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Erratic low level flight

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In the past few days my inspire has just been going nuts at lower levels. Soon after take off it is very spazzy lurching around stopping and starting. it seems to behave a bit better after I put the gear up but still isn't right. I had a shot yesterday where I had to hover about 30 ft above a bunch of parked cars and the drone just would not sit still in GPS mode. Even if I put it in Atti mode. At one point I was in tripod mode and that was working okay, when I took it out of tripod mode it immediately began spiraling around in about a 3 to 4-ft spiral. Not good When I bring it in for a landing it lurches around sometimes lurching two or three feet off to one side unexpectedly up and down and it typically ends up dropping itself the last 6-in. Today I will calibrate the IMU and see if that helps.
one other thing in the mix, you may have seen from one of my other posts that I have mounted the DJI air unit for FBV on this bird, but I was careful not to block any of the visual sensors underneath. I was theorizing that maybe the antennas were in the field of view of those sensors and were causing some problems, but even when I turn those sensors off I'm still having the same issues so I removed the air unit yesterday afternoon and did another flight and I think I may have had smoother results but it's hard to say. More testing today. Full IMU calibration as well as visual calibration and we'll see how we go from there.
I'm currently working on a TV show, so there's always a big crowd of production people standing around and it's either dangerous or simply embarrassing to have sketchy landings or to not be able to hold a steady shot when they want a nice up close beauty shot of a car that slowly pulls away and the drone is lurching around like a spaz.
Any other thoughts?
 
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In the past few days my inspire has just been going nuts at lower levels. Soon after take off it is very spazzy lurching around stopping and starting. it seems to behave a bit better after I put the gear up but still isn't right. I had a shot yesterday where I had to hover about 30 ft above a bunch of parked cars and the drone just would not sit still in GPS mode. Even if I put it in Atti mode. At one point I was in tripod mode and that was working okay, when I took it out of tripod mode it immediately began spiraling around in about a 3 to 4-ft spiral. Not good When I bring it in for a landing it lurches around sometimes lurching two or three feet off to one side unexpectedly up and down and it typically ends up dropping itself the last 6-in. Today I will calibrate the IMU and see if that helps.
one other thing in the mix, you may have seen from one of my other posts that I have mounted the DJI air unit for FBV on this bird, but I was careful not to block any of the visual sensors underneath. I was theorizing that maybe the antennas were in the field of view of those sensors and were causing some problems, but even when I turn those sensors off I'm still having the same issues so I removed the air unit yesterday afternoon and did another flight and I think I may have had smoother results but it's hard to say. More testing today. Full IMU calibration as well as visual calibration and we'll see how we go from there.
I'm currently working on a TV show, so there's always a big crowd of production people standing around and it's either dangerous or simply embarrassing to have sketchy landings or to not be able to hold a steady shot when they want a nice up close beauty shot of a car that slowly pulls away and the drone is lurching around like a spaz.
Any other thoughts?
If IMU calibration does not solve the problem then calibrate the RC sticks. I fixed both my Inspire aircrafts from jumping all around by calibrating the RC sticks. Let us know what works.
 
If IMU calibration does not solve the problem then calibrate the RC sticks. I fixed both my Inspire aircrafts from jumping all around by calibrating the RC sticks. Let us know what works.
It's been 20-30 degree temps as well... was wondering if that plays into it
 
Because you have modified the machine it adds many variables. I would first check all the mechanical linkages. Make sure none of the booms are loose or can rotate. Make sure the prop tips are aligned correctly.

Then calibrate all sensors. Ideally with your modifications in place as they could influence the results.

What was your satellite count when it was behaving badly?
 
In the past few days my inspire has just been going nuts at lower levels. Soon after take off it is very spazzy lurching around stopping and starting. it seems to behave a bit better after I put the gear up but still isn't right. I had a shot yesterday where I had to hover about 30 ft above a bunch of parked cars and the drone just would not sit still in GPS mode. Even if I put it in Atti mode. At one point I was in tripod mode and that was working okay, when I took it out of tripod mode it immediately began spiraling around in about a 3 to 4-ft spiral. Not good When I bring it in for a landing it lurches around sometimes lurching two or three feet off to one side unexpectedly up and down and it typically ends up dropping itself the last 6-in. Today I will calibrate the IMU and see if that helps.
one other thing in the mix, you may have seen from one of my other posts that I have mounted the DJI air unit for FBV on this bird, but I was careful not to block any of the visual sensors underneath. I was theorizing that maybe the antennas were in the field of view of those sensors and were causing some problems, but even when I turn those sensors off I'm still having the same issues so I removed the air unit yesterday afternoon and did another flight and I think I may have had smoother results but it's hard to say. More testing today. Full IMU calibration as well as visual calibration and we'll see how we go from there.
I'm currently working on a TV show, so there's always a big crowd of production people standing around and it's either dangerous or simply embarrassing to have sketchy landings or to not be able to hold a steady shot when they want a nice up close beauty shot of a car that slowly pulls away and the drone is lurching around like a spaz.
Any other thoughts?
I have had the same issue. and it is a common one. Toilet bowl is what they call it. Cause is unknown to me. Sorry I don't have a fix for you but you are not alone.
 
