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HermannSW
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Location: Eberbach, Germany

Re: Cheap RC airplane with "outboard" Pi Zero and camera

Wed Jun 27, 2018 3:27 pm

I made many more search flights with drone, found airplane on three videos.

Today I copied out the parts of those videos that showed the airplane, did crop top left 700x360 from 1280x720 frames, slowed down framerate of 30 fps to 6 fps, concatenated the videos (all with ffmpeg) and converted to animated .gif (with gifenc.sh).

First airplane enters scene from top right to middle right hidden by leaves, then plane enters frame from middle top and leaves top left, and finally plane enters from middle top and leaves middle top:
Image


Unfortunately Iost the camera drone today as well, it flew very high, I lost sight, then it fell down and I had no idea where to search (I did hear drone hitting some tree, but had no idea of direction). I went into the wood, then smaller wood and finally near horse stable, always turning drone motors on and off. After 10 minutes I did hear the drone in trees near horse stable. I walked around the trees to ensure acoustically that drone really is somewhere in those trees and not somewhere on the ground. The small 5m diameter circle is where the airplane is in tree 20m above ground, the 10m diameter circle is where drone is in trees:
Image


Regarding my plans wrt Pi controlling drone flight I made progress in flying drone without lipo yesterday. Finally (with thick cables) I was able to fly drone tethered with 4.19V and 8.5A, allowing for unlimited indoor flight time (after I have been told repeatedly in that thread that this is not possible). I hope these are not the last pictures of my drone:
https://forum.arduino.cc/index.php?topi ... msg3786115
Image


Now I have to wait for FPV drone I did order 9 days ago during banggood super-sale for 20$ with free shipping to arrive.
The E52 will definitely allow for search of lost drone, and hopefully even allow to rescue RC airplane in tree 20m above ground:
https://twitter.com/HermannSW/status/10 ... 2218242049
Image
https://hermann-sw.github.io/planar_graph_playground
https://stamm-wilbrandt.de/en#raspcatbt
https://github.com/Hermann-SW/memrun
https://github.com/Hermann-SW/Raspberry_v1_camera_global_external_shutter
https://stamm-wilbrandt.de/en/Raspberry_camera.html

scotty101
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Re: Cheap RC airplane with "outboard" Pi Zero and camera

Wed Jun 27, 2018 4:41 pm

You are going to buy another drone, to find a drone that was lost while finding an RC aircraft.. Perhaps you need to stop flying near trees? :lol:

I do sympathize. I lost my first RC aircraft after <5 minutes of flight time as it got caught in a sudden gust of wind.
Electronic and Computer Engineer
Pi Interests: Home Automation, IOT, Python and Tkinter

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DougieLawson
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Re: Cheap RC airplane with "outboard" Pi Zero and camera

Wed Jun 27, 2018 8:22 pm

If the trees are deciduous then it's just a case of waiting for Autumn.
Languages using left-hand whitespace for syntax are ridiculous

DMs sent on https://twitter.com/DougieLawson or LinkedIn will be answered next month.
Fake doctors - are all on my foes list.

The use of crystal balls and mind reading is prohibited.

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HermannSW
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Re: Cheap RC airplane with "outboard" Pi Zero and camera

Wed Jul 11, 2018 9:11 am

Two days ago I did more excercise flights, with now 6 lipos much more flight time. I lost E52 drone two times in distant high grass, found it via drone AP Wifi signal strength shown in Android smartphone, details:
https://forum.arduino.cc/index.php?topi ... msg3800878

Yesterday I lost drone again in deep grass, with installed app Wifi Analyzer and enabled sound finding drone was easy (beep interval gets smaller while getting nearer to drone).

Finally I was able to loose drone in a tree :-(
This is frame of video taken from drone after hanging 6m above ground in tree:
Image


Luckily that location was in tree with raised blind below!
I was able to sit 3m above ground on raised blind, and with arm length and a 4m stick I was able to rescue drone:
Image


Today in the morning I did first search flights with E52 drone at group of trees with the other lost drone.
Unfortunately the E52 camera did not work well in the beginning, and finally (after more than 3*4min flight time with 3 lipos) the Android app did not even show a E52 camera video image at all :-(
Hopefully there is a simple way to fix the camera, like pressing on Raspberry v1 camera module Sunny connector ...
https://hermann-sw.github.io/planar_graph_playground
https://stamm-wilbrandt.de/en#raspcatbt
https://github.com/Hermann-SW/memrun
https://github.com/Hermann-SW/Raspberry_v1_camera_global_external_shutter
https://stamm-wilbrandt.de/en/Raspberry_camera.html

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HermannSW
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Location: Eberbach, Germany

Re: Cheap RC airplane with "outboard" Pi Zero and camera

Thu Jul 12, 2018 7:27 am

I had problems in uploading Eachine E52 .mp4 videos to youtube, youtube refused to take them.
Although .mp4 is a supported video format, youtube complained that I should use a supported format?!?!?

Yesterday I found the reason (there is an audio channel in E52 .mp4 videos) that does confuse youtube.
Since there is no microphone in E52 drone, I found easy solution in just disabling audio with ffmpeg's "-an" option.

