So I read on facebook pages that it is advised to do an IMU calibration.

I just got the I1 yesterday. Did all the firmware updates, etc.
Today was the day to take it out for the first few short flights.
All batteries charged and I1 nicely sitting in the DJI case.

Take it to the car, drove literally a few minutes to the location close to my house.
Got the I1 out of the case and on the road.
Battery in, remote on, I1 on....out of travel mode. All components off.
Props on, turn the whole system on again. Bear with me...
Compas calibration done!
Next up IMU calibration.
Watched the video on youtube and followed the same steps. Went for the Advance option.
Pressed the key and red letters came on my screen saying something like this:
Inspire/battery overheated, please turn off and wait for 5 minutes and try again.

It was 45F....so not warm. I literally had the battery on for maybe 2 minutes...I think even less....
Overheating!

I restered the system, and went for simpler IMU calibration and got the message that all is OK.

Did a few flight without any issues...got 13 minutes out of the first battery and packed it up at about 25% left.

Posted this on Facebook also and someone suggested I talk to DJI online support which I did.

They weren't too concerned...

What I dont get, and I really haven't received a logical explanation...how can a battery overheat after 2 minutes being on...

Anyway....just FYI...

i think basic IMU calibration is more than enough. Advanced calibration need critical condition to make sure it can be "advanced". Actually when ur battery power on, it is already heat inside the battery. You won't even feel it outside the battery. If the APP tells u overheat, then it may be correct.

The IMU heats up when it is on. It should be calibrated cold. Its not talking about heat in the battery.

This is the common error message of all naza flight controllers and many ppl believed its a bug because it happend when the naza is cold as well. Every Naza owner experienced it in the phantom series for example. It seems this wasnt a bug or still not corrected? You can just wait until the inspire is cool and do the advanced IMU calibration again, no problem. Be sure that the first thing you do when starting the inspire is the IMU calibration, otherwise it will heat up again

Daninho Posted at 2015-1-10 16:45
This is the common error message of all naza flight controllers and many ppl believed its a bug beca ...

Do you have to do the IMU Calibration every time you fly? My Phantoms I only did it once in a while like after a firmware update or a mishap. When I did it I always used the "Basic" Mode.

rodger Posted at 2015-1-11 00:13
Do you have to do the IMU Calibration every time you fly? My Phantoms I only did it once in a whil ...

no you dont....

If your Inspire was shipped to you, there is the possibility that due to transportation handling the IMU might need calibration. It's easy to check after firmware upgrade. In mode>advanced settings>sensors, there is a "check IMU" selection. I agree that advanced cal is not needed, but if it says to calibrate after check IMU, then do so. After that cal, the only time it might be needed is if there was some sudden impact that might affect the IMU, or if you notice that the craft is not as stable as normal (constantly fighting to maintain position in P-GPS mode w/ no wind).

It's not a over heat issue per say. You just need a good temp range for calibration. The unit has a heater in it for the imu. So yes, even at 2 mins its more than likely already @ 80-90f . This would be to warm for a good advanced calibration.

Once advanced calibration is done. You shouldn't have to do it again unless you see drifting.

rbendjebar Posted at 2015-1-11 00:22
If your Inspire was shipped to you, there is the possibility that due to transportation handling the ...

My Vision 2 + did that when I was upgrading firmware. I rebooted the bird and all was fine, it flies good.

This is completely different than a naza calibration. Same theory but more advanced.

Blade_Strike Posted at 2015-1-11 00:33
This is completely different than a naza calibration. Same theory but more advanced.

Blade_Strike, If you are getting drifting and trying to do IMU calibration but the only option that it will let you click is check IMU and that says IMU Ok then what would you suggest?

I had a weird issue yesterday where I did auto-takeoff and once off the ground it began to pull to the right quite hard.  Gave it left stick and brought it back and let go of stick and off to the right again.  Landed shut motors down, did manual take off then got toilet bowl spinning before landing again.  Restarted app, inspire and RC then flew fine??

I would still do it if experience issues.

What you are explaining sounds more like TX drift? Was there any rapid temp change, taking the device from a warm car to cold Temps outside?

Blade_Strike Posted at 2015-1-11 02:40
I would still do it if experience issues.

What you are explaining sounds more like TX drift? Was th ...

Yes, I took it from inside (70~ish degrees to outside ~40~).

How do you do it if it will not let you click anything other than Check IMU and it says IMU is ok?  It won't give me the option to perform calibration.

Never experienced TX drift, what causes that?

Just let the copter and tx get used to the temperature change. Let it sit out of case for about 10mins.

I can still do an advance cal on the ios, anytime

Thank you Blade!

I'll try again for Advanced, i'm using Android app on LG GPAD

Blade_Strike Posted at 2015-1-11 03:46
Just let the copter and tx get used to the temperature change. Let it sit out of case for about 10mi ...

I'm taking mine outside for the first time and this sounds like good advice...

