I wanted to test my set-up this weekend and share, well I tested a bit and this is what I can share:
Application: Aerial security platform with a OSD onboard.(The funny part)

Aircraft: My old Gentle Lady glider as a development platform with modified wing. I reduced the tip dihedral to match each main wing, about 10 degrees dihedral total. Ailerons added to the main wings (it was actually used as flaps) but it worked well. Motor mounted to front with new ply bulkhead. Total weight 972g and flew well on ½ to ¾ throttle.

Radio: E-Sky 6 channel radio and receiver with 4 servo’s. Rudder, elavator and one ea. on ailerons y-lead connected.

Power: Tower Pro 2409 motor with 40A speed controller and E-sky 1000 mAh. Lipo. @ 11.1v

Stabilization: Plugging co-pilot (CPD-4) in down stream of Ardupilot. Stabilization then achieved on channels controlled by Ardupilot .

Ardupilot: Ardupilot2 code is really great but it looked liked a bit of a problem with the Sirf-binary mode and OSD system. So I decided to stick to Ardupilot1 code for now.

In code rudder was set-up for ailerons and throttle for elevator, I added elevator reverse function in code like this:
First tab added
#define reverse_pitch 1 // normal = 0 and reverse = 1

PID & Control tab:
//Now checking if the user have selected normal or reverse mode elevator (servo)...
if(reverse_pitch = = 1)
{
return (int)(-1*altitude_output);
}
else
{
return (int)(altitude_output);
}
return (int) (altitude_output); //Returns the result
}

Then played around with servo max and min to ensure I would get about 30 degree roll and 10-15 degree pitch up and down.

Simulation: Reading all the different posts on simulation I decided that a full hardware in the loop was not really practical for me. Mainly because R/C planes fly different in real life.

I rigged up Microsoft flight simulator to send NMEA strings over serial by adding GPSout by Pete Dowson as per this post. In configuration settings note pad I did the following:
[GPSout]
Sentences=RMC,RMA,PGRMZ,GLL,VTG,GGA,GSA,GSV (Most of not required for Ardupilot)
Port=COM10
Speed=4800

Then using Virtual Serial Ports Emulator a free download I created a connector type port 10. My port connecting Ardupilot is 2 on my laptop, so 2 and 10 was then connected. With this config. I could send NMEA to port 10 and monitor Ardupilot with serial monitor on 10 as well.

Getting it all together: Test flying my old Lady I noted how much elevator is required to give a decent climb for a given throttle position and same with roll, this I memorized mentally as I would fine tune it later.

Starting by powering Ardupilot as per normal with receiver(Ardupilot, stabilization etc. all flight ready in my Gal), connecting Ardupilot to my laptop, opening Arduino IDE then VSP emulator and finally FS9 the blue GPS lock led would lock-up and Ardupilot spitting out every thing as advertised in serial monitor.(My GPS unplugged of course)

In FS9 I use Slew function to fly my way points manually the nice thing is it can be done slowly and on one axis at a time, this made observing servo position to a way point or altitude a breeze. I use A & Q for alt. control and < & > for yaw.

So turning down Co-pilot sensitivity all the way there is no stability and interferance with simulation I flew my way points and ensure I got adequate aileron and elevator movement, not too much because stabilization must be able to handle bank and pitch excesses. If I want a 30 degree bank and Ardupilot turns to a new heading stabilization would correct anything more than that.(My servo min and max came to this after some fiddling: max16_yaw 2900, min16_yaw 800, max16_throttle 1500 & min16_throttle 900).

Note I had to do the following to be able to load a modified code after simulation and corrections: Close FS9 in Arduino IDE, stop serial monitor select a different com port say 2, stop VSP emulator and then load the code to Ardupilot and check every thing in simulation again(Because VSPE split com2 it cannot be used in till stopped and same for com10 and FS9)

My next step was to check stabilization I turned it up all the way, disconnecting Ardupilot from the laptop reconnecting GPS I went outside waited for a GPS fix and blue light, switched on Ardupilot and at fast walking aileron movement to 1st waypoint was observed with stab. I was very satisfied with pitch and bank stabilization and only allowed for a +/- 30 degree bank and 10 – 15 degree pitch anything more would be corrected for.

Flight testing: So there we go, after Co-pilot calibration as per book I launched her climbing out to a altitude I recon was about 50 or 70m AGL. and trimming her nicely Ardupilot was armed. She Immediately responded and started turning towards 1st waypoint and turned nicely over it to 2nd point , it looked like she was running on rails. While en route it started to rain very lightly mmm should I abort and land nope lets see what she does… Next moment about 300 meters away very close to waypoint she started a decent of about 20 degrees nose down I observed for a moment followed by turning Ardupilot off. She disappeared behind some terrain before I could recover. Dammm.

Missing: Immediately I went for the recovery it looked like she came down very close to a double carriage road never the less I had to cross it and search in some tall grass. 5 min later and no sign of her I noted a pick-up and two guys getting back in and drive off, because the road is higher than the grass area I could not make out what they were doing and for how long they have been there. Well I cannot find her searching in tall grass for nearly 5 hours and a area of about 300 square meters a 2m yellow and red glider is missing. Don’t laugh I even sat in a tree for 15min and nothing…….gone.

