During the alpha testing phase with the "APM Copter V3" code i immediately reported to the Dev Team that the Loiter mode was very accurate but is not allowed to fly normally, like with other system as DJI and Mikrokopter, Zero-UAV, etc.
We preferred to make the Loiter mode that would serve to accurately reposition the multirotor, and to help beginners to fly slowly and safely.
An italian friend and developer, Sandro Tognana, collected my challenge and started to develop a flight mode as I wanted, in line with the other famous flight control board.
Another awesome programmer, Julien Dubois, has joined our team and has worked actively to implement the complicated wind compensation.
After several months of development and testing are pleased to present the "Hybrid flight mode", in two words a "flyable Loiter" with wind compensation, the code virtually switches from "Loiter" to "Alt-Hold" and viceversa when you exit and enter a sticks deadband (configurable), considering of course the compensation of the wind, therefore complies with the tuning of your multirotor.
You can configure some parameters but already with the default works perfectly, my video speaks for itself.
This new mode is currently being debugged (in alpha phase), it is therefore not available to the public, of course, will have to go into the hands of APM Copter Dev Team who will decide whether to adopt it in an upcoming release.
The results in my video are great, sorry but the audio is bad because it was very windy today, however, is clearly seen as a "Hybrid" works, is almost perfect.
In the second video by Julien you can see the Hybrid in action vs a "DJI Phantom 2" quad with "Naza 2" inside, imho Hybrid work better than the "GPS Position Hold" of DJI, especially on braking.
The tests were carried out on APM and VR Brain, but of course will work on any board that installs "APM Copter" as PX4 and Pixhawk.
I will keep you updated on the "Hybrid" developments, i'll open a discussion about this with other APM Copter developers to assess any changes in the code.
I want to say thanks to Sandro and Julien for their great work!
Bests, Marco
Comments
Hi Wolke,
thanks for testing the mode!
You've noticed the same things we're trying to fix.
About the altitude drop, I thought that was a baro problem and I try to fix it atm but seems that other firmware releases suffer less from that issue. We are using 3.1.1 rc1 and maybe this problem will be solved once merged into master (onion)
About the loiter to manual transition, many pple noticed this twitch. We know where it comes from and will try to smooth it as much as possible but, once again, stick inputs are smoothed in the current master code, so I hope it will be benefit for hybrid as well!
Finally, GPS glitch will have an effect in hybrid while loitering the same way it has an effect in true loiter mode as hybrid is using loiter code for loitering. So it could be a more general fix that removes the GPS glitch. A good work has been done by Randy and others on that issue and I dunno if their patch was in our 3.1.1 rc1 basis or just arrived with laster releases.
@Wolke: the drop altitude problem when translate is normal and not affect only the Hybrid, is a problem inside APM Copter.
When release 3.2 will be inside the new EKF which promises very well, even on solving this problem.
@Arfin: is officially available only when 3.2 go out.
Hi all,
Need info when exactly this flying mode is officially available on apm firmware ?
Thanks
Arifin
hi,
last days i fond some time to test hybrid loiter. first i was very agreeably surprised. flying hybrid-loiter close the gap between loiter and stabilised flying. super :).
but after more tests i also noticed some real problems especially flying smooth for video recording. first, transition between hovering(loiter) and smooth flying into an direction feels wobbly. also the same drift problems than in normal loiter mode are there. one of my main problems in loiter was the transition between hovering from an initial video position into an camera move. in dependent from gps quality you have drift problems. mostly sidewards. a no go if you try to take a smooth video track. the same happens in hybrid loiter if you try to start moving very smooth. is it possible to configure the transition between loiter(hovering) and moving copter, to make it possible to start moving from hovering(loiter) without the loiter(gps) drift problems.
second, and more dangerous. i noticed altitude drop in transition from moving(flying) into an direction while centring sticks to stop moving. here my hexa mostly drop altitude between 2-4 meters. i noticed this behaviour on all flight modes i test with my merged hybrid-loiter firmware(alt-hold, loiter and hybrid-loiter). i use stable 3.1.2 firmware and merge your hybrid loiter branch. i am not sure if the merge is the problem, or if the problem is because the functions in hybrid loiter. i record a small video. here i fly the copter sideways in hybrid mode and then center my sticks. throttle is al time at 50%(center position). sometimes i have to pull throttle up to prevent lose control of my hexa. as you see in video the copter lost mostly massive altitude. with stable 3.1.2 firmware i do not noticed this altitude problem. my setup was the same.
the video:
how ever, i like the new mode. thx.
Ok Fabio,
Well, there are some points to clarify:
1 - Actually, Alt_Hold and Hybrid use the same throttle controller.
2 - When you engage LAND mode, that is a full mode engaged and not an option of alt_hold neither hybrid, so whatever mode enabled before, the copter's behaviour will be the same.
So, you've noticed 2 different behaviours for a same mode.
Maybe a wind gust disturbing baro or a false positive "land_detector" in first case.
Anyways, DO NOT put throttle to 0 until the copter is fully landed, whatever the flight mode.
Please make some tests keeping a middle throttle during auto_landing just to see if the problem is a thorttle_controller disturbance or a false land_detector. Windy conditions is better in case of wind disturbance.
Hello Julien,
if you look immediately after the first attempt, I tried again and then putting in Alt Hold Landing, the landing strip was carried out smoothly without any problems (as you can see from the line 9000).
I was flying in Hybrid mode activated with the CH7 the Landing, the Quadricopter started to decline to make the landing with the right speed, up to here everything is ok, when I reset the throttle (to activate the procedure disarm once landed) at this point the engines have decreased the number of turns very quickly.
Repeating the same procedure soon after but then AltHold CH7 Landing, reset the throttle landed without problems.
greetings
Fabio,
After reading the code and your log/params, you should increase your RTL_ALT param (currently 5m, that's not enought imo) that could cause a bad behaviour at LAND engage if your position is higher than these 5m. Or crash on a tree in case of failsafe RTL!
But, there, you engaged LAND at a lower altitude and the descending speed should have been 40cm/s (your land_speed param). So, except a baro disturbed (by wind for example) or accel disturbed (resonance at some RPM), I can't find any bug in the current code (I mean the code located in the hybrid repository).
The bad behaviour with high throttle variations is due to baro disturbance, so it could be a common cause to both issues.
Actually, APM baro is a real problem, it's the source of most of the bugs I try to fix.
Hello @ marco,
Sure, I'll send you the log file of the problem occurred approximately at line number 8500.
greetings
https://drive.google.com/file/d/0B9fql43ddpMebG5uTERmZEZCRkE/edit?u...
Hi Jay, wait the 3.2 release with Hybrid inside.
Hi Marco, I want to try this in pixhawk. Can you guide me on how to do it?
-
4
-
5
-
6
-
7
-
8
of 23 Next