This was first video uploaded yesterday, "Eachine E52 FPV drone free fall from more than 40m height into grass":
https://www.youtube.com/watch?v=ibJafdBGmcQ

I was able to upload the video where E52 drone ended in tree after 46 seconds using this ffmpeg command:

Code: Select all

ffmpeg -i 20180710191321.mp4 -vcodec copy -an tree_hang.mp4
https://www.youtube.com/watch?v=NMmqbc5U3Z8

At the start of the video the tree with raised blind can be seen in detail, I did not know that drone would end up there at that point in time ... I should have let speed at 30% in Android EACHINE_UFO app and not have tried 100%.

P.S:
I did order a backup E52 yesterday, for some reason it was cheaper than even during super sale last time (20$):
https://twitter.com/HermannSW/status/10 ... 0398379008
Unfortunately today it is at 29$ again.
https://hermann-sw.github.io/planar_graph_playground
https://stamm-wilbrandt.de/en#raspcatbt
https://github.com/Hermann-SW/memrun
https://github.com/Hermann-SW/Raspberry_v1_camera_global_external_shutter
https://stamm-wilbrandt.de/en/Raspberry_camera.html

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HermannSW
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Re: Cheap RC airplane with "outboard" Pi Zero and camera

Thu Jul 12, 2018 6:55 pm

I did this experiment as 2nd backup plan in case I cannot fix E52 drone camera.
I wanted to test whether Pi ZeroW+v1 camera+cable can replace E52 FPV camera board.
As easy test I just added it without removing existing FPV camera and board:
Image


86.3g E52 drone
14.0g PiZeroW+v1 camera+cable
   0.6g rubber band
-------
100.9g in total

And it really worked!
This is first time I did fly a drone in my (small) Motor Test Station (MTS).
I knew that drone is loud outdoor, indoor it feels much louder (hear into Android camera youtube video)!
This drone can carry even more easily ...
https://www.youtube.com/watch?v=7ohbj72 ... e=youtu.be
Image


P.S:
It seems that there will be another thread 'Cheap FPV drone with "outboard" Pi Zero and camera' later ;-)


P.P.S:
Automatic E52 drone liftoff with Pi backpack, played slowed down by factor of 2:
Image
https://hermann-sw.github.io/planar_graph_playground
https://stamm-wilbrandt.de/en#raspcatbt
https://github.com/Hermann-SW/memrun
https://github.com/Hermann-SW/Raspberry_v1_camera_global_external_shutter
https://stamm-wilbrandt.de/en/Raspberry_camera.html

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HermannSW
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Location: Eberbach, Germany

Re: Cheap RC airplane with "outboard" Pi Zero and camera

Sat Jul 14, 2018 9:32 am

I did some more small space flights in MTS and drone blades nearly killed the border Raspberry v1 camera cable (I lost a 1m v2 camera cable by an uncontrolled indoor drone flight before). So I taped and secured both camera cables in MTS flat to the borders:
Image


Yesterday I opened the E52 drone to have a look for the camera (problems). Only 5 little screws hold everything together:
Image


There was a small section of plastic avoiding E52 FPV camera to record downwards. Dremmel grinding disk made it go away. Now drone can record vertically downwards as well (good for lost in trees RC airplane/drone search):
Image


Today I skipped the step of finding airplane first and did try to rescue duplicate of RC airplane (airplane pulling). 24.9g+0.7g(cable)+0.6g(rubber band)=26.2g additional load was too much, drone could not lift airplane significantly above meadow:
https://www.youtube.com/watch?v=LJIlSS9 ... e=youtu.be
Image

This drone can carry even more easily ...
From previous posting we know that E52 can lift with 14.6g backpack easily, from today we know it cannot lift with more than 25g additional load.

Perhaps a 14g wrecking ball might help rescue airplane from tree ...

P.S:
Camera seems to work better now, The FPV camera antenna was directly near the three cable connector of FPV board -- I moved it away before closing the drone again, hopefully that will have eliminated the camera problems.

P.P.S:
At least a drone with (13.1g) "wrecking ball" hanging at cable is difficult to fly, ended in hedge:
https://www.youtube.com/watch?v=biWrUJk ... e=youtu.be
Image


P.P.P.S:
No-flight time for few weeks, details here:
https://www.youtube.com/watch?v=54bKzFrvFTQ
https://hermann-sw.github.io/planar_graph_playground
https://stamm-wilbrandt.de/en#raspcatbt
https://github.com/Hermann-SW/memrun
https://github.com/Hermann-SW/Raspberry_v1_camera_global_external_shutter
https://stamm-wilbrandt.de/en/Raspberry_camera.html

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HermannSW
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Location: Eberbach, Germany

Re: Cheap RC airplane with "outboard" Pi Zero and camera

Mon Jul 16, 2018 8:21 pm

As said in last posting P.P.P.S there is No-flight time until ordered blades will have arrived.

I did connect my Android to the E52 on weekend and found drone AP IP address to be 172.16.10.1.
I did "nmap 172.16.10.1" and found port 8888 open.

Today I googled for "eachine 172.16.10.1" and found this wonderful hackaday.io project:
"Controlling a JJRC H37 Elfie quad from a PC by adriajunyent-ferre"
https://hackaday.io/project/19680-contr ... -from-a-pc

All reverse engineering is done, pull_video.py and watch_video.py play quad video on PC using gstreamer, send_joystick.py controls quad from PC USB gamepad !