Because you have modified the machine it adds many variables. I would first check all the mechanical linkages. Make sure none of the booms are loose or can rotate. Make sure the prop tips are aligned correctly.

Then calibrate all sensors. Ideally with your modifications in place as they could influence the results.

What was your satellite count when it was behaving badly?
I didn't notice the satellite count, but I was outside in the wide open every time. I'll make note of it next time. Unfortunately it's snowing now and I can't go out and test things out. I will triple check all my linkages and everything.
Also, because I have added the DJI air unit and FPV to my Inspire I thought that maybe somehow that would possibly be causing interference or being visible to the sensors and freaking them out or something like that. So I removed that whole setup just in case. that was towards the end of day so I haven't gotten to really thoroughly test it out. But I had turned off all sensors and was still having exactly the same problem even with no sensors on, no landing lookout etc
 
I didn't notice the satellite count, but I was outside in the wide open every time. I'll make note of it next time. Unfortunately it's snowing now and I can't go out and test things out. I will triple check all my linkages and everything.
Also, because I have added the DJI air unit and FPV to my Inspire I thought that maybe somehow that would possibly be causing interference or being visible to the sensors and freaking them out or something like that. So I removed that whole setup just in case. that was towards the end of day so I haven't gotten to really thoroughly test it out. But I had turned off all sensors and was still having exactly the same problem even with no sensors on, no landing lookout etc
Calibrate the RC Sticks.
 
In the past few days my inspire has just been going nuts at lower levels. Soon after take off it is very spazzy lurching around stopping and starting. it seems to behave a bit better after I put the gear up but still isn't right. I had a shot yesterday where I had to hover about 30 ft above a bunch of parked cars and the drone just would not sit still in GPS mode. Even if I put it in Atti mode. At one point I was in tripod mode and that was working okay, when I took it out of tripod mode it immediately began spiraling around in about a 3 to 4-ft spiral. Not good When I bring it in for a landing it lurches around sometimes lurching two or three feet off to one side unexpectedly up and down and it typically ends up dropping itself the last 6-in. Today I will calibrate the IMU and see if that helps.
one other thing in the mix, you may have seen from one of my other posts that I have mounted the DJI air unit for FBV on this bird, but I was careful not to block any of the visual sensors underneath. I was theorizing that maybe the antennas were in the field of view of those sensors and were causing some problems, but even when I turn those sensors off I'm still having the same issues so I removed the air unit yesterday afternoon and did another flight and I think I may have had smoother results but it's hard to say. More testing today. Full IMU calibration as well as visual calibration and we'll see how we go from there.
I'm currently working on a TV show, so there's always a big crowd of production people standing around and it's either dangerous or simply embarrassing to have sketchy landings or to not be able to hold a steady shot when they want a nice up close beauty shot of a car that slowly pulls away and the drone is lurching around like a spaz.
Any other thoughts?
Turn off the VPS. If the problem persists, it's not the VPS.

D
 
If I were you I’d start by removing the FPV module you’ve added. Why do you need that on the I2 anyway? I know the stock cam is very low res but you can control the tilt and for me that’s really important.
 
Remove all add-ons, check all mechanical parts, linkages, arms for twisting, angles of motors by lining up prop tips against each other. If all good and sound, perform cold IMU calibration, compass calibration, stick calibration of your controller and VPS calibration. Then see if the problem persists. If yes, send the drone in for service.
 
I've checked all linkages, prop alignment, every single thing I can find. Calibrated the IMU. Turned off all sensors. I've tried with them turned on and turned off. Used it on a few flights yesterday and had the same results. Extremely erratic behavior.
And this was in a completely different location than the other times. Out in the open with plenty of sky.
I pulled out my backup inspire and it flies perfectly.
I'm going to have to put it in for repair I guess for someone with more knowledge than me to figure out what's going on. What do you guys recommend for that?
 
Toilet Bowling can be dangerous. SOP at work is to switch into ATTI mode during toilet bowl and land. Keep an eye on GPS count. We are not allowed to takeoff with less then 10. We have lost a couple of birds due to toilet bowling so we are required to practice ATTI switch and recovery at long range.

Normally it has to do with either IMU or compass calibrations. Even if it says the compass is normal, when the bird starts to do it at lower heights we do a compass calibration.

I do not fly the I2 much, but it is the only bird that we do are testing with and training with ATTI mode recover at about 1200 feet. I own an I1 and it seems to wobble a bit more at lower altitudes. Compass cal works to tighten it up. Sounds like you might have a bit more then that going on.

May try an IMU cal, Calibrate the compass, then calibrate the RC and see if that helps. Its free and only takes a bit of your time.
 
