Barometer and heat

[Schagwerks]

Hi there everyone! I just got a Mavic air about a week ago. This thing is great. I’ve been flying quite a bit, sometimes in +100 degree weather but trying to stay below the 104 limit (most of the time...). Over the last couple of days I’ve been getting a barometer error. This is usually after flying for a while and the drone gets pretty warm under the battery. Is this a side affect that should be expected with heat? Thanks in advance for the help!

 

[PhoenixBird]

I’m experiencing the same thing - barometer error - in Phoenix this time of year. Doesn’t seem to affect the MA performance.

 

[silverdragon]

I like to do an experiment here on the Eastern side of the state, Connecticut..its going be in the high 90s and maybe 3 digits. I will do a continuous flight and see if the barometer errors pop up... NOW, your probably going to ask, why am I going to do this experiment... Answer, because I can........and I always like to help out other droners....and its good to see if theres an issue with the Mavic Air.

 

[Schagwerks]

Thanks for the replies, fellas. I’m fairly confident it has to do with ambient temps. I flew nonstop on one battery this morning with no issues. Yesterday when the alarm came in, my daughter was flying on the second battery back to back in beginner mode so she was going pretty slow (less air flow) when the alarm came in. Pulled the battery and man was the drone hot on the inside. Unfortunately I didn’t check the battery temp at the time but I did this morning after flying and I was around 55c on the battery at about 88f ambient. I have a day off tomorrow and I’m hoping to run a couple batteries through in the morning when it’s cooler then again in the afternoon to see if it’s repeatable. Thanks again.

 

[WithTheBirds]

You could try an IMU cal at a higher temp in an effort to correct this issue. If ambient temp takes the total IMU temp in operation above TMAX the actual value is clipped at that point and the calculated system offset won’t be able to provide a corrected value that makes sense to the flight controller.

 

[PhoenixBird]

You could try an IMU cal at a higher temp in an effort to correct this issue. If ambient temp takes the total IMU temp in operation above TMAX the actual value is clipped at that point and the calculated system offset won’t be able to provide a corrected value that makes sense to the flight controller.

Interesting idea- so you are saying do the IMU Cal outside, or in the heat?

 

[WithTheBirds]

Do it wherever the temp is closer to that you are operating in.

 

[silverdragon]

Well its 7:54 am and its 77 deg. The Mavic Air is ready to go Not hot enough. As soon as it hits 95 . BTW the Mavic Air is black so it should get super hot in 95 + degrees.

 

[Texas Mavic]

You could try an IMU cal at a higher temp in an effort to correct this issue. If ambient temp takes the total IMU temp in operation above TMAX the actual value is clipped at that point and the calculated system offset won’t be able to provide a corrected value that makes sense to the flight controller.

Have you confirmed that this works? If so that’s a great tip!!!

 

[Schagwerks]

Have you confirmed that this works? If so that’s a great tip!!!

You could try an IMU cal at a higher temp in an effort to correct this issue. If ambient temp takes the total IMU temp in operation above TMAX the actual value is clipped at that point and the calculated system offset won’t be able to provide a corrected value that makes sense to the flight controller.

I’ll try that. I did a calibration inside earlier this week at about 76 degrees. Unfortunately I haven’t had a chance to fly it in the last couple of days! Thanks for the suggestion.

 

[Olav van Gerven]

My theorie what might be the cause: The barometer must have a sensor that reacts to the outside pressure through a referenced pressure inside. As the temperature raises to much, this reference pressure might be influenced and rais "artificial" by the heat causing the air to expand. If a certain tolerance is crossed, the system might give an error message.
IF this is the case (theorie, don't forget) the calibration in the higher temperature should work, BUT if the temp drops, a re calibration would be requiered.

 

[WithTheBirds]

My theorie what might be the cause: The barometer must have a sensor that reacts to the outside pressure through a referenced pressure inside. As the temperature raises to much, this reference pressure might be influenced and rais "artificial" by the heat causing the air to expand. If a certain tolerance is crossed, the system might give an error message.
IF this is the case (theorie, don't forget) the calibration in the higher temperature should work, BUT if the temp drops, a re calibration would be requiered.

Unlikely- simply because the elevated temperature might only cause an increase in pressure if the drone body was sealed. We know it isn’t and to the extent it was the barometer wouldn’t function as intended under any operating conditions.

 

[sar104]

Unlikely- simply because the elevated temperature might only cause an increase in pressure if the drone body was sealed. We know it isn’t and to the extent it was the barometer wouldn’t function as intended under any operating conditions.

I think he's referring to the reference pressure in the pressure sensor - not pressure inside the drone. If that's what they use then it should either be a vacuum or temperature-compensated.

 

[El NinoPerdido]

Hi there everyone! I just got a Mavic air about a week ago. This thing is great. I’ve been flying quite a bit, sometimes in +100 degree weather but trying to stay below the 104 limit (most of the time...). Over the last couple of days I’ve been getting a barometer error. This is usually after flying for a while and the drone gets pretty warm under the battery. Is this a side affect that should be expected with heat? Thanks in advance for the help!

I have been getting the same Error, everything else seems to work all controls including camera and quick links like Asteroid. I'm in Mesquite Nv. and temps are above 104. I took it to Vegas and flew for about an hour on 4 batteries and had no issue at all with outside temps of 98 deg. I'm waiting till fall and see if it goes away completely if so I will be using a frozen bag of peas under the controller next year.