Conclusion: While searching I noted that I did not turn Ardupilot off, my reaction was full throttle and elevator. I use a proportional knob on my radio and I did not turn it not past the center position.

Most likely a rain drop fell on the forward IR sensor followed by a nose down attitude as if it was sensing cooler air and not warm Earth….is this possible?

Pick your flying area well so the plane can be monitored at all times. That was my only dodgy waypoint out of three.
The pick-up most likely saw her coming down stopped did not see me in the grass of about 1.5meters tall and sloping ground, picked her up and drove off.

I hope this could help some one else.

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Too bad you've lost your plane like this! Did you have your name on it? Remembers me I have to do that.
This is also a situation in which a ground station monitoring/(log would have been useful, at least to check if the plane went with the car or is still laying in the grass somewhere.
I hope you still have the motivation to start from new, though.
I now that’s good practise to put your name and tel number in your plane but guess what?
A tracking system is on the list for sure and yes I have not given up as in yet. I will start from scratch well almost, the need for a stable platform sort of disappeared with Co-pilot down stream.

I have one other A/C in my empty hanger now but will run with much more care next time. Like working on a solution when radio signal is lost, maybe changing the ATTiny code.
Hi Gagarien, can you explain your simulator setup a bit more please? I'm getting serial NMEA data from the port (read through Arduino serial port monitor) but how do I get ArduPilot to respond to that?
Which VSP Emulator are you using ??? Sorry again for your loss...
Jis, ek gaan eerlik wees. Dis nogal 'n erenstige kak een! Ek gaan van nou af ook versigtig wees vir die steel aksie...
I have started to work on a miniature Boerboel that you pack into your airframe for just such situations ; ) @Gagarien sorry about the plane. Drop me a message if you need anything sent from the US when you replace it sister in law is going for xmas and she could hand carry back.
What a coincidence!

I am using a Parkzone "Radian" as my eventual Ardupilot test platform. Took it up this weekend on manual control and it went down out of sight.. After about 20 mins of stomping around in the tall grass I decided to move the controls and sure enough, out of the corner of my eye, I caught the tail moving.

After this I vowed not to send the thing up without some kind of tracking. I own a copy of Microsoft "Streets and Trips" with GPS. The plan is to use XBEE radio tranmission of the raw SIRF data back to my little EEEPC. That way, if she gets lost, I can get a GPS location and PRESTO!! she's found again.


Sorry you lost her - perhaps it may be found down the line.

Do let us know
Thanks Peter I use the free ware version I think it is this one.
Cronselaar jammer ek het nog nie teruggekom na jou toe met n demo flug nie maar ek is regtig baie besig en kry nie kans om te flieg nie. Ook moet ek eers repairs doen op my nuwe airframe na n finger trouble issue tydens take off.
Graham. I assume you have FS9 running with VSP. If you are getting NMEA data in Arduino IDE from serial monitor it sounds like you are O.K. this act like your normal GPS but now disconnected you should get a blue GPS lock led.

Remember I use Ardupilot 1 but still should work with others versions as well because the only thing you do is sending Ardupilot fake NMEA data in this case from FS9.

From here I arm Ardupilot from my radio (channel 5 or what) and then fly in FS9
to see the behaviour of my ailerons and elevator as my model is trying to steer the first way point sitting right next to me on the table. I only have the FTDI cable connected to Ardupilot, the models GPS must be disconnected and the Stabilization gain turned down so that there is no external influence on servo movement besides FS9.

This I think is the very basic way to do simulation and I use it if there is new waypoints programmed to see if it will fly as expected for instance I see the elevator pitch up as I fly in FS and then I fly up as soon as the programmed alt. is reached the elevator will go to neutral if I overshoot it will start pitching down as again as expected (Why because Ardupilot does what it is supposed to do). Also for tweaking the gains etc. you can see the corresponding out put on the control surfaces and get a idea of what the aircraft might do especially if it is not enough you can see that a 3mm travel on a control surface will not steer the aircraft as an example.

If I recall correctly you are using Ardupilot v2 and with the build in stabilization it might be a problem as this will be active all the time and as you know even your body heat and movements will stuff you around. Maybe you can use Jordi’s latest code I think it got the function to disarm satbilization.

Hope this help other wise please feel free to ask.
Hey Condor can't wait to fit the Boerboel in to my airframe, Hehe. Thanks for the offer but made my own pusher A/F and got all gear to fly again. But I will let you know if I run in to a problem.

I rigged up Microsoft flight simulator to send NMEA strings over serial by adding GPSout by Pete Dowson as per this post. In configuration settings note pad I did the following:
[GPSout]
Sentences=RMC,RMA,PGRMZ,GLL,VTG,GGA,GSA,GSV (Most of not required for Ardupilot)
Port=COM10
Speed=4800

I was a little unlucky with the virtual port, I have Windows 10, I tried to use the https://www.eltima.com/products/vspdxp/. Long tormented in search of the program. And so everything turned out as you described. Thanks for the detailed description.

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