First is anybody else flying the X8?  

I bought mine RTF to do Aerial vids with a Hero 3D rig.  I bought an brushless RCTIMER ASP 2-Axis Nex-GH5 .  It was fairly easy to get a sound install and finally figure out how to power up the gimbal and it's seems to be working fine.  I had to add landing pads to the base of the X8 landing gear to give the Gimbal and camera space for landing.

I have begun flight testing the rig and found the simply to adjust the COB on the x* I hang two batteries as far aft as I could.  they were two 3s 4200 mah. My early flights were short and damaging.  As I have now learned to view the flash logs and T logs I could see that I had a serious power deficiency and he throttle mid point was way low.  I have to run the throttle hover mid point at 600 to get loiter stable.  Is that too high? I found I was running routinely at 70-80 amps with the 3s batteries that came with the machine. Flight time was barely 4-5 minutes was precipitous drop at the end.

I decided to try a 4s battery 4000mah and have noticed some improvement in throttle levels and stable fllght times. I think I am on track with the larger 4s for the added weight but I'd love to hear other ideas.  One thing I have found out is it's easy to kill a good battery if you run the voltage below levels and I've done it to three already when I try to get the maximum flight time.

I still have no confidence in this rig for a mission.  I have been hover around the backyard. Trying to get it stable and get predictable flight times.  When the juice runs out this thing drops like a stone and unlike my Phantom there is no real warning time.

I can only conclude I need more and larger batteries to get my flight times up.  I am running the stock rig shipped by 3D Robotics.

Is there a mentor out there that would tolerate my incessant question while I try and master this very hard to fly rig?

I attach an image of the present set up with my ears open for better ideas.

Jamie

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Ok. 4S gives you more power. Larger mAh gives you more flight time. LiPo batteries die under 3 volts per cell. Max charge your voltage is 4.2 per cell. I recommend you get a battery buzzer to alarm you when you are ar low voltage. Below are some links for the buzzer.

LiPo Buzzer

http://www.ebay.com/bhp/lipo-buzzer

http://www.hobbyking.com/hobbyking/store/__34120__Hobbyking_2_8S_Ce...

You should get telemetry setup and you should read and configure fail safes. Loss of radio signal should RTL. Low battery should and fail safe should land.

When you practice stay low until can fly well. Learn to fly in stabilize mode. I mean learn really well. If all else fails you need flight skills to recover when the automatic fail. After stabilize you should work altitude hold then loiter then auto mission. You need to make sure everything work in one mode before moving to the more advance modes.

The wiki is quite good. You should read and study it. It has a wealth of info.

Remember have fun and fly safe.

P.S. There are only 2 types of pilots. Those that have crashed and those yet to crash.

Jamie, I'm about to get a 3DR X8 with the ASP 2-Axis. I will appreciate any advice you can give me about the batteries and the Gimbal. I'm planning to use a Canon SX280 or a NEX.

Ivan,

I can't recommend the 3DR X8 yet.  I have been very frustrated with the lack of tech support, my e-mails have gone unanswered.  The 3s batteries it ships with are not adequate for larger payloads, at least 4s is needed. Since I need at least 10 minutes flight time and my X8 consumes from 60-80 plus amps to hover. I am testing two 5000 mah 4s 40c batteries now, but they add considerable weight. My payload with gimbal and camera is over 720 grams.  

The landing gear are too short for the ASP 2 -Axis and 3DR Robotics does not supply anything longer. I rigged something out of1/2"  CPVC pipe and swim noodles, this adds weight also.  You can't even buy some parts like replacement landing gear which break easily .  The design is fragile, I have gone through a complete set of props and three motors trying to learn to attain stable flight.

The design precludes larger props because of the motor spacing, I think larger props and torquier motors might be more efficient and stable. 

You will need to re-calibrate the throttle to 60% or more or loiter will not work. I am still trying to figure out a rig I can use to tune the rest of the PIDs, I am certainly not going to hold it in my hand.

