Short remark. 5:35 When dropping a wing in a stall, don't use the ailerons, use rudder. One of the first things, your FI tells you, when you train for PPL. ;-)
@@stratos2 In a spin use the rudder to correct direction, eg, spinning to the left input right rudder.......dont use ailerons as that reduces the wing lift more on one side making spin worse.....
cool plane. About your problem with the flaps: im not really an expert, but flaps have their own small vortices like the wingtips when theyre down, so maybe adding a small wing fence right at the outboard edge of the flaps might act like a winglet to reduce interaction without changing too much about the design. Moving the elevator up and out of the downwash/possible vortex would be a safer way of course.
Nice work! A couple of those in flight problems could have been much worse... lol Good thing you were on the sticks. I think you're spot on with the flaps creating dirty air for the horizontal stab.
Gyro error like that reminds me when the ardupilot era still used 8 bit APM, many APM clones at that time came from China had symptoms of interference with the gyro exactly like that, either at the start or in the middle of the flight, I had 3 APM at that time with the same symptoms, and after I fixed it all came from an error current voltage at l2c (should be 3.3v but it turned out to be 5v) oh, how lucky when the incident happened that you were monitoring it because if in long range flight we usually only check it maybe once a minute 🙂 Btw, the good news from that incident gave me the idea to make something to prevent that one, please excuse me time for me to made content 😁
I’m enjoying the series so far. Great build. I built a few cargo style planes an on one of them I experimented with a T-tail just for the kicks. I actually really liked they way it handled. It certainly kept the tail out of the wing downwash. It is a bit mor complicated to build because of the vert reinforcement. Unless you are planning to fly very high pitch it might be an option.
I'd love to look at a log from that flight if you have it, to compare to one of my previous flights where I had a similar issue. (air and ground speeds showing much too high) I had some of the AP guys look at it and determine it was an issue with my GPS, or at least the data it was sending to the FC, and EKF3 was getting tripped up. I moved some things around in the plane to avoid problems with RF onboard and never saw it again.
@@timtheplaneman Yep, mine was actually falling back to DCM, then trying EKF again, back and forth... lol Very much the same as what this looked like. My bet is something GPS related here, if not GPS at least one sensor is bad enough that it's messing things up.
Yeah mine was switching between DCM and EKF3 about 5-6 times during this flight. I think I read somewhere that 'lane switch' would only show if there is a compass involved. The GPS values look pretty clean, but there is a large vibration in Y which I'm suspecting is causing the EKF inconsistency. Another potential issue could be the spar occluding the GPS's view of the sky on one side. Still, I'm kinda surprised it couldn't even do FBWA at all for the whole rest of the flight though! Keith you can mail me at iforce2d at gmail or PM in the Ardupilot forums for the log file.
@@iforce2d I had something similar (shuddering in flight) due to my motor wires running too close to my compass/GPS. Tridge found it by looking in my logs. I'd love to take a look at your logs to see if I can find it, but of course the ArduPilot guys are the best.
As always great stuff and really inspiring. I just can't find the time to do it. I lost a plane due to a glitched controller I think It all happend so fast. But after rebuild and during ground tests it flipped out similar to what yours did in the air. So it sits and waits to be worked on LOL. Thanks for the great entertainment
Interesting build. I made the mistake if checking my stall behaviour in FBWA. Of course the FC puts full elevator to stop the nose dropping and picks up the dropped wing with aileron. As it was first flight I should have made myself more familiar with where the manual mode was. Found it in the nick of time and recovered from spin 2mts above the ground in an 11g pull. Plane survived, wings stayed on. Mini snow goose.
That view at 17:17 was amazing. Would make for a great sunset photo/video. So far the aircraft design characteristics and handling appear to be very good. The stall characteristics are extremely good. The waffling in pitch not breaking in a clean stall really shows how well the washout in your design is working. The vertical speed (6:20) jumps to greater than 3m/s down. It might even be that turbulence off the main wing near the stall make be limiting the amount of up elevator authority at low speeds; thus limiting a forced stall. A good thing, intentional or not. Very bizarre what happened to the flight controller/software. Wondering if it is temperature related, as when electronics begin to fail they glitch when warm. (the IMU suddenly tilting over). But also odd is the airspeed and altitude values ... seemed reasonable at times, then way off at other times. Great job being professional and handling the unexpected during the flight. I had some pucker factor just watching the artificial horizon tilt over and collapse. If this had occurred during an autonomous mission, things would have gone bad quickly. This not something that can be bench tested either!
That's one heck of a view! Hopefully the next motor mount would be much beefier... Already have some doubt about the current design when you show it back then, but then again we live and learn...
Damm that was a weird cascade of glitches. Never seen anything like it. The fact the data from the barometer, airspeed sensor and gyro were all showing weird behaviour would lead me to suspect a fault in either the firmware or the FC itself. Very strange. The way the artifical horizon was just spinning around in circles did make me chuckle though lol. Hope you figure the cause
Flying with GPS issues (or anything that prevents SRTL/RTL from working) is an emergency IMO, I would have landed ASAP. Solar activity is moderate right now. Check out this excerpt from the forums: "When K-Index is too high (3 and above) there is a good probability that the drone flying and using GPS data will be affected by solar storm activity. Solar flares can interfering with satellites including GPS satellites and their signals being beamed to earth. There is a reasonable expectation that high solar activity will cause your GPS receiver to loose it’s fix and can cause fly-aways."
