LibrePilot Forum
Users => Vehicles - MultiRotors => Topic started by: aa8mc on February 08, 2016, 07:29:18 pm
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This is my first multirotor build so I'm sure this is probably a noob oversight. I am working on a Flamewheel F450 clone with a Revo and a generic UBLOX 7M based GPS. I am running LibrePilot 15.09 on everything. I got the quad running pretty well without the GPS save a little PID tuning. I added the GPS, which I am reasonably sure doesnt have an aux magnetometer in it. I plugged in the GPS and after a while i can get a pretty good fix with about 12 satellites just in my back yard. Now I want to switch the attitude estimation algorithm so that I can use the GPS for Position Hold and the like. When I switch over and reboot the board, I get critical alarms on ATTI, STAB and MAG. I understand that in INS13 mode that ATTI and STAB are dependent on good GPS fix and magnetometer readings. The GPS is green but MAG is red. I set the home location. I ran through the calibration procedures multiple times. When I calibrate the magnetometer, the MAG light goes green and all is well...until I move the quad at all. Then it goes red again.
EDIT: Fixed the attachment
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I have exactly the same issue :-[
But I found out the following:
If vehicle is not moving the GPS position jumps slightly. This causes a gps-course and gps-speed value. The gps-course changes every few seconds. The magnetometer reports the right value. You can see the gps-course and gps-speed on the gps window. As soon as real mag-heading and gps-heading differ more than 5 degrees the alarm cahnges to orange, if the difference is greater than 15 degrees the warning gets red.(according to the pre defined values in gps setting)
Can anyone help ???
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I'm wondering if it's just a matter of us having had the misfortune of buying cheap GPS modules. I'm very seriously considering sending this one back and getting the more expensive one with an external antenna.
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I believe I might be having the same problems as you. whenever the GPS is enabled in the attitude algorithm the mag and ATTI sensors go crazy. I have tried calibrating and re-calibrating in different areas to see if there was interference, but had the same result. I uploaded a video of what was happening to YouTube.
https://www.youtube.com/watch?v=19BrfNeEYu4 (https://www.youtube.com/watch?v=19BrfNeEYu4)
any Ideas?
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When you are using the Basic algorithm only Gyros and Accelerometers are taken in account.
Using INS13, all sensors are taken in account and your MAG is Red.
https://librepilot.atlassian.net/wiki/display/LPDOC/INS13+-+GPS+Navigation#INS13-GPSNavigation-Complementaryfilter
How did you set the HomeLocation ? I think i see a 0 altitude in Attitude page.
You need a MAG without alarms first at all.
Even if your MAG is ok you can't receive a reliable GPS data indoors: Position and Velocity stable.
You can validate the first 5 steps, move your quad around all axis and finally save the last step.
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As soon as real mag-heading and gps-heading differ more than 5 degrees the alarm cahnges to orange, if the difference is greater than 15 degrees the warning gets red.(according to the pre defined values in gps setting)
GPS heading refers to path direction when the quad move, you can move backwards and facing at opposite. So in fact using a multirotor the GPS.heading and Mag.heading differs.
When steady the heading is not really defined but can do big jumps if you are indoors.
A small example where the data from both sensors do not match: https://youtu.be/EBAEDeS3200?t=23s
Using the World Mag Model the board know how is the vector that represent the mag vector expected from the home location. If differs from 5% (Orange), 15% (Red).
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1) Twist all your high power wire pairs and triplets: Battery to PDB, PDB to ESC, ESC to motor. This will greatly reduce mag interference that only happens when large currents flow through these wires. This does nothing to help the red mag when you are just sitting there.
2) Realise that it may not be possible to get good flight time mag health in a high power multicopter (lots of amps means lots of mag field from the wires) or in a mini or smaller quad (mag sensor is closer to the bad wiring) without using an external mag (typically part of a new GPS).
3) Calibrate your mags carefully; away from ground and metal. Mag readings happen the whole time during mag calibration, not just when you press the button, so don't let the quad get close to ground or metal at any time during calibration.
Currently, the only external mag we support is on the OP V9 GPS. We will be supporting more kinds of external mags in the next release.
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Thanks for the info. I will try again tonight. Out of curiosity when is the next release scheduled?
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And also where can I get my hands on an op v9?
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Ok so I am pretty sure I figured it out (at least in my case). The last step of the mag calibration finishes with the board in a weird attitude (on one side). I guess this may be obvious to some but you need to bring it back to level before saving the calibration.
