Aeronavics / Droidworx Flight Time assistance needed.

[rdalemercer]

Dale,

There is a reason that the cutoffs are based on voltage rather than mah. Every lipo battery runs within a window. Lets say this is an 8000Mah pack. The over all amp load is going to determine how much mah you can draw. If you are running a high amp draw flight application the pack will sit under load at a lower voltage than if that was used to power say a light bulb. Here is where the window comes into play. You get to use the mah that is available within the pack until you hit the cutoff voltage. That window is smaller for the higher amp draw applications. Where with the light bulb you will likely see the full 8000mah or maybe even more, the high amp draw application may only see 4000mah in that time frame. This is why running high mah, high C rated packs can be so beneficial as they will hold a higher voltage under load. Providing you with that larger window.

Hope this helps!

JoshMaxAmps -
Thanks for the explanation. I guess the voltage cutoff is set to a safe point based on the amp draw. High amp draw = quicker achievement of the first stage of 'notice' from the NAZA that I need to start paying attention - it just doesn't seem to correlate with the number of mah that I have used (put back into the battery).

The reason that I was thinking that a telemetry system can tell me status of my battery is by reading the mah used (read :fuel gauge). Maybe my thinking is mis-guided, but from looking at videos that are shot with the EzOSD, they seem to allow the pilot to see how much capacity of the battery has been used as way to monitor how much flight time is remaining.

Dale.

 

[Razzil]

Went to setup my new mini sd dvr today and the av connector onboard came completely off, so no EzOSD recording for me. Soldered it back on and still no go. Hopefully Foxtech will take it back.

I mount my 4S 6000mah between the skids as well.

 

[Ttelmah]

There are three calibrations on this in the Naza. The first one I changed was the one giving the actual voltage reading. This was reporting the pack voltage as being a lot lower than it really was, and since this is what everything else is based on, it was worth getting it better....
Only once I had this reading 'right', did I then adjust the set points.

Best Wishes

 

[RC Flying]

I prefer to use the lipo buzzers/beepers mentioned earlier because they measure the voltage in each cell and beep whenever one of the cells drops below whatever you set it to, say 3.7v or whatever. I feel safer using this as a measure than seeing how many mah I've used because sometimes a single cell can become faulty. You can also immediately see the voltage of each cell before and after. I do have an OSD as well that shows the mah used, but I wouldn't use it on its own. I've never really liked the DJI voltage monitor and don't really trust it to be accurate.

 

[rdalemercer]

I was able to get in the air today - finally. The wind was still a bit on the gusty side but I tried to find a quieter spot to test things out.

First things first. I changed the first level of protection to 13.7 (loss = 0) and the second level (Auto-land) to 13.0 (loss = o). NAZA assistant would not let me set the level lower than 13.0v.

Flight time was 7'20" - which is much better than the 90 seconds that I got last week. However, that was with a 5000mah battery strapped between the skids. I put 3100mah back into it so if my math is right I should be able to get ~9' flight (hover) time out of it when it finally gets sorted.

My flight was not without its challenges. I used the same NAZA settings from my F450 to start off and it needs to be refined as it moved around a lot even in GPS mode. I also have the GPS disc at a slight angle (tilted forward) on the top of the canopy which may be creating some of the issues. I've taken a spare piece of CF sheet tonight and made a GPS disc shelf that I will attach to the back body screw. Once I get that done, I'll make the necessary adjustments in the NAZA assistant and re-calibrate the GPS with the spin-dance squence.

I'd be happy to hear other CX4 pilots NAZA settings to see how they differ from mine.

I've ordered the IISI telemetry unit which should provide the accuracy that I'm looking for re: mah used. I hope it arrives before I leave on 4/2. My wife and I are taking a month long trip to the West coast via the Rockies across to Reno, down through Yosemite, around the south end of California and to the state parks in the 4 corners/ We've got to be home by 4/29. I'm hoping to get some great flying in along the way so I'm trying to get this flying right before I leave.

I chewed up a 9/5 prop today so I'll wait until my order gets in to fly it again. Until then it's back to the F450.

Thanks for all of the suggestions, discussion points, input and support. I really appreciate it!

 

[RC Flying]

Much better flight times, well done. I've always found it easier to get longer flight times with my smaller quads than my larger hexacopters, it just starts getting more complicates as things get bigger with more motors. I've been flying a TBS Discovery recently and still don't know how long it will fly for as I've always finished what I wanted to film/photograph before the low voltage warning comes on. Longest I've done is about 8 minutes I think, but usually flights are more like 6 or 7.

Anyway, I'm totally jealous of your month-long trip around California - that's totally on my to-do list.

 

[rdalemercer]

I was going to haul my CX4 apart soon and upgrade it to the v2 platform, so I can take some pictures of all the wiring of the EzOSD setup. Pictures are priceless in a similar setup sometimes.

Thanks Razzil.
I agree completly! Pictures do tell a priceless story sometimes when you're (me) stumped.

I'd aslo like to get a copy of your Assistant settings as those might help me understand how you've set up your CX-4.

I've sent you a PM.

Thank you!
Dale.

 

[Razzil]

Sorry for not getting back to you sooner, haven't been on here much the past few weeks.
If you're having issues with your EzOSD wiring, take some