I only ever noticed space weather when sometimes the older modules would take a bit longer to get a fix. M8N uses three constellations is always rock solid. Wouldn't cause spinning AH anyway. He kept his cool and proceeded to aviate and navigate, better than trying to bring it down 'ASAP' in a panic
In the early days none of my aircraft ever had any GPS, and even now it's rare that I would have an autopilot on for the first few flights of a plane, and the majority of my quads have only ever been flown with gyro. So I guess flying in manual mode by FPV doesn't feel like an emergency. At least, not until the goggles start making that "low-battery" beep... :)
Pretty sure your comment is right on the money, especially as full flaps creates a lot of turbulence that the stabilisator has to fight with. That is not so easy to fix, so maybe instead increase the length of the center section of the wing, giving more flap efficiency at a lower angle setting as it gives you a lot more wing area, higher spect ratio and most likely an even better-looking aircraft. Another solution might be add some fuselage length, but that moves the CG backwards, which maybe is a problem?! Many STOL aircraft has a bend upwards of the fuselage behind the wing (like the de Havilland Caribou). Should be possible through some simple surgery, and doesn't weigh as much as elongating the tail!
Nice and interesting video! You handled that AP failure brilliantly. I would replace the FC after this, especially on such a big plane. I had a similar issue some years ago, and it crashed my plane. Replaced the FC, repaired the plane and it still flies. 9:30 I also find it difficult to flare the plane for landing in FWBA mode. Adjusting "level" calibration can help, but flaring the plane doesn't seem to be on the menu of FWBA...
I've recently experienced those EKF issues myself and damn it is scary. In your previous video you mentioned the motors were louder that you'd hoped. Maybe the motor mounts are indeed not stuff enough and that causes vibrations that interfere with the accelerometer. It's weird though that it keeps switching back from DCM to EKF when clearly EKF is not doing well. I hope the devs are able to find a solution because this really ruins your confidence in the whole system.
I'm interested to find out more about your altitude and artificial horizon discrepancies. I've experienced the same on my first flight controller build using inav on a matek f411wte board. Everything works great until it doesn't. Although im seeing my altitude drop into the negatives. I usually fly in acro so I didn't have any control loss but if I flip into horizon mode when the issue presents itself it usually dives/rolls similar to yours. My main concern is rth not working when I need it since that was the reason I added the fc.
35 minutes, and then 27 minutes with 2.2kg payload. Battery is a Multistar 4S 10Ah. Finishing at 14.0V. For comparison 'Big Red' could fly for about 22 minutes with no payload using TWO of those batteries, finishing at 14.4V
I haven't really looked into it much but it kinda seems like a gimmick that will pass by. People having been developing propellers for a hundred years or more, often with large amounts of money at stake for efficiency, durability, noise, production cost etc. If there were significant benefits to the toroidal shape I'd expect we would have seen it in use a lot more already.
I think eventually I will have to put some landing gear on, especially if I keep increasing the payload weight. Belly landing is not really the best long-term plan.
What if you split flaps and allow stream in middle unhindered to go behind plane. I remember seeing this on big planes having two sets of flaps. Maybe just reduce them in middle.
когда выпускаешь закрылки он "вспухает" - это нормальное явление. Для балпнсировки самолёта в этот момент используют тример на руле высоты (если он есть)
such rampant misgendering.... :) Quite often in the early evening they all have a big playfight/rumble, makes me wonder if they're venting the frustration of yet another day passing without getting laid.
@@iforce2d Lol! I forget if cows are one of the species we meddled with to where they need our help to do that now. I think they're a lot bigger and dumber now, than they would be if we left them alone. In which case they're having American-style problems as far as getting laid goes.
I mean that they are all bulls here and the life-long sausage fest is probably frustrating. When there are cows around they need no help whatsoever getting to business. These bulls will walk right through a seven wire fence like it wasn't there if there's something they want on the other side. Hence this whole farm and the surrounding ones make sure there is no motivation to do that, and a flimsy single wire electric is enough.
Hey, i want to know can i use stm32 32kb version for cleanflight+ nrf 24 (integrated you made earlier). I only need gps hold function, and rest nothing. L
I don't really understand the question. Are you asking if the compiled binary will fit into 32kb? If you have already built the binary, it should be easy to see the size. If you haven't, then the only way to find out is by building it.
@@iforce2d thanks a lot! Recently i made a custom cheapass quad inspired by you sir, but while configuring multivii PID controller i found my quad was not wobbling even i pushed it to max 20 . I think it can be increased further. How can I increase this limit, please assist me.
@@iforce2d thanks for your support! Recently i made a custom quad inspired by your cheapass quad! It flies well but while configuring PID values i found the proportional is less i already max it out to 20 but it needs something 30 , in the gui it only limits to 20 , how can i increase it further! Please assist me.
Additional comment: I just found this video of an AP crashing my 165cm flying wing during an Auto mode test mission. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-wDPOUWYqpYg.html I bet the HUD would have looked very similar to yours. I ditched the FC after this. EDIT, no wait, the HUD would probably have looked normal. It would only have been reality that was scrwd up...
I'm puzzled about how would you expect to notice that even on one plane, let alone all of them, or what significance you're suggesting it has. fwiw on this plane the motors, fuselage and horizontal stab are angled to be level in cruise, according to what OpenVSP calculated to be the zero pitch moment attitude. In this case it was 2.5 degrees down relative to the wing. I think I did this for 'big red' too. When the motor is a pusher on the tail I don't bother, and just mount it straight.
Find your engineering up too scratch, like Ur models and this cnc is great, old days of hand work is gone now Ur left with engineering idea's of yours will u follow or will you lead