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the v9 are not available anywhere at the moment, and to me it looks like the guys who built it have no intention to sell it anymore. Only way seems to be to get hold of a used one.
As the next version of Librepilot will support I2C Mag connection, it may not be necessary to try to get a V9. I am about to try a setup of that type. The only problem I see is that there seems quite a quality difference with M8N GPS. I have one which is super quick and very reliable, while the other continues to be slow and not very precise. There is a revo clone thread here where you can find ebay links which seem to sell good quality revo with good gps (my good one is from ebay).
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Good to know. As a software developer my self I have been thinking about rolling my own from the Next branch. I saw a pretty sweet video on YouTube of the terrain view in the PFD. Any idea as to the current stability of the rev branch?
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Ok so I guess not so much on having solved the issue. My new GPS came in and I got it and the external I2C mag wired. I got the next branch built and all my firmwares upgraded and configured. I confirmed that the mag is returning a solid vector and that the arrow is pointing forward on the GPS. Ran through the full calibration routine. I'm hoping that currents shouldn't be affecting the mag since its on a stick about 15cm above the main deck. The mag is giving a green status and but I'm still getting pretty erratic readings for overall attitude. The artificial horizon typically shows about 45 or so degrees off level. I also see a moderate oscillation. When I look at the scopes the attitude shows perfect sine waves, which from reading the EKF documentation I believe means that 2 sensors with the same priority are returning conflicting values. From the docs I also see that the way to remedy this is to change the priorities on your sensors, but that this is really a bandage on a larger problem which is the fact that the sensors are colliding. Also, it should be noted that when I put the Revo in Complementary mode, everything is as I would expect.
So I now have 3 questions:
1. How do I set different priorities on the sensors for the EKF algorithm?
2. Is there an good/easy way to debug the values from the sensors?
The GPS values seem ok/reasonable. I'm assuming the gyros and accelerometers are ok since complementary mode seems fine (maybe this is a bad assumption). Based on these assumptions I'm guessing that the issue lies within either the Baro or the Mag. Also I keep seeing references to Chinese Revo boards that have a bad capacitor in them. Unfortunately all of the references I have seen point back to the old OP forums, which are now defunct. Can anyone provide some insight into this? Is it possible that this is being caused by one such board?
Casey
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I fly the aux mag code all the time. The keys to success are:
- build with all high power wire pairs/triplets (battery to PDB, PDB to ESC, ESC to motor) twisted and a good PDB that does not produce mag field.
- set mag orientation correctly !!! this is not 0,0,0 for most aux mags ! It is usually 180 on roll or pitch, I forget which
- good mag calibration (never close to ground/car/etc the whole time calibration is running, not just save points, done via telemetry)
- use aux mag only if you have an aux mag
- allow GPS to run 15 minutes in open area outside before first flight of the day (download almanac), 3 minutes there before each flight after that
GPS / aux mag on a pole helps the mag issue.
Even the cheap GPS / mag units have good mags in them.
There is no user way to tune the strength of GPS and mags. The way it was done requires you to tune the EKF. Without a math degree or willingness to research EKF nomenclature and tuning, you shouldn't go there. :) But it is in GCS->System->Settings->EKFConfiguration. Honestly, do all the stuff at the top and it will fly without touching this.
FakeR is the R that is used by "Indoor EKF". It is used to ignore the GPS.
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Here is the aux mag setup doc I wrote. It was posted for FTT. I will add it to wiki.
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Thanks for the instructions on how to use an auxiliary mag. I am currently using S-Bus on the Main port for my receiver connection and GPS on the Flexi port. In order to use an auxiliary mag it looks like I am going to have to use the Flexi-IO port for my RX connection and revert to PWM/PPM. Is there a way I could stick with S-Bus whilst still using an auxiliary mag or is this out of the question?
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@theothercliff Thanks for the massive amount of info. I was able to get good attitude readings from the mag simply by setting the pitch to 180 on the board rotation as suggested. Haven't put it in the air yet but hopefully tomorrow. We'll see, they are calling for rain but maybe I can find a window. In any case I hit full throttle for a few seconds with the props and the artificial horizon was rock solid, so I think I'm probably in business. I'll report back with flight test results tomorrow hopefully.
