How to calculate local position into absolute position

[Lurker]

I have a cloud radar data in ascii mode

its consist of point with local position relative to radar position, radar position itself is absolute,

so based on the position of the radar, how to calculate absolute position each point?

each point have exact same distance with another point,

you can imagine this as a Total station surveying data

 

any tool or script anything to make my job easier ?

[osurv]

Your absolutely correct, you need to imagine this as Total Station data.

Therefore, just like a total station, you need at least one reference point/object in order to orientate your survey data.

Are you able to identify a point in your radar data that you could establish an absolute position for? This would then be your 'back-sight' reference point. More than one point would be better to give you further checks and redundancy.

Assuming you have at least one point:

1. Calculate the distance & bearing between this absolute point and your absolute radar position (tip: as a further data check, the absolute difference should be the same as the relative distance).

2. Then rotate the whole data-set based on the difference between the absolute bearing and the relative bearing.

3. Then transform the xyz based on the difference between the relative and absolute coordinate of the radar position.

4. If you have more than one reference point position, you can then compare your transformed positions with the reference positions to make sure everything is correct.

Hope this helps.

osurv