Mayday! Mayday! I tested the FPV system on the Raptor140B, with nearly disastrous results. Luckily, the APM was onboard to save the day!
I added the 400mw 1.3Ghz FPV transmitter to the 140B, and took it for a test flight. Right after take off I had significant control issues, and barely recovered the airplane. Thinking it may have been the flight controller, and wanting to determine the cause while the same circumstances were available, I double checked all connections and systems, and flew the aircraft again.
Again, it had significant control issues, even in manual modes. Luckily, the APM flight controller was able to safely loiter the airplane overhead while I determined that indeed the Turnigy 9x transmitter was no longer able to safely control the airplane.
This required me to create a mission mid flight, update the mission, update flight parameters, and attempt an autolanding, the first time I've tried this feature.
Watch the find out the results!
-Trent
Safety Statement: To maintain safety, I prepared by doing many thing things including:
-obtaining personal permission from a vast majority of property owners (I couldn't reach all of them)
-maintained a continues watch for full scale aircraft, and;
-maintained direct control of the aircraft for the majority of the flight
-this airplane and system has OVER 1,000 MILES of perfect performance, with 90% of it autonomous with this exact set up. It has been tried and proven many, many times, including over 200km of cross country flights
-the autopilot was programmed to continue to fly after a signal loss, which has been tested and proven to perform many, many times
-the flight was over a very open and low populated area, with 99%+ of the area being open fields or trees
-the altitude read over 120m, but elevation increased during flight as I took off out of a low valley. True AGL for the flight is 100-120m.
-avoided all airports and populated areas.
-I've flown at this location 3-5 times a week for the last year. I know it very, very well.
-I conducted test flights with the new set up that I did not show during the video to confirm stable performance
Raptor 140b+ Stats:
Weight: 2280g
Max Flight Time: 70min
Max Range: 97km
Stall Speed: 35kph
Cruise Speed: 90kph
Max Speed: 135kph
Radio Range: 1.5km
Energy Carried: 167wh (15,000mAh at 11.1v)
Drive Power: 850w
Total Flight Time on Craft: 7.0 hours
Total Flight Distance on Craft: 498km
The equipment used---
Raptor 140 airplane: http://store.mygeekshow.com/product-p/raptor-140-kit.htm
Radio Tx: ParkeFlyer Turnigy 9x Tx: http://parkeflyer.com/
Telemtry: 915mhz 100mW 3DR http://store.3drobotics.com/products/3dr-radio-telemetry-kit-915-mhz
Laptop: Compaq Presario CG57
GPS Dongle: http://www.amazon.com/gp/aw/d/B000PKX2KA/ref=redir_mdp_mobile?redirect=true&ref_=oh_details_o02_s00_i00
Flight Controller: APM2.6 https://store.3drobotics.com/products/apm-2-6-kit-1
Reciever: 6ch FlySky http://www.hobbypartz.com/79p-r6b-receiver.html
Telemtry: 915mhz 100mW 3DR http://store.3drobotics.com/products/3dr-radio-telemetry-kit-915-mhz
Battery: (3) 5.0Ah 20C Lipo: http://store.mygeekshow.com/product-p/5ah-3s-battery.htm
ESC: 60A Brushless http://store.mygeekshow.com/product-p/60a-esc.htm
Motor: 3542 1450kv brushless http://store.mygeekshow.com/product-p/1450kv-3542-motor.htm
Prop: 10x7 Carbon Fiber Folding http://www.hobby-lobby.com/10x7_carbon_fiber_cam_blade_798_prd1.htm
Servos: 11g digital http://hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=42620
Onboard camera: http://www.ebay.com/itm/16-V2-Lens-D-808-Key-Chain-Video-Camera-/380627482427?#ht_5755wt_1149
Learn More:
Raptor Details: http://www.mygeekshow.com/theairplanes/Raptor140.html
USA Trip Details: http://www.mygeekshow.com/usatrip/
Follow the Show:
Website: http://www.mygeekshow.com
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Twitter: http://twitter.com/mygeekshow
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Skype: MyGeekShow
UStream: http://www.ustream.tv/channel/mygeekshow
Filmed, Edited, Produced and Published by Trent in Arkansas, USA
Comments
@Hugues, I'm not sure. For close range flying 2.4 control and 5.8 video is totally acceptable. 2 miles on that setup is not much of a challenge with a CP cloverleaf and helical diversity setup. Honestly, lets face it: the days of 20km out and back FPV are soon gone.
I think what folks are eluding to here are C2 links and the WRC is making them above 5 Ghz Very soon all the stuff folks are playing with at the moment will be very illegal. Not FAA illegal, FCC and your local country illegal.
1.2 is very close to current nav frequencies and a sign of poor airmanship to use.
also, dont forget to use the telemetry logs when adding new equipment. For example, I had an issue when mounting my video Tx too close to the APM. There was enough RF energy to interfere with my magnetic heading sensor in the APM.
if you power on the system, let it run for a little while, then plug in the video Tx power and let it run for a while, once you download the logs you can see if the video transmitter is affecting anything. Be sure to check the magnetic sensor and the GPS HDOP. Both are critical.
5.8 is definitely the way to go. you dont have to worry about harmonics, and the range on 600mw is more that adequate. Range is a battle that is won with antennas anyway. I highly recommend investing in some good circular polarized antennas...
My current setup is 433 UHF for control, 900Mhz for telemetry and 5.8Ghz for video.
Having the APM on board is a safety net that wasn't there when I first started. Be careful though... while it can save your bacon in times like this, it can also lull you into a false sense of security. Nothing beats a preflight checklist and a true range check when something new is added.
It also didnt seem that you have the failsafe set on your receiver. This is also a critical thing you need to check. Normally have RTL set with a switch on my transmitter and the failsafe on the receiver is set to normal cruise settings (all sticks centered) with RTL switch engaged. You can test this on the ground before arming by turning off the transmitter. The APM should switch to RTL mode. If not, then your failsafe is not working and you could have a flyaway. Most modern 2.4 receivers will just output the last known PWM values unless failsafe is set.
Looks to me that @Trent "controlled" his aircraft at 900 MHz.
Ted, I second this idea of using the lowest freq for control. What would you then use for telemetry then, if 433 MHz is used for control (as we can't use 900 freq in Europe)
Your control frequency should always be the lowest frequency on your ship. Therefore is you use 2.4 ghz, 5.8 has to be your video. I'd recommend a UHF system. Exciting video, love your series.
Just go to 5.8 GHz and don't look back. I'm just getting started in FPV, and this seemed like the best option for us. 1.2/1.3 is horrible because it also can kill the GPS signal.
I've used a 200 mW 5.8 system out to 300m, and even behind a treeline, with nothing more than the CP antennas, and a diversity Rx monitor. I didn't think it was possible to go behind a treeline with 5.8, but it did. So it does just about everything I want so far.
Your excitement and energy makes your videos fun to watch. I'm glad you got it down in one piece. This shows how things can go wrong, and how some ingenuity can save the day.
1.3Ghz is HAM band. To transmit video you must: have a HAM license and display your HAM sign call letters in the video usually embedded in the OSD text. I have also found that high power 1.3GHz can interfere with GPS (1.4GHz) so watch out.
Bottom line, there are plenty of other frequencies to use, I suggest NOT using 1.3GHz. Choose either 900, 2.4 and 5.8.
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