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Thanks for the instructions on how to use an auxiliary mag. I am currently using S-Bus on the Main port for my receiver connection and GPS on the Flexi port. In order to use an auxiliary mag it looks like I am going to have to use the Flexi-IO port for my RX connection and revert to PWM/PPM. Is there a way I could stick with S-Bus whilst still using an auxiliary mag or is this out of the question?
Cliff's work on DJI GPS has been merged with parent repository already "LP-212 DJI GPSMag support". That means "next" development branch supports DJI Naza compatible GPS. Those send mag+GPS data over single serial line. Meaning you just would use one port. That means it will be available with next release.
If you already have such a GPS around and are eager to try new feature you can try compiling "next". Of course development branch most of time compiles just fine and works just fine, but if not then something needs to be fixed. I don't mind flying development code, but some people prefer stable releases which are more tested. I haven't tested that DJI GPS code, but some devs acquired those GPS units recently.
There is some information how to compile LibrePilot for Linux
https://librepilot.atlassian.net/wiki/display/LPDOC/Linux+-+Building+and+Packaging
Also LP is currently getting OpenSceneGraph which should already be working nicely, though I remember I had to create a file in the top cloned directory.
"echo override GCS_EXTRA_CONF=osg osgearth copy_osg > config"
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Thanks Mateusz for advising that the next release will support DJI Naza compatible GPS receivers which send mag+GPS data over a single serial line. Thanks too Cliff for your work to provide this feature which will allow me to retain the use of S-Bus with an aux mag on my Revolution. I have just ordered a uBlox M8N DJI Naze compatible receiver from China. Hopefully it should be here in the next 3 weeks. If the new release is out by then, great, but if not I may look to have a go at compiling, so thanks for the info on this Mateusz.
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@theothercliff Thanks for the massive amount of info. I was able to get good attitude readings from the mag simply by setting the pitch to 180 on the board rotation as suggested. Haven't put it in the air yet but hopefully tomorrow. We'll see, they are calling for rain but maybe I can find a window. In any case I hit full throttle for a few seconds with the props and the artificial horizon was rock solid, so I think I'm probably in business. I'll report back with flight test results tomorrow hopefully.
Glad to hear it!
Sorry to say that on Revo, S.Bus requires MainPort, and aux mag requires FlexiPort, leaving no place to connect GPS. Sparky 2 controller can do this, (because S.Bus goes on RcvrPort and/or aux mag can go on I2CPort) but not Revo. I will open a change request to see if GPS can be put on FlexiIO on Revo.
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Thanks TheOtherCliff for opening a change request to see if GPS can be added as an option for the Flexi-IO port on Revo. From a quick look at the Revo schematic and STM32F405RG datasheet, it would appear pins 7 and 8 of the Flexi-IO port could be configured as UART TX and RX. So, from a hardware perspective it looks feasible. It may also be worth considering S-Bus as an option on the Flexi-IO port too to keep all of the receiver options (PWM/PPM/S-Bus) on the one port. In that way, those with a GPS receiver with separate I2C mag can use the Main and Flexi ports. The below info is what I pulled together looking into this:
CONN2 (Flexi-IO Port) Pin 7 - U4 Pin 37 (PC6/USART6_TX)
CONN2 (Flexi-IO Port) Pin 8 - U4 Pin 38 (PC7/USART6_RX)
CONN1 (Flexi Port) Pin 3 - U4 Pin 29 (PB10/I2C2_SCL/USART3_TX)
CONN1 (Flexi Port) Pin 4 - U4 Pin 30 (PB11/I2C2_SDA/USART3_RX)
CONN4 (Main Port) Pin 3 - U4 Pin 42 (PA9/USART1_TX)
CONN4 (Main Port) Pin 4 - U4 Pin 43 (PA10/USART1_RX)
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Finally in the air and ran a good hover test. Very pleased. Perfect timing because the next phase (FPV) is supposed to be delivered tomorrow. Thanks again everyone!
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SBus can ONLY run on MainPort because there is a hardware inverter only on MainPort.
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Ah yes, there is indeed an XOR on the UART1 RX line of the main port, the other input pin of the XOR being tied to an IO pin to allow inversion to be turned on or off. So, S-Bus requires that the RX signal be inverted and the reason it has to be on the main port. In that case, why not provide the option of connecting GPS to UART6 on the Flexi IO port. That would allow those wanting to use S-Bus to connect their receiver to the main port, the I2C magnetometer to the Flexi port, and the GPS receiver to the Flexi IO port. Just a thought. There may be a reason why this is not possible?