Mike

rodger Posted at 2015-1-11 00:13
Do you have to do the IMU Calibration every time you fly? My Phantoms I only did it once in a whil ...

depends on you, i do it every time before i fly. I watch the data in the assistant software and even after one flight it changes, after the 2nd its worse etc... I would definately calibrate the inspire 1 after you receive it because the package was bumbed around alot during shipping. Also after FW updates

Blade_Strike Posted at 2015-1-11 03:46
Just let the copter and tx get used to the temperature change. Let it sit out of case for about 10mi ...

Ok, so I started up the inspire, took it out of travel mode and immediately did IMU check and it said it needs calibration so I did advanced and it followed up with basic automatically.  I then took it outside and let it sit for 10+ minutes before turning it on.  I powered on and did a compass calibration before trying auto take off.  Once in the air it began to swirl around in a 6-8' circle pretty rapidly.  I brought it back down and shut off the motors.  I then took off manually and it hovered for a few seconds before beginning a slow circular drift while also yawing to the left.  I again landed and then did auto take off.  I took off, transformed and hovered in place.  Flew it up and away a few hundred feet and when i stopped in the air it slowly yawed left probably 30-45 degrees before settling down.  I then brought it back and while landing it yawed 90 degrees left with no input from me.  Doesn't Inspire the most confidence in it doing what I'm telling it to do, any suggestions?  I'm in Raleigh, NC USA and flying in my yard where i've flown all of my phantoms with no issues.  No cell towers nearby and no wind.  Also when I did compass calibration I took my phone out of my pocket and layed the phone and RC/Tablet combo 20' away from the Inspire.  AlsoIt flies inside perfect using P-OPTI with no yaw/drift at all, so that leads me to believe it's a compass/gps/software thing and not something mechanical with a motor or prop.

travissrt@gmail Posted at 2015-1-11 06:23
Ok, so I started up the inspire, took it out of travel mode and immediately did IMU check and it s ...

I'm near Raleigh. Let's get two Inspires in the air sometime.

I find that sometimes upon takeoff mine will do a small circle around the take off point, then it will move to the center of that circle and after that it is lock in well. I have lots of problems with the A2 GPS in the past, but the GPS on this aircraft will get a sold lock in every room inside my house! I can't believe how good the GPS is on this this thing. Eventually I hope to test the ground positioning sensor but I think I'll have to find an underground bunker to get far enough away from the GPS signals.

don't know why u guys want IMU Advanced calibration... Actually Basic calibration is more than enough....

MTShipp Posted at 2015-1-11 09:00
I'm near Raleigh. Let's get two Inspires in the air sometime.

For sure, email me and i'll send you my cell # travissrt@gmail.com

I agree, adv cal should only be done if the unit is not flying right.

Blade_Strike Posted at 2015-1-11 11:38
I agree, adv cal should only be done if the unit is not flying right.

So what are your thoughts on this blade?

From my above post:

"Ok, so I started up the inspire, took it out of travel mode and immediately did IMU check and it said it needs calibration so I did advanced and it followed up with basic automatically.  I then took it outside and let it sit for 10+ minutes before turning it on.  I powered on and did a compass calibration before trying auto take off.  Once in the air it began to swirl around in a 6-8' circle pretty rapidly.  I brought it back down and shut off the motors.  I then took off manually and it hovered for a few seconds before beginning a slow circular drift while also yawing to the left.  I again landed and then did auto take off.  I took off, transformed and hovered in place.  Flew it up and away a few hundred feet and when i stopped in the air it slowly yawed left probably 30-45 degrees before settling down.  I then brought it back and while landing it yawed 90 degrees left with no input from me.  Doesn't Inspire the most confidence in it doing what I'm telling it to do, any suggestions?  I'm in Raleigh, NC USA and flying in my yard where i've flown all of my phantoms with no issues.  No cell towers nearby and no wind.  Also when I did compass calibration I took my phone out of my pocket and layed the phone and RC/Tablet combo 20' away from the Inspire.  AlsoIt flies inside perfect using P-OPTI with no yaw/drift at all, so that leads me to believe it's a compass/gps/software thing and not something mechanical with a motor or prop."

To be honest, I don't know. The yaw sounds concerning and would contact support regarding it.

ppdrone Posted at 2015-1-11 00:15
no you dont....

Glad to hear that. A lot of bad rumors floating around for some reason?

Blade_Strike Posted at 2015-1-11 12:37
To be honest, I don't know. The yaw sounds concerning and would contact support regarding it.

So I didn't realize until last night that I was still running the old Android app.  I downloaded the new app and then contacted DJI support about the yaw and auto take off issue.  They ask me to send video of both so I went outside to video it and now it flies like a rock, super stable, no yaw problems and no auto-takeoff roaming...  Could the app affect that??

rbendjebar Posted at 2015-1-11 00:22
If your Inspire was shipped to you, there is the possibility that due to transportation handling the ...

My iOS app is ver 0.9.2. When I go to MC>Advance Settings>Sensors> There is no "CHECK IMU" option. What is listed is a bar IMU Calibration. When I click on the bar I get a popup that says "Make Sure the Aircraft  has been off for 5 minutes" Doesn't make sense to me to calibrate with the I1 turned off. Am I missing something?

The turning off is PRIOR to the IMU Calibration.  It is to make sure your IMU is not warmed up. Hope that helps.