I will try whether E52 drone can be controlled the same way when back home on weekend, maybe a different magicword is needed in pull_video.py.

IF this works, then the Pi ZeroW I added as backpack to the E52 could
  • connect to E52 AP
  • control the drone
  • receive the .h264 video stream, and use gstreamer not to play video stream but to analyze and control drone based on video ...
    (Pi ZeroW as onboard drone pilot -- wireless, no soldering needed besides powering the ZeroW)
P.S:
"Logging into an Eachine E50S drone" is interesting as well:
http://yesuserserviceableparts.blogspot ... drone.html
https://hermann-sw.github.io/planar_graph_playground
https://stamm-wilbrandt.de/en#raspcatbt
https://github.com/Hermann-SW/memrun
https://github.com/Hermann-SW/Raspberry_v1_camera_global_external_shutter
https://stamm-wilbrandt.de/en/Raspberry_camera.html

rodizio
Posts: 43
Joined: Sat May 07, 2016 2:40 am

Re: Cheap RC airplane with "outboard" Pi Zero and camera

Mon Jul 16, 2018 10:35 pm

You may want to have a look at this before you start re-inventing everything ;)

https://github.com/bortek/EZ-WifiBroadcast/wiki
https://www.rcgroups.com/forums/showthr ... de-easy%21

https://www.youtube.com/watch?v=bfz9F9lOMm8
https://vimeo.com/user47095683/review/2 ... b621cbaf55

Image

Monitor mode works much better than Wifi in AP/Station mode. It uses Ralink and Atheros USB Wifi cards in monitor mode.


Somebody also made some code for the ESP32 connected via SPI to the Pi, but not sure how good that works:
https://github.com/jeanleflambeur/esp32 ... _broadcast

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HermannSW
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Re: Cheap RC airplane with "outboard" Pi Zero and camera

Tue Jul 17, 2018 1:55 pm

Thanks for the links, but they are on Wifi broadcast.

For "Pi ZeroW as E52 drone pilot" wifi broadcast is not needed (in the first place).

I think these are the first three simple Pi Pilot projects.
For all Pi ZeroW connects to E52 AP after some triggering, then:
  1. "Hello World": trigger "lift off" of drone (will leave drone in 1m above ground), wait X seconds and then trigger "landing"
  2. more advanced: trigger "lift off" of drone, fly forward X seconds, fly right X seconds, fly back X seconds, fly left X seconds, trigger "landing"
  3. consume E52 FPV camera .h264 video stream, split frames with help of gstreamer pipeline, analyze frames and let ZeroW make drone fly eg. along a footpath over meadow

For 2) and 3) it is important that emergency landing by triggering that through RTC (One-key down) is always possible since fully autonomous drone flight without emergency stop option is forbidden (at least in Germany).
https://hermann-sw.github.io/planar_graph_playground
https://stamm-wilbrandt.de/en#raspcatbt
https://github.com/Hermann-SW/memrun
https://github.com/Hermann-SW/Raspberry_v1_camera_global_external_shutter
https://stamm-wilbrandt.de/en/Raspberry_camera.html

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HermannSW
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Re: Cheap RC airplane with "outboard" Pi Zero and camera

Mon Aug 20, 2018 3:20 pm

HermannSW wrote:
Thu Jul 12, 2018 7:27 am
...
P.S:
I did order a backup E52 yesterday, for some reason it was cheaper than even during super sale last time (20$):
https://twitter.com/HermannSW/status/10 ... 0398379008
Unfortunately today it is at 29$ again.
The ordered E52 drone arrived in Germany during my vacation, but not at home. Instead it was held in customs office in Heidelberg and I got mail that I had to show printed invoice to get it (17.06€ or 19.51$ is quite less than the price I would have to pay tax). I knew the procedure as last year a cheap caterpillar robot was held there as well:
https://forum.arduino.cc/index.php?topic=462107.0

Besides the time and money for 40km travel to Heidelberg, going there was OK. Over the years I received >300 packets from China (aliexpress and banggood), and only two packets ended up in customs office.

What I learned today is that I only got complete drone because CE marking was not only on drone box, but on drone and RTC as well.

I did test flight with new drone in house without problems. I did try to capture drone camera video from Raspberry as described here:
https://www.raspberrypi.org/forums/view ... 3#p1352563

That did not work because the drone AP IP address is not 172.16.10.1 as with the previous E52 I have, but now it is 192.168.0.1. I did change the IP addresses in pull_video.c, but that did not work either. I will have to use ettercap tool to capture traffic between new E52 drone and Android to get working pull_video.c for the new drone.

Finally I found the reason why they did hold drone at customs office -- quadcopter for 6.50$ seems declared wrong even to me:
Image

Interesting, the packet went from China to Estonia first, and then inside EU to Germany.
https://hermann-sw.github.io/planar_graph_playground
https://stamm-wilbrandt.de/en#raspcatbt
https://github.com/Hermann-SW/memrun
https://github.com/Hermann-SW/Raspberry_v1_camera_global_external_shutter
https://stamm-wilbrandt.de/en/Raspberry_camera.html

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HermannSW
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Re: Cheap RC airplane with "outboard" Pi Zero and camera

Thu Aug 23, 2018 3:24 pm

Besides 2nd E52 drone with 4 spare blades, 4 packets with 4 spare blades each arrived during vacation time. Will prevent no-flight time for quite some time.