Further edit: Cliff, I see this request (GPS on Flexi IO port) was added to the issues list for Revo on 21 Feb 2016, thank you. Let's hope it can be included in the next release.
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Hi Guys
I am having the exact same issue as the first post in the thread, is there a simple solution to fix this rather than adding a external mag?
I must have calibrated my internal mag at least 10 times trying to make my drone work with position hold and get INS13 working but all my sensors fail as described in the first post.
I have compared the Revo compass to my Iphone and Samsung S5 and its way off!!! no matter how many times i re-calibrate it.
I purchased my Revo from Banggood, with the M8N GPS
http://www.banggood.com/OpenPiolot-CC3D-Revolution-Flight-Controller-Oplink-M8N-GPS-Distribution-Board-p-1000084.html
Any help would be greatly appreciated
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Are you experiencing issues all the time or only under throttle?
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Are you experiencing issues all the time or only under throttle?
All the time when I turn on INS13
Basically No matter how many time i re-calibrate the Mag, i still get the same result when I turn on INS13. Screenshots included as attachments, this error stops me from arming the drone.
My location is Australia
I even took my drone out to a large open area with no magnetic or electrical interference and I still get the same result
Edit
Today I went and picked up a HCM5883L External mag and connected it to the flex port and configured it to I2C and that still does not work, even after following the txt document I still don't see any values.
This revo is incredibly close to going back to banggood
Edit 2
I managed to get it to arm in INS13
But it will not fly, drone just lifts up and rolls over into the grass. Included is a screen shot of the test flight
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So I have been reading and reading the forum looking for answers to how I can fix my drone, looks like I have to wait for 16.01 for external mag support as my on-board has problems that I cannot fix.
Would it be possible to add HCM5883L MAG into the 16.01 release?
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External is already included and working using the "next" branch.
Maybe you can setup you build environment and build by yourself ?
https://librepilot.atlassian.net/wiki/display/LPDOC/Mac+-+Building+and+Packaging
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Thanks for that, in terminal now copying,pasting,downloading and hopefully later on building :)
Is there anyway the main site could host unstable/beta releases in pre-built dmg format? that would super helpful
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As long as the devs are cool with it, I can see about setting up a continuous integration server to automatically build nightlies. Finding a hosted OSX environment may be tough though. I may have to figure out something else for Mac.
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Just had a quick look at OSX hostings, its like 59$US a month.. wow.
I would host it on my mac mini but my internet upload speeds are way to low, until I get fiber connected.
What about a special release dmg, call it 15.91 with external mag support?
nearly close to building the GCS but stuck on
Project ERROR: Xcode not set up properly. You may need to confirm the license agreement by running /usr/bin/xcodebuild.
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Yeah I found some as low as $29 but that's still ridiculous compared to my Linux hosts which run about $6.
Anyway, as for the build error, I'm assuming you installed XCode just for this. Make sure you open the actual GUI once and accept the license. Then you should be able to run the command line tools til your hears's content.
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managed to get passed the Xcode problem and onto the build part, now I am stuck with this when I try to build
entered
make -j8 opfw_resource
make -j8 gcs
error
code/librepilot/ground/gcs/src/libs/sdlgamepad/sdlgamepad.cpp:24:10: fatal error:
'SDL/SDL.h' file not found
edit
Oh... forgot to install the SDL framework
edit 2
Nope, that did work either after installing the SDL into my library/framework folder
I just want to fly my drone :( with external mag
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error
code/librepilot/ground/gcs/src/libs/sdlgamepad/sdlgamepad.cpp:24:10: fatal error:
'SDL/SDL.h' file not found
edit
Oh... forgot to install the SDL framework
edit 2
Nope, that did work either after installing the SDL into my library/framework folder
I just want to fly my drone :( with external mag
Do you add symlink ?
https://librepilot.atlassian.net/wiki/display/LPDOC/Mac+-+Building+and+Packaging#Mac-BuildingandPackaging-SDL
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Picture will explain my steps.
thanks for your help guys, really appreciate it :)
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I am not sure if this is an option, but how about installing VirtualBox and latest Ubuntu on it ?
Enjoy GCS and flying, while you struggle with Mac ? ;)
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I am not sure if this is an option, but how about installing VirtualBox and latest Ubuntu on it ?
