SCP1000 pressure variance during the day/with temperature
Hi All,
I'm using the SCP1000 sensor (ASIC revision C) on my Autopilot and have noticed that the pressure on it changes constantly during the day The change is also gradual and not noisy. I've attributed this to the change in pressure due to temperature changes as the air warms up and cools down, but I could be wrong.
Is there a way to convert this pressure to an altitude measurement that takes into account the current temperature? All the equations I have found reference the sea level temperature. I assume that as the day progresses, the sea level temperature changes. Is there a way to reflect this in the altitude calculation and therfore obtain a steadier result?
Nima.
Replies to This Discussion
-
Permalink Reply by Dave Buckley on -
Hi Nima - yes, you will find there are variations through the day due to changes in air temperature and pressure.
Back in the olden days when I flew real planes, we would receive the current barometric pressure at the airport from the Air Traffic Information Seervice ( ATIS) before we could taxi. The cross check was that for the given pressure, we should have a reading of about 25m ASL at my airport.
Knowing the height of your base/airfield, you could periodically adjust the sensor to give that known height on the ground before each flight.
Similarly, you could just add or subtract the number of feet required to give the known height for your base and adjust your flight heights accordingly.
I hope that helps.
Contests
Season Two of the Trust Time Trial (T3) Contest has now begun. The third round was a reliablilty/aerial photography round for both planes and copters, which is now closed. Stay tuned for the next round, beginning soon.A list of all T3 contests is here.
Top Content
Groups
-
UK Ardupilot Group
29 members
-
DIYDrones - CNC Project
60 members
-
South African DIY Drones…
19 members
-
ArduCopter (traditional …
114 members
-
ArduPilot (legacy) User …
94 members
© 2012 Created by Chris Anderson.
