XAircraft My X650 v4 flies like crap :(

[Frankieplus]

This is my first aircraft that I had put together by someone and in the meantime I have been using a flight sim to learn
how to fly..

I smalled the 650v a few times and broke some arms which I replaced myself.. Changed ESC's cause 1 wasn't working, changed some motors.. All good.

Anyway now that I'm learning to fly I am noticing that the heli flies real crap Goes all over the place and it's a struggle to
keep it in one spot. Just to try to explain, it's as if I have ATT mode turned off but I don't.

The yaw always seems to want to go to one side a bit too and I have to keep correcting..

I've made sure that the AHRS is calibrated, I did this with a bubble level and it's perfect.. The Compas has also been calibrated. Compus
and flight controller are facing forward properly.

Now are the gains in the flight control the only settings I have at my disposal to configure? Is there anything else that I can configure to help it
fly smooth?

What about the yaw always tilting.. Is that just a remote control trim setting or is there some software method I can use to solve this??

I've seen You Tube videos of people getting the X650 to fly nice stable and smooth - Can anyone help please?



-Frankie

 

[XAircraft America]

Hey Frankie

I have an X650 V4 that is very stable and takes great video. Have you tried taking the compass off and testing? I have noticed that sometimes that can be the issue if you are not also using a GPS. I fly with NOR for all filming and keep ATT off because it seems like the ATT mode is much less stable from my experience. If you are proficient on a sim with a 6ch heli, you should have no trouble flying with the ATT off. Just remember to use small movements and not try to over control the quad. Another possible issue, if you are running a gimbal with servos, is the need for a UBEC to control voltage to the ESCs and servos. I noticed a marked improvement in stability (and peace of mind) after installing one. Also be sure that all of your motors are mounted perpendicular to the ground, having one off will cause issues. Also be sure that all of your props are in good condition and have no damage.

Here are my settings in XAircraft Control Center that will hopefully give you a good place to start:
Stick Gain: 35 for all
Auto-Level Gain: 30 for both
Attitude Control: 50 for all

For yaw correction, do what you can on your controller and also be sure that your controller is properly calibrated in the control center. Use the Rev test feature to be sure that everything is centered at stick center.

Good Luck!

 

[Frankieplus]

Thanks so much for the info will try everything you suggested!

 

[Frankieplus]

..also NOR is basically Auto Level and Attitude OFF right?

 

[XAircraft America]

Yes, NOR (normal) is basically an unassisted flight mode where the quad will stay pretty stable but will not try to correct itself if it begins to lean one way or another. In this mode what you do with the sticks the quad will do, whereas ATT is (attitude mode) will make the quad try to auto-level with height hold if you have the autopilot module so you will feel the quad kind of "fighting" your movements a bit. If you flip the switch it is a noticeable difference in flight characteristics. The ATT GPS mode will have the quad do everything in ATT plus it will enable position hold when you release the sticks if you have the GPS module installed and are connected to enough satellites. One last thing to check is that your props are rotating correctly, if they are not it will cause yaw issues. See the photo to make sure yours is doing the same:
View attachment 12340

 

[Frankieplus]

..Sorry to type all this in one paragraph but for some reason the forum isn't letting me make spaces in this reply.. - Yeah mine is doing same as photo, thanks. I tested mine again last night in a large-ish indoor area in NOR mode and couldn't even get it off the ground, it was just going all over the place and wanted to tip over. But maybe cause it was indoors.. Will try again today outdoors. Am I meant to take off in ATT mode? Is this ok? Or am I suppose to take off in NOR mode and then switch it to ATT once in the air? The copter just seems to fly like it's a windy day when it's not a windy day.. Also when powering on is it meant to be on a level surface? Maybe this has something to do with it.. cause in the park on the grass it's not level. Lastly a GPS question, when I flick it to GPS mode the copter starts wandering off somewhere. I do set it up properly by turning it on and waiting for the green light to flash very slowly, heaps of sattelites. Then fly, switch it to GPS and off it goes! One more question sorry for all the questions.. I have a gut feeling the compass may be playing it. Now if I unplug it and put it in ATT mode what would the drawback be of not having the compass plugged in? Will this in effect turn ATT mode into something like NOR mode?? ... -Frank

 

[XAircraft America]

Could you post a video of what it is doing? It sounds to me like your AHRS is not calibrated correctly. (I know you said you used a bubble level, but it has to be perfectly level on the AHRS (not the frame) and then click calibrate while it is level. I find that the best way to do it is to sit it on a table and then put pressure on the legs to bend until it is level. NOR mode should let you fly and not really try to correct itself at all. ATT mode will make the quad try to level itself out and that is where you will see serious drifting if your calibration was not correct. It should fly perfectly indoors unless you have fans or something going on. One thing I will say is that when taking off you have to get it in the air fairly quickly before it will really fly stable...if you try to baby it up it sometimes will tip over and be unstable because the rotors are not up to speed yet.

A level surface is not important because the AHRS calibration is what sets the quad level.

I would strongly recommend disconnecting everything and starting from scratch here. Make sure you can fly correctly with just the FC and AHRS and then start adding components until you find your issue.

Can you give me your experience level with flying 6ch helis or quads other than this one? Would you consider yourself proficent or have a sim to practice with? (Not trying to blame you because there is certainly a chance that you have some kind of defective equipment. I just want to cover all of the bases). Is is a constant drift in a certian direction or are you having it wobble all over the place?

