·Geodesy·3D

Greetings MIcha,

I just have a question about the orientation aproximation. If not checked my adjustment is horrible (about 5 varians factor), if checked the same is less than 1. Now, in the resulting values displayed is says for 3 of them (after aproximating them) that their values are 359.xxxx values while the forth set is about 0.000xx. It cannot possibly be that from my configuration, so my question is does this parameter need to be enabled when evaluation direction sets? Say it is just a local network used for deformation analysis, on the other hand if doing hybrid adjustment on a large scale network with leveling data? I assumed that it is the value of the angle from the azimuth to the first orientation target, but it seems more to me like it is literaly aproximating the azimuth direction.

Best regards and thank you in advance.

Hello DrB

I just have a question about the orientation aproximation. If not checked my adjustment is horrible (about 5 varians factor), if checked the same is less than 1.

When you take measurements with a classic total station, you cannot observe direction angles (i.e., azimuths), only directions. Consequently, the orientation parameter of each set is an arbitrary but unknown parameter that must be estimated. The estimated values describe the difference between the zero point of the encoder at each station and the x-axis of your (local or global) frame. If you was able to observe true azimuths, i.e. using a gyroscope, the orientation parameter is known and - in this case - not part of the unknown parameters.

Kind regards
Micha

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applied-geodesy.org - OpenSource Least-Squares Adjustment Software for Geodetic Sciences

Tags:
azimuth, Direction, Orientation

So is it more correct to leave the parameter on when having direction sets? If it always has to aproximate an orientation angle, why does it influence it in the adjustment results so much?

Hello DrB,

So is it more correct to leave the parameter on when having direction sets?

As already mentioned, it depends on your data. In set of directions (not direction angles), the orientation can be arbitrary and must be estimated with the adjustment procedure.

If it always has to aproximate an orientation angle, why does it influence it in the adjustment results so much?

I'm not sure what you're referring to. The orientation is just an auxiliary parameter.

Best regards
Micha

--
applied-geodesy.org - OpenSource Least-Squares Adjustment Software for Geodetic Sciences

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