Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

Convert Pressure Altitude to Geometric Altitude #12

Closed
mchadwick-iqt opened this issue Mar 22, 2021 · 4 comments · Fixed by #13
Closed

Convert Pressure Altitude to Geometric Altitude #12

mchadwick-iqt opened this issue Mar 22, 2021 · 4 comments · Fixed by #13
Assignees
@mchadwick-iqt

Comments

@mchadwick-iqt
Copy link
Contributor

ADS-B altitude is reported as pressure altitude, not geometric altitude. A conversion will have to be done, and may require a barometer at the base station.

Note: this is critical for aiming accuracy for near tracking. Large slant ranges will minimize the practical impact of this effect.
@mchadwick-iqt mchadwick-iqt self-assigned this Mar 22, 2021
@mchadwick-iqt mchadwick-iqt mentioned this issue Mar 22, 2021
Merged
@mchadwick-iqt mchadwick-iqt linked a pull request Mar 22, 2021 that will close this issue
Geometric altitude #13
Merged
@luke-iqt
Copy link
Contributor

Current thinking - It looks like the Geo Alt messages are coming in from PiAware... but the adsb-mqtt bridge container may not be processing them. Going to dig some more.

It happens here:
https://github.com/IQTLabs/SkyScan/blob/main/adsb-mqtt/sbs1.py#L79

The messages from PiAware/dump1090 are in a format called sbs-1.

I got my parser from here:
https://github.com/IQTLabs/SkyScan/blob/main/adsb-mqtt/sbs1.py#L79

@luke-iqt
Copy link
Contributor

Confirmed - having the H in there caused some a ParseInt call to fail.
https://github.com/IQTLabs/SkyScan/blob/main/adsb-mqtt/sbs1.py#L127

I will see if I can add something more graceful so it will remove any letters from the value first

@luke-iqt
Copy link
Contributor

OK - I added in a little re.findall to extract the first set of numbers. seems to work now and is pulling in the Geo Alt

@luke-iqt
Copy link
Contributor

JACKPOT! It is doing an amazing job of directly centering the middle on a plane.

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Assignees

@mchadwick-iqt mchadwick-iqt

Labels
None yet
Projects
None yet
Milestone
No milestone
Development

Successfully merging a pull request may close this issue.

Geometric altitude IQTLabs/SkyScan
2 participants
@luke-iqt @mchadwick-iqt