 

[XAircraft America]

One last thought: Check this page out and see if it could possibly be your issue. http://www.xaircraft.com/en/portal.php?mod=view&aid=31

 

[XAircraft America]

Also if you do not have the compass, the ATT mode will still work because the AHRS has gyros in in that allow it to stabilize, it will not have quite as accurate heading data.

 

[XAircraft America]

Sorry to be blowing up the thread here, but be sure to read this over completely to be sure that you have everything set up correctly: http://www.xaircraft.com/downloads/manuals/XAircraft FC1212-P Manual EN v1.03.pdf

 

[Frankieplus]

I might post a video soon if I can' t get this copter the way it should be.. Thanks. Regarding the AHRS, I used a bubble level on the AHRS itself and moved the legs on the heli around and stuff until it was perfectly level. As for NOR mode. Yep I can hover around now but it's very very wobbly. No way can I get it to be straight and smooth, it's a battle keeping it in position and even then it's not really in position anyway. I messed around with the gains to see what I can come up with but still although better, the copter isn't flying properly.. Occasionally it 'jolts' You hear the motor sound go higher for an instant with a very fast levelling wobble as well. Just for a split second.. Does that sometimes. . This is with level gains at around 40-50. .. As for the manual, I read that inside out and feel I understand most of it and as for my flying experience, I'm fairly new. Have been practising on Phoenix flight sim and on a real Blade MQX.. I can fly the Blade MQX (the real one not the flight sim one) pretty good, I won't say perfect but I'm very confident, I get zip around with it no problem and I can do figure 8's in the flight sim no problem as well.. .. To give you an indication of how this 650v is right now, I find I have to battle to try to keep it in any one position. It just doesn't want to be there on its own. I feel like I should be able to take my hands off the sticks for at least 5 seconds without having the copter move around too much. If I take my hands off the controller for 5 seconds the heli would wander off too much.. Or lose altitude. It's like there's wind coming at it from all directions almost even when there is just a small breeze.. ... Will keep trying settings and maybe post a video if I can't get this thing working right.. It's good to know that you have yours working fine, that way I can't blame the design.. It means mine should be flying the same.

 

[XAircraft America]

I fly with my gains at 30 and 35. Quads (all quads, not just the x650) will not just sit perfectly still in one spot by itself. In GPS position hold there will always be some wobble as it corrects itself and gets back into position. Watch some videos of position hold to see what I mean. In NOR mode you will never be able to take your hands off the sticks for 5 secs and have it stay in the same place. I can make my X650 hover very well, but it takes a lot of practice and small stick movement corrections that anticipate what it is going to do next to do it. That being said, it should respond very fluidly to inputs and not be jerky or erratic when you make movements. Can you take a screen shot of your settings in the control center and post it for me please? Just want to see how you have it set up. I would really like to see a video of how it is flying to better diagnose your issue.

 

[Frankieplus]

View attachment 12353 .. I seem to me making some progress by changing some settings. I'll make a video soon and upload it so you can see how it's flying. I've been watching a lot of 650v you tube videos and other people can seem to get it to be rock solid.. If I never had the BladeMQX to compare it to and also another generic copter I bought which also flies solid, I would just accept that this is just the way my 650v is..And I've never used GPS hold. Copter seems to wander off, will give that another go actually.. Thanks for your help so far I appreciate it...

 

[XAircraft America]

Ok, your issue is the stick gain, auto leveling gain, and attitude control gain. Turn your pitch roll and yaw for Stick gain down to 35 and the auto-leveling gain down to 30 for pitch and roll and your attitude control gain down to 50 for pitch, roll, and yaw. Click the button to disable the GPS gain and go give it a try. With gains that high, no wonder its a all over the place!

 

[Frankieplus]

Really??? Ok I'll give it a try tomorrow. (it's night here) Why disable the GPS gain? What will that do / not do ? - Also should these settings make any difference if my gimbal is mounted to the heli or not due to weight? At the moment gimbal isn't on the heli.

 

[XAircraft America]

Hello

The GPS gain should be disabled because you do not have a GPS installed. It will not make a difference whether you have a gimbal or not installed because the gyros will automatically compensate for it. If you have a gimbal with servos do you have a UBEC installed? If not you need one.

 

[Frankieplus]

I do have a GPS. By the way looks like your gain settings worked a treat! It flies a lot better now but not sure if it's perfect because I did notice that one of my copter arms is twisted to the left a little due to the screw in the arm mount being threaded.. This is what was causing the copter to drift to one side.. I will replace the arm mount on Monday and have a proper test flight. Thanks heaps so far. P.S. Regarding UBEC where do I get those? Also, will NOT having one affect the performance of the gimbal?? Just that when I did try the gimbal once I wasn't overly happy with it, results were still 'jerky'. I'm curious as to wether not having a UBEC could have been the reason..

 

[XAircraft America]

I get my UBECs from Ebay usually. You will need a 3A 5V. To install remove the red wire from each of your esc connections to your FC by lifting the plastic and removing the red wire from the connector and taping it back. Attach the power end to your extra power plug and you will be good to go. It is required to run extra servos because the ESCs are not designed to handle them and has the potential to be dangerous and cause issues under load in flight without it. Read the instruction manual from the UBEC and Xaircraft website for more detailed instructions if you need help and if you still are having trouble I can send some pictures.

 

[XAircraft America]

Also sorry about the GPS advice, didnt realize you we're running one. If that is the case you can keep the GPS gain on. That setting only affects the GPS ATT mode though.

 

[Frankieplus]

Cool thanks.. So I need 4 x UBEC's for each ESC on my quadcopter then? I'm guessing that the UBEC will power the ESC's. And that the gimbal just plugs into the flight controller and gets power from there untouched as per normal.. ?.