I am spoiled by my two DJI Phantoms, indestructible, easy to config, and with the Gopro 3 and gimbal  flies like a dream with plenty of flight time on it's standard battery and with a FPV fat shark rig.  I would say so far the DJI fight controllers are more reliable and easier to use.  Maybe after another 40 hours of testing, I will change my mind.

I want 3D Robotics to work, it is and American company started by young and feisty entrepreneurs.  So I am persisting for now.  They have a long way to go in service and support.

I am still hopeful, but not convinced.

I've had the x8 for a few months now and have yet to use it in a good capacity. It eats the 4200 3s battery's like candy and the APM is totally useless to get stable. I have considered this a big loss and gone over to steadidrone ei8ht.
Since there is no help to be found with APM I will be switching to Naza v2 to se if I can make the x8 sellable. Never going open source on expensive equipment again and not buying 3dr.

I fly a Steadidrone QU4D with APM and its no issue.

There are those who are lucky but APM is not even close to Naza or Wookong in reliability and a quad is a lot easier to calibrate and operate compared to the x8.
I bought the x8 to start operating something more than a gopro but it hasn't got lift power or endurance for anything bigger and then I get better value from even the little phantom.

I wish I wasn't confirming what you've said, but the X8 seems to be underpowered, an energy hog, and does eat batteries.  I have accidentally killed two brand new ones by running the motors too long. I wish it had the simple feedback of the blinking LED like a Phantom, which tells you in plenty of time when to land by blinking red flashes.  It has all these flight modes I don't need and the one I do, which is a (GPS Lock) Loiter mode with full control of pitch, yaw. roll and throttle does not exist, why? Stabilize mode is a super pain in any breeze at all, but I can't kill throttle in any other mode.

Again I keep reading that tuning the PIDs will solve all my problems. More when I resume test flights, but I am skeptical. Is the 3DR X8 design a lemon?  Who is getting good results?

I use an X8 as a sensor platform, for research work, about 2 months now, and it works great!

Stock 3s gives me about 10 minutes on one, about 15 on two.

 

APM is currently easier to interface with then an PX4 (and I don't want to give up VS)

X8 flew well out of the box, inside and out.

Only thing I did, flight wise, was adjust GPS PID values as per 3.0.1 release thread.

I bought the X8 for the simple reason of a back up motor, as I have lost enough $$ in the past having a ESC, prop, motor, or whatever fail.

 

One of our first test was flying without one prop, and it did well.

 

Never tried a true 8, or Hexa, I have Quads, and Bi-Quad (Two pairs of articulated motors) and the X8 is pretty much at same level for endurance / payload.

 

If you guys are really getting that much more performance in real life, maybe I should try other air frames?

 

 

 

Just turn voice on, in MP, gives me a nice verbal notice when batteries are low, in case I'm not watching my OSD, in my FatShark.

This is a 3DR X8 with tock landing gear, what's the payload? My overall weight is 2.88 kg with gimbal and camera, what's yours?  I can't get more than 5 minutes out of a single 3s as shipped.  What amps do your motors draw at a hover?  Did you have to recalibrate throttle? Mine was set at 30% way too low to maintain a hover, I had to raise it to 65%.  Can you share your config file or a screen shot? 

That's great if you want to schlep your laptop everywhere you go in the field and stand next to it to fly. Did you use the shipped transmitter with Fat Shark?  I got a 1.2 mhz and the FatShark is 5.8mhz. What do you have your voltages set to warn and for RTL?  Could you share any videos or photos of your rig?

I have the stock voltage / amp values as warning.

Yes, I have a windows 8 tablet, attached to my radio, so it does "go everywhere" with me :)

My payload is about 1 kg

I have 5.8 video link that came with the X8

I can share a config file tomorrow if you wish, not sure about amps, would need to look at logs. Given early tests gave us the flight time we needed, I never took note of amps

Here she is sitting on my desk a few weeks ago.

(Yes, that's my daily ride in the back ground....well it was, likely not get it back out ,till next spring)

 

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