Iron Man Helmet Heads Up Display -- Episode 415

davedarko

I love your combiners. on the altitude, you have over though it. Basically, with aircraft, you have to know the barometric pressure for any given airfield and they are all published, So you said that you were in Berlin then you can check with your local airport for the QNH values.  Berlin/Schoenefied International  Has a value of 1011 hPa (hectopascal). Now  1 millibar (mb) == 1 hPa. So as you go up in altitude hPa values decrease. So You could preprogram the reference value or the local airport, and you math would be simple:

A_{reading =    1000 hPa}

A_{ref        = -  1011}

----------------------

A_{current   =    989 hPa}

Or you could take one sample when you start A_ref then by sampling and running the subtraction against the sample you will always be at the altitude. please remember that it will not be in altitude. ie feet above the ground you will have to convert this as well and temperature can influence this as well.

to sum up  take alook at this https://sciencing.com/convert-hpa-altitude-8404260.html

davedarko

I love your combiners. on the altitude, you have over though it. Basically, with aircraft, you have to know the barometric pressure for any given airfield and they are all published, So you said that you were in Berlin then you can check with your local airport for the QNH values.  Berlin/Schoenefied International  Has a value of 1011 hPa (hectopascal). Now  1 millibar (mb) == 1 hPa. So as you go up in altitude hPa values decrease. So You could preprogram the reference value or the local airport, and you math would be simple:

A_{reading =    1000 hPa}

A_{ref        = -  1011}

----------------------

A_{current   =    989 hPa}

Or you could take one sample when you start A_ref then by sampling and running the subtraction against the sample you will always be at the altitude. please remember that it will not be in altitude. ie feet above the ground you will have to convert this as well and temperature can influence this as well.

to sum up  take alook at this https://sciencing.com/convert-hpa-altitude-8404260.html

I'm pretty sure that's what the library did already. I was looking at pressure values on a weather map for Berlin and used them. Sadly it wasn't as accurate, as Berlin is big and I was 6-7km away from the measured points and therefore had an offset of 50-60m in altitude all the time. I could have set a reference point on my balcony first though and then go higher in the building to get the difference of that instead. Schoenefeld is 20km away from my home Oh right, you said what I said in the second part. That would have been great! Thanks for the input!

davedarko great minds think alike. Way too much coffee and beer. personly I don't know which I like better.