Yesterday evening I did another test flight over small tree, this time more than 4 minutes without issues. Because the nearby horses did not even care on the drone I did a short (6m high) flight over the horses in that video to be able to prove that horses don't care about drones:
https://www.youtube.com/watch?v=JAtV4Ps ... e=youtu.be
Image


After successful flight over 5m test tree I did a real search flight for the lost drone over high group of trees. It seems that E52 drone recording directed to ground found the lost white drone on top of 10m high tree. The white drone can be seen 4 times in the video, see youtube text for details. The animated .gif shows the 3rd part from 1:26-1:28min. White drone enters top view from right and leaves on left. E52 video is 720x576@25fps, but makeagif.com scales down to 320x256 only:
https://www.youtube.com/watch?v=axOSIz5 ... e=youtu.be
Image


For doing this kind of search videos E52 altitude hold mode is really advantageous.

Next step is the rescue part of search&rescue, but we just now get change in weather pattern and it started to rain (after being always sunny with >30°C).
https://hermann-sw.github.io/planar_graph_playground
https://stamm-wilbrandt.de/en#raspcatbt
https://github.com/Hermann-SW/memrun
https://github.com/Hermann-SW/Raspberry_v1_camera_global_external_shutter
https://stamm-wilbrandt.de/en/Raspberry_camera.html

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ab1jx
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Re: Cheap RC airplane with "outboard" Pi Zero and camera

Sun Sep 02, 2018 8:24 pm

Neat, it's easier/cheaper to read about somebody else's adventures than try it myself. I have a small drone, too small to carry a camera. It got stuck in some trees and didn't come down until spring, by then the electronics were ruined. I crash flight simulators, I wouldn't try a plane I'd spent money on.

I wonder if you could bind 2 panes together vertically and make a sort of biplane to get more lifting capability. I'm not sure how controlling them would work, maybe one could be without engines and radio, just a glider. Or scrap conventional design completely and have it emulate solar or human powered planes with long wings and small engines. I know you can buy Styrofoam in aerosol cans as building insulation, maybe you can spray it into greased molds and let it cure. Or use Balsa wood. Make a B-52 model. Flying wing? There are surveillance drones: https://en.wikipedia.org/wiki/Unmanned_aerial_vehicle

Drone technology: lightweight motors, propellers, batteries, controllers could be even more interesting if you mount those parts on a glider so lift comes from wing design instead of sheer motor power. Just looking at my dead drone here.

Oh, and you can make animated gifs with gifsicle in the Raspbian debs.

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HermannSW
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Re: Cheap RC airplane with "outboard" Pi Zero and camera

Wed Sep 05, 2018 2:09 pm

ab1jx wrote:
Sun Sep 02, 2018 8:24 pm
... I crash flight simulators, I wouldn't try a plane I'd spent money on.
I was lucky on last Sunday recce flight with drone, drone should not be above trees when lipo is drained. After 5 long seconds of drone fall through 10m high tree it ended up on ground without any issues:
Image

I wonder if you could bind 2 panes together vertically and make a sort of biplane to get more lifting capability.
I thought of similar, connecting my two planes horizontally. Have not tried yet.

Currently I figured out that my drone is capable of carrying 18.5g of backpack load.
I did a mod to replace 12.6g upper drone shell with two small wooden bars getting another 6g of backpack weight:
https://github.com/Hermann-SW/wireless- ... e#e52-mods

I need that backpack weight
  • for Pi ZeroW as onboard drone with lipo and VL53l0x laser range sensor for "constant altitude above ground mode"
  • for (1.5g) ESP-01 with servo bomb drop mechanism (>=12g in total) to increase drop weight for freeing drone from 10m high tree
Btw, today is last day you can order the E52 drone super cheap (17.59$ with free shipping, CN/0.3MP/RTC option).
I did buy a 3rd one on weekend [as backup for my backup drone ;-)]
https://www.banggood.com/Eachine-E52-Wi ... rehouse=CN

Oh, and you can make animated gifs with gifsicle in the Raspbian debs.
I know, and even better with ffmpeg.
I use makeagif.com when I have youtube video, it allows to super simply cut out what I am interested and get animated .gif

I did much with gifsicle in the past.
Here you can challenge your browser with 30 animated .gifs in a single page (Shortest construction tasks map):
http://stamm-wilbrandt.de/chess/en/sct_map.html
https://hermann-sw.github.io/planar_graph_playground
https://stamm-wilbrandt.de/en#raspcatbt
https://github.com/Hermann-SW/memrun
https://github.com/Hermann-SW/Raspberry_v1_camera_global_external_shutter
https://stamm-wilbrandt.de/en/Raspberry_camera.html

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ab1jx
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Location: Heath, MA USA

Re: Cheap RC airplane with "outboard" Pi Zero and camera

Wed Sep 05, 2018 5:04 pm

HermannSW wrote:
Wed Sep 05, 2018 2:09 pm
I wonder if you could bind 2 panes together vertically and make a sort of biplane to get more lifting capability.
I thought of similar, connecting my two planes horizontally. Have not tried yet.
No, it needs to be vertically, at least for what I'm thinking of. Not even another plane but another wing. https://en.wikipedia.org/wiki/Lift_(force) My father used to make boomerangs by cutting them out of plywood and sanding the leading and trailing edges by eye. I've made windmill blades (which have a lift pointing downwind) by using a spreadsheet.