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I did remove that. Didn't change anything. Hard to explain why I need that if you don't use your inspire the way I do... But when working with a camera app chasing cars on a show it's really good to be able to put on the goggles jump in the camera car and chase the car. I can just see a lot better where I'm going with an FPV system than I can on the screen. Removing the FPV system did not change anything for me
 
Toilet Bowling can be dangerous. SOP at work is to switch into ATTI mode during toilet bowl and land. Keep an eye on GPS count. We are not allowed to takeoff with less then 10. We have lost a couple of birds due to toilet bowling so we are required to practice ATTI switch and recovery at long range.

Normally it has to do with either IMU or compass calibrations. Even if it says the compass is normal, when the bird starts to do it at lower heights we do a compass calibration.

I do not fly the I2 much, but it is the only bird that we do are testing with and training with ATTI mode recover at about 1200 feet. I own an I1 and it seems to wobble a bit more at lower altitudes. Compass cal works to tighten it up. Sounds like you might have a bit more then that going on.

May try an IMU cal, Calibrate the compass, then calibrate the RC and see if that helps. Its free and only takes a bit of your time.
it has only toilet bowls once. The rest of the time it's just doing crazy erratic moves randomly at different times and then flying normally for 10 seconds and then doing another crazy erratic move. It behaves the same in Atti mode
 
At this point I’d pack it up and send it to Cerritos. My guess is an IMU fault or other flight control problem. Repair costs are extremely reasonable and the turn around times are quick.
 
In the past few days my inspire has just been going nuts at lower levels. Soon after take off it is very spazzy lurching around stopping and starting. it seems to behave a bit better after I put the gear up but still isn't right. I had a shot yesterday where I had to hover about 30 ft above a bunch of parked cars and the drone just would not sit still in GPS mode. Even if I put it in Atti mode. At one point I was in tripod mode and that was working okay, when I took it out of tripod mode it immediately began spiraling around in about a 3 to 4-ft spiral. Not good When I bring it in for a landing it lurches around sometimes lurching two or three feet off to one side unexpectedly up and down and it typically ends up dropping itself the last 6-in. Today I will calibrate the IMU and see if that helps.
one other thing in the mix, you may have seen from one of my other posts that I have mounted the DJI air unit for FBV on this bird, but I was careful not to block any of the visual sensors underneath. I was theorizing that maybe the antennas were in the field of view of those sensors and were causing some problems, but even when I turn those sensors off I'm still having the same issues so I removed the air unit yesterday afternoon and did another flight and I think I may have had smoother results but it's hard to say. More testing today. Full IMU calibration as well as visual calibration and we'll see how we go from there.
I'm currently working on a TV show, so there's always a big crowd of production people standing around and it's either dangerous or simply embarrassing to have sketchy landings or to not be able to hold a steady shot when they want a nice up close beauty shot of a car that slowly pulls away and the drone is lurching around like a spaz.
Any other thoughts?
The toilet bowl behaviour points out to compass problem. Before you send it for repair I'd try one more thing. Perhaps too radical for most but in this case you have not much to loose. Remove the front cone of the craft body shell. It only requires to undo 4 screws. There lies the compass. Use a strong neodymium magnet to demagnetise the compass. Come close to the compass from front with the magnet and let it rest there for say a minute. Then slowly and gradually remove it into a distace of 3 feet. Repeat this 3 times. Then let your Inspire rest for an hour, perform the compass calibration dance on location where you experienced the problem before and see if it flies ok or better..
 
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At this point I’d pack it up and send it to Cerritos. My guess is an IMU fault or other flight control problem. Repair costs are extremely reasonable and the turn around times are quick.
When you say send it to Cerritos, is that DJI?
The toilet bowl behaviour points out to compass problem. Before you send it for repair I'd try one more thing. Perhaps too radical for most but in this case you have not much to loose. Remove the front cone of the craft body shell. It only requires to undo 4 screws. There lies the compass. Use a strong neodymium magnet to demagnetise the compass. Come close to the compass from front with the magnet and let it rest there for say a minute. Then slowly and gradually remove it into a distace of 3 feet. Repeat this 3 times. Then let your Inspire rest for an hour, perform the compass calibration dance on location where you experienced the problem before and see if it flies ok or better..
 
At this point I’d pack it up and send it to Cerritos. My guess is an IMU fault or other flight control problem. Repair costs are extremely reasonable and the turn around times are quick.
I've sent her in... will report back with results
 
Well.... crap
1615038158573.png

Here's one thing I can say... She was flying just fine (even after my FPV mod) until I took her to Utah and flew in EXTREME COLD... at which point she started having these issues.
Hard to say.
I'm trying to get through to someone at the repair facility to ask more questions and get more answers.
They have a bad tendency to only connect you with someone in the home office in china from what I can tell... but they tell me they are forwarding my request to someone in Cerritos.
Also worth mentioning, this bird was my daily driver on Season 1 of Top Gear America... so many many hours of punishing desert heat, dust, one light crash (no damage) and a LOT of banging around on 4wd roads in jeeps etc.
BUT... when I had her opened up adding that power line out, she was surprisingly clean on the inside.
Let's see if I can get a good answer and I'll report back.
Meanwhile, check out some of these shots I got yesterday at work (with FPV and Naked Gopro)
;-)
Cheers
Russell
 

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