Enjoy GCS and flying, while you struggle with Mac ? ;)
Getting very close to it, unix struggles :(
Has anyone got a today build in dmg format they could possibly upload to zippyshare or email me, i would really appreciate the help
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Picture will explain my steps.
thanks for your help guys, really appreciate it :)
Is the "SDL" symlink inside the Header dir ?
Try to complete the path using the "tab" key
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Picture will explain my steps.
thanks for your help guys, really appreciate it :)
Is the "SDL" symlink inside the Header dir ?
Try to complete the path using the "tab" key
Yes the SDL exists in my myosxusername/library/framework/SDL.framework/Headers
Looks like I needed to add it to my primary/library/framework
its starting to build now, so fingers crossed :)
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Really sorry guys to hijack this thread
Ok it built but it don't work?? GSC buttons don't work and menus don't work.
It did however connect to my Revo, so that's a start, either time to download Ubuntu or wait for the next release
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No need to paste all wiki content on console...
Read, understand what should appends and do step by step.
Lines starting with "#" are comments.
If you do the git clone yesterday, please update:git pull
Restart build and look if the error still:
make -j8 opfw_resource && make -j8 gcs
If ok (mean no errors), start app:
open ./build/librepilot-gcs_release/LibrePilot\ GCS.app --args -reset -log ~/gcs.log
This also generate a file "gcs.log" in your home directory, useful if errors.
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gave up on osx, after following your steps the GCS still didn't work correctly.
So I decided to give Ubuntu in VMware a try, everything looked so promising until it failed connect to my Revo, even though it could see it????
Also didnt want to connect to my oplink either, no matter how many times i hit the connect button
I cant make either of them work.......
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I think you may need the paid version of VMWare to map USB ports. Try running it in VirtualBox instead.
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Thanks, ill try that now as a last attempt.
Really sorry guys, I have really hijacked this thread with my pc issues.
Is there anyway the mods could move all my discussions this to another thread?
Its ok I have given up on all attempts now at building a branch, loaded Virtualbox and ubuntu and it decided to give me a 640x480 resolution that I cannot fix and it wont enable me to install additional drivers...
I have completely given up on my Revo, time to fly my phantom
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Bringing this discussion back to OPS issues, I have a uBlox neo 6m GPS hooked up to my revolution board and my mag sensor never stays calibrated. Even after twisting wire pairs and putting the GPS on a mast. I usually can't even take off. As soon as I switch the attitude algorithm to the GPS mode it stay calibrated until I move the drone.
Have we figured out a solution to this? I didn't really understand a lot of the previous discussion.
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I don't understand your issue.
You talk about calibration that do not stay. Calibration is stored just after you did the Mag calibration if you hit the save button.
Do you mean Mag alarm ?
Which Mag are you using, internal or external ?
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Here is the aux mag setup doc I wrote. It was posted for FTT. I will add it to wiki.
I tried your aux mag setup but when I got to auxmagsettings.type I only had GPSV9 and Ext! No Flexi/I2C. Revo felt ctlr with Ubox Neo 7m with 4 pin connector in Flexi port configured as per you setup. Help please
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The instructions for I2C require you to have compiled and be running the "next" branch of the software. I2C mag sensor support isn't in the 15.09 release.
You put the 4 pin connector in the flexi port and the two wire one in the main port? Or does your gps only have one connector? To have an external mag with only one connector it would have to be either a V9 (aka Platinum) GPS or a Naza GPS.
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Sorry I don't see my reply if 2 days ago. My GPS only has one connector, 4 pin. Don't think I am into compiling code so I guess my only option is to wait for the GPS features to work? Any info on when it will be released?
Thanks for the help, really means a lot to a newbe like me. Just so much to learn and an issue like this can eat up a lot of time I could be flying
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If it only has one 4 pin connector it would have to be either an OpenPilot Platinum (aka V9) gps or a DJI Naza gps (or clone) to work as an external mag. If you had either one you'd probably know.
Some of the gps units that only have one 4 pin connector but were sold as having a compass have the chip inside but they didn't supply the wires for some reason I've never understood. If you open the gps case and post a picture of the board we can tell you if the chip is there and just needs a cable soldered on. The chip is a tiny 3mm (about 1/10th inch) square chip usually labeled either L883 or A983.
As far as gps, any Neo-7 should work now. Plug it into either port and set that port to gps/57600/ubx. The revo should configure the gps when it boots up. A usb connection alone doesn't supply power to the gps, you need a battery hooked up before the usb.
There is no announced date for the next release as far as I know.