You could go to a building supply store and get a piece of styrofoam insulation a little thicker than your airplane wings, then mount that probably above the original wing like a biplane. I don't know the best way to shape it, a very sharp knife like an xacto or razor blade maybe, or a hot knife like on a soldering iron. It's going to tend to crumble, you want a smooth surface so the air will flow over it. The leading edge should be blunt, the trailing edge comes to a point in the back. Molding it yourself might give you more control but then you need to build molds and get the wing out afterward. A Dremel tool with its high speed might help.

Image

There might be a better material, seems like hobby shops sell a kind of lightweight plastic foam that's easier to shape. Never got into that stuff. But if you can get more lift you can carry more stuff. And the motors and controller can stay the same. Windmillls: http://www.scoraigwind.com/

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HermannSW
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Re: Cheap RC airplane with "outboard" Pi Zero and camera

Wed Sep 05, 2018 6:30 pm

Thanks for all that information, I will try after drone bromb dropped (hopefully) lost drone in 10m height and lost airplane in 20m height, and having Pi ZeroW autonomous fly the E52 drone as onboard pilot ...

What I meant by horizontally was joining my two airplanes at the wings, and fly both airplanes concurrently. In theory this should double backpack capacity (the small RC airplane weight is 23g, and it did lift and fly with 40g incl. Pi Zero and camera).

Interestingly Stratolaunch seems to follow a similar concept, they have the worlds widest airplane (117m) now:
Image
https://hermann-sw.github.io/planar_graph_playground
https://stamm-wilbrandt.de/en#raspcatbt
https://github.com/Hermann-SW/memrun
https://github.com/Hermann-SW/Raspberry_v1_camera_global_external_shutter
https://stamm-wilbrandt.de/en/Raspberry_camera.html

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ab1jx
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Re: Cheap RC airplane with "outboard" Pi Zero and camera

Wed Sep 05, 2018 7:34 pm

Yeah, maybe. The Solar Impulse 2 only had 1 wing too. https://www.smithsonianmag.com/innovati ... 180968000/
over_gg_bridge_sf.jpg
over_gg_bridge_sf.jpg (87.35 KiB) Viewed 9839 times

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HermannSW
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Re: Cheap RC airplane with "outboard" Pi Zero and camera

Sat Oct 13, 2018 8:08 pm

Updates on drone/airplane rescue activities.

I made good progress in adding ESP01s powered (because that microcontroller has Wifi and weight 1.5g only) payload servo drop mechanism (SG17 servo weight is 1.7g only!) to 2nd of my three Eachine E52 drones. So yesterday I took the third E52 and made surveillance flight just to confirm white drone (lost while searching for lost yellow RC airplance) is still at top of tree where I found it. I did not do a safe flight and the drone went into the tree. I was not that lucky as the last time that happened, where drone took 5 long seconds to completely fall through tree and end at ground. This time it did fall some time, but then remained in tree :-(

Here is the updated "lost" image, colored dots are locations of yellow RC plane, white drone and red E52 drone:
Image


Today a friend helped me, we took my 7m ladder and his 4m stick with hook at the and and went to the trees. He made ladder stay secure, I did climb up 6m, adding 2.30m of me with stretched out right arm, and 4m stick I did shake out all tree arches I could reach in the area of the tree where I had seen movement yesterday when powering up transmitter, doing calibration and then autostart. So not found or rescued, and what we know its location is higher than 12m from ground in the tree.

After I was safely on ground again, my friend did move away some meters, took a photo of the tree (that I thought to be not much higher than 10m high) and used Timber Tree Height Estimator. That proved my tree height guesses to be totally wrong, he measured 22m :-(

So red E52 drone sits in tree in height 12-18m, white drone on top at 20-22m, and yellow airplane tree is even higher, so it seems to sit in 25-30m height from ground ...

I have videos from all three E52 drones that I bought at different low price times with free shipping on banggood.com:
June 17.34€
July 17.06€
Sep 16.09€ (17.99$)


I did know that 1st E52 has 0.4MP camera and does 720x576@25fps videos (https://github.com/Hermann-SW/wireless- ... ideo-facts).
I used "ffmpeg -i ... -hide_banner" to find out video information for the others from videos taken by them.
2nd E52 has 0.3MP camera and takes 640x480@30fps videos.
3rd (lost yesterday) has 2.0MP camera and takes 1280x720@17fps videos.

I lost drone yesterday because I did fly way too low. Camera was directed to ground, there would have been a much easier and safer way to do surveillance flight: start on meadow, climb much higher than the trees, move over tree until seeing white drone live on Android screen and then slowly move drone downwards making sure not to get too near to the tree.

Last night I made big progress with 2nd drone and completely mounted payload drop system.
Details in this posting (and the thread postings before):
https://www.esp8266.com/viewtopic.php?f ... 604#p78604

This is first drone camera video showing remote payload drop onto target 17.5cm below:
Image Image
Image

As some people pointed out, autumn definitely will help in getting clear view on red E52 drone lost yesterday, and the yellow airplane only seen in 3 videos from > 50 videos.


P.S:
photo used for tree height estimation; red E52 drone somewhere in top half left of main arch from here:
Image
https://hermann-sw.github.io/planar_graph_playground
https://stamm-wilbrandt.de/en#raspcatbt
https://github.com/Hermann-SW/memrun
https://github.com/Hermann-SW/Raspberry_v1_camera_global_external_shutter
https://stamm-wilbrandt.de/en/Raspberry_camera.html

User avatar
HermannSW
Posts: 5172
Joined: Fri Jul 22, 2016 9:09 pm
Location: Eberbach, Germany

Re: Cheap RC airplane with "outboard" Pi Zero and camera

Sat Nov 24, 2018 9:12 pm

HermannSW wrote:
Thu May 24, 2018 5:41 pm
...
So here after 3 frames the "same" scene appears again. I wanted to be sure and used 640x150_s tool that records every other line/column only and therefore captures with 1007fps as well. Because of the different "capturing position/time after framestart" pair this video is much better to see that indeed the propeller moves 1/3rd of a round per frame (coarser in both directions, but the 640x150 frame shown correctly represents the 640x150 from camera fov covered):
Image


So now we can do the math and see more than 20,000rpm for the propeller:

Code: Select all

$ bc -ql
1007/3
335.66666666666666666666
1007/3*60
20139.99999999999999999960

P.S:
Just in case my interpretation is wrong and the propeller does not 1/3rd of a round per frame, but 4/3rd, then propeller rpm would be 80,000
I did buy a digital laser photo tachometer for less than 8$, and it did travel from China to Germany in 19 days only:
https://www.aliexpress.com/item/Digital ... 90838.html

I was able to determine propeller RPM immediatly after I put a small part of reflective mark onto one side of one propeller. After I fully loaded the airplane lipo I began to record a video, too few hands but finally it worked after some tries:
https://www.youtube.com/watch?v=vYNjfm1 ... e=youtu.be
Image

Maximal reading was 18233 rpm and constantly dropping slightly. I looked the 1fps animated .gif again and saw that after 3 frames the white marker was not exactly on same place. 3 frames do a little less than 1 complete propeller turn, so the propeller speed shown is less than the 20140 computed above. Most importantly now it is answered that indeed a single frame of 1007fps video captures roughly 1/3rd of a round and not 4/3rd (the digital tachometer measurement range is 2.5-99999 rpm).
https://hermann-sw.github.io/planar_graph_playground
https://stamm-wilbrandt.de/en#raspcatbt
https://github.com/Hermann-SW/memrun
https://github.com/Hermann-SW/Raspberry_v1_camera_global_external_shutter
https://stamm-wilbrandt.de/en/Raspberry_camera.html

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ab1jx
Posts: 887
Joined: Thu Sep 26, 2013 1:54 pm
Location: Heath, MA USA

Re: Cheap RC airplane with "outboard" Pi Zero and camera

Sat Nov 24, 2018 9:33 pm

Ion propulsion, that's what you need. Measure KV instead of RPM. :)
https://news.mit.edu/2018/first-ionic-w ... parts-1121 and
http://news.mit.edu/2013/ionic-thrusters-0403

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HermannSW
Posts: 5172
Joined: Fri Jul 22, 2016 9:09 pm
Location: Eberbach, Germany

Re: Cheap RC airplane with "outboard" Pi Zero and camera

Tue Aug 13, 2019 8:29 am

HermannSW wrote:
Wed Sep 05, 2018 6:30 pm
Interestingly Stratolaunch seems to follow a similar concept, they have the worlds widest airplane (117m) now:
Image
People have stretched this concept to the limit !
"Flex 9 is an airplane made out of 9 smaller airplanes connected at wings"
https://www.youtube.com/watch?v=mrJgoQz ... =hootsuite
Image
https://hermann-sw.github.io/planar_graph_playground
https://stamm-wilbrandt.de/en#raspcatbt
https://github.com/Hermann-SW/memrun
https://github.com/Hermann-SW/Raspberry_v1_camera_global_external_shutter
https://stamm-wilbrandt.de/en/Raspberry_camera.html

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HermannSW
Posts: 5172
Joined: Fri Jul 22, 2016 9:09 pm
Location: Eberbach, Germany

Re: Cheap RC airplane with "outboard" Pi Zero and camera

Sat Oct 17, 2020 12:19 am

bAfter I lost 1st airplane, 2nd airplane with Pi0 and v1 camera identified where to look and I had two airplanes.
Then I lost the 2nd airplane in very high tree, and two drones while searching for plane and 1st lost drone.
Today I realized that I still have the airplane with cabling for powering Pi0.

What I learned quite some time ago is, that an airplane can stay much longer in the air with the same amount of energy (lipo) than a drone.

What I learned with my raspcatbot is that frames captured with rolling shutter camera with vibrations of moving caterpillar robot (or drone or airplane) are horrible
viewtopic.php?f=37&t=267999&start=25#p1634711

and that a global shutter camera removes all the issues:
viewtopic.php?f=37&t=267999&start=25#p1636118


In the very first posting of this thread the weight of airplane plus Pi0 plus v1 camera plus cable was 38.2g.
Pi0W with headers and (25.99$) ov7251 0.3MP monochrome global shutter camera weight 43.4g is only 5.2g more than before:
20201016_154448.20%.jpg
20201016_154448.20%.jpg
20201016_154448.20%.jpg (31.79 KiB) Viewed 2825 times

I was able to reverse engineer the wireless protocol of Eachine E52 drone camera and Android app, and let Pi retrieve the video for version v1 of the firmware. Unfortunately I was not able to reverse engineer version v2 of the firmware:
https://github.com/Hermann-SW/wireless- ... -e52-drone

Plan is to let PioW fly the airplane autonomously by cnnecting to the two plane motor controllers the wireless receiver drives.
Pi0W captures 320x240 monochome frames at 204fps framerate like I did with raspcatbot already.
Pi0W analyzes frame, identifies e.g. footpath in the fields and flies along.
I need an emergency channel for getting airplane down in case of e.g. program malfunction.
I will use heartbeat signal sent to Pi0W on the plane from ground, when heartbeat stops, Pi0W turns off motors and plane will land.
[ Nice side effect of turning off heartbeat signal from ground is, that control of the airplane via wireless control works then.
This allows to fly airplane to some "start" position and then trigger automatic flight by turning on heartbeat signal again. ]


Important step is to verify that 43.4g weight airplane can still fly (150mAh lipo was part of that weight).
I will do that after my physical rehab begin of December.

Next step will be to fly and capture monochrome global shutter videos with ov7251 camera looking down, and see whether footpath and other stuff can be seen by me, and later by an algorithm. Should be possible as the footpath in this this selfie of me taken with v1 camera 3 years ago:
Image


Before that, finding out how to connect the Pi0W with the airplane wireless receiver motor controllers works can be done.
And I need to determine how slow/fast affects propeller rotational speeds.
And how turning left/right with remote control affects rotational speeds.

I will measure voltages while plane will be fixed by soldering 3rd hand.
I will determine rotational speeds of both propellers at the same time with HQ camera and diy highspeed flash as done in this posting:
viewtopic.php?f=43&t=284108&p=1738021#p1738021
Because the flashes will be triggered for each 1012x760 frame captured at 80fps, single video will reveal all propeller speeds for slow, fast, left, right, ...


What I did today is to git clone Arducam MIPI_Camera repo and build according instructions:
https://github.com/ArduCAM/MIPI_Camera/tree/master/RPI
I took a raspi2png screenshot of the Pi0W connected to HDMI monitor while running this command:

Code: Select all

pi@rpi01:~/MIPI_Camera/RPI $ ./arducamstill -t 0 -m 5 -awb 1 -ae 1 
Open camera...
Found sensor ov7251 at address 60
mode: 0, width: 640, height: 480, pixelformat: Y10P, desc: (null)
mode: 1, width: 640, height: 480, pixelformat: Y10P, desc: (null)
mode: 2, width: 640, height: 480, pixelformat: GREY, desc: (null)
mode: 3, width: 640, height: 240, pixelformat: GREY, desc: (null)
mode: 4, width: 640, height: 120, pixelformat: GREY, desc: (null)
mode: 5, width: 320, height: 240, pixelformat: GREY, desc: (null)
index: 0, CID: 0x00980914, desc: V4L2_CID_HFLIP, min: 0, max: 1, default: 0, current: 0
index: 1, CID: 0x00980915, desc: V4L2_CID_VFLIP, min: 0, max: 1, default: 0, current: 0
index: 2, CID: 0x00980911, desc: V4L2_CID_EXPOSURE, min: 0, max: 65535, default: 512, current: 2157
index: 3, CID: 0x00980913, desc: V4L2_CID_GAIN, min: 0, max: 255, default: 16, current: 16
index: 4, CID: 0x00981901, desc: V4L2_CID_ARDUCAM_EXT_TRI, min: 0, max: 1, default: 0, current: 0
Can't open the file
mmal: Failed to fix lens shading, use the default mode!
Failed to set focus, the camera may not support this control.
Failed to set focus, the camera may not support this control.
Start preview...
Current mode: 5, width: 320, height: 240, pixelformat: GREY, desc: (null)
Mono camera does not support automatic white balance.
[Framerate]: 01 pfs, [Exposure]: 0032, [Focus]: 0000,[Rgain]: 0000, [Bgain]: 000
[Framerate]: 23 pfs, [Exposure]: 0032, [Focus]: 0000,[Rgain]: 0000, [Bgain]: 000
[Framerate]: 26 pfs, [Exposure]: 0032, [Focus]: 0000,[Rgain]: 0000, [Bgain]: 000
...
320x240 preview image is scaled bigger in preview:
snapshot.png.jpg
snapshot.png.jpg
snapshot.png.jpg (84.94 KiB) Viewed 2825 times


Just verified that Pi0W and ov7251 camera can capture 320x240 frames at 204fps as well:

Code: Select all

pi@rpi01:~/MIPI_Camera/RPI $ ./raw_callback.320x240 
Open camera...
Found sensor ov7251 at address 60
Setting the resolution...
...
Start raw data callback...
Total frame count = 2043
TimeElapsed = 10.000161
Stop raw data callback...
Close camera...
pi@rpi01:~/MIPI_Camera/RPI $ 

Only change:

Code: Select all

pi@rpi01:~/MIPI_Camera/RPI $ diff raw_callback.c  raw_callback.320x240.c 
37,38c37,38
<     width = 1920;
<     height = 1080;
---
>     width = 320;
>     height = 240;
pi@rpi01:~/MIPI_Camera/RPI $ 
https://hermann-sw.github.io/planar_graph_playground
https://stamm-wilbrandt.de/en#raspcatbt
https://github.com/Hermann-SW/memrun
https://github.com/Hermann-SW/Raspberry_v1_camera_global_external_shutter
https://stamm-wilbrandt.de/en/Raspberry_camera.html

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Gavinmc42
Posts: 6616
Joined: Wed Aug 28, 2013 3:31 am

Re: Cheap RC airplane with "outboard" Pi Zero and camera

Sat Oct 17, 2020 12:53 am

Cool, Global shutter cameras are going to make a difference.
Looks like three sizes available too.
Mono so can be used with IR .

1M Pixel with M12 lens :D

Thanks for bring me up to speed.

Got some other stuff too.
Drop in replacement sensor for my broken, bad focused V2 :P
Even M12 version.
I'm dancing on Rainbows.
Raspberries are not Apples or Oranges

User avatar
HermannSW
Posts: 5172
Joined: Fri Jul 22, 2016 9:09 pm
Location: Eberbach, Germany

Re: Cheap RC airplane with "outboard" Pi Zero and camera

Sat Oct 17, 2020 7:41 pm

Gavinmc42 wrote:
Sat Oct 17, 2020 12:53 am
Cool, Global shutter cameras are going to make a difference.
Looks like three sizes available too.
Mono so can be used with IR .
0.3MP/1MP/2MP, all mono, 2MP in color as well.
1M Pixel with M12 lens :D

Thanks for bring me up to speed.

Got some other stuff too.
Drop in replacement sensor for my broken, bad focused V2 :P
Even M12 version.
The 1MP ov9281 monochrome global shutter camera is available for 29.99$ without M12 166° lense, or for 41.99$ with M12 lens (130° normal or NoIR, or 70° NoIR):
https://www.uctronics.com/catalogsearch ... /?q=ov9281

I did capture 1MP 1200x800 frames of airsoft pistol pellets inflight without bright flash with that camera on our terrace, sunlight is so bright:
viewtopic.php?f=43&t=267563&p=1642029#p1642029
Image



For my raspcatbot caterpillar robot/RC airplane self driving/flying projects I prefer the 25.99$ 0.3MP monochrome global shutter ov7251 86.5°camera (I have the normal, there is a NoIR version as well):
https://www.uctronics.com/catalogsearch ... /?q=ov7251

And I do not use maximal 640x480 frame size but 320x240 for two reasons:
higher framerate (204fps), and lower number of pixels to analyze per frame

Pi0W analyzes frame, identifies e.g. footpath in the fields and flies along.
Maybe an easier first "hello world" autonomous flight problem would be "fly circles around a free standing tree".
From one of the first full HD 30fps videos in this thread
https://www.youtube.com/watch?v=bo0iMjMv46w
this is part of a youtube frame, and it shows the free standing, only 5m high tree I used for drone rescue flight training before. The horses are only seldom in that area:
training_tree.png.jpg
training_tree.png.jpg
training_tree.png.jpg (32.54 KiB) Viewed 2760 times

v1 camera had 65° FoV, will be interesting how ov7251 86.5° (diogonal) FoV view will look like, especially with intentional 320x240 frame size.

need an emergency channel for getting airplane down in case of e.g. program malfunction.
I will use heartbeat signal sent to Pi0W on the plane from ground, when heartbeat stops, Pi0W turns off motors and plane will land.
[ Nice side effect of turning off heartbeat signal from ground is, that control of the airplane via wireless control works then.
This allows to fly airplane to some "start" position and then trigger automatic flight by turning on heartbeat signal again. ]
I remembered that I did solve this problem for raspcatbot already, although I did not use it lately for raspcatbot because most highspeed inhouse runs were done in cable car mode:
viewtopic.php?f=37&t=267999&hilit=raspc ... 5#p1634073

I will use my "Wifi joystick with display" for this, especially only its red dead-man button.
The ESP32 code can be found here, as well as "select()/read()" code used on Pi3A+ for raspcatbot for checking whether heartbeat is still alive:
https://esp32.com/viewtopic.php?f=19&t= ... 291#p57291
Image
https://hermann-sw.github.io/planar_graph_playground
https://stamm-wilbrandt.de/en#raspcatbt
https://github.com/Hermann-SW/memrun
https://github.com/Hermann-SW/Raspberry_v1_camera_global_external_shutter
https://stamm-wilbrandt.de/en/Raspberry_camera.html

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Gavinmc42
Posts: 6616
Joined: Wed Aug 28, 2013 3:31 am

Re: Cheap RC airplane with "outboard" Pi Zero and camera

Sun Oct 18, 2020 5:51 am

And I do not use maximal 640x480 frame size but 320x240 for two reasons:
higher framerate (204fps), and lower number of pixels to analyze per frame
It seems most CV stuff is done at about that size.
There seems to be no benefit when using higher res and the larger data sets slows things down.

Omnivision says, looks interesting for MV, low power modes, hmmm
QQVGA (160x120) at 360 fps with binning and skipping
You might want to look at Pixart sensor to avoid collisions :lol:
Openbot has some interesting software that runs of smart phones, port to the 4 core Pi's?
I'm dancing on Rainbows.
Raspberries are not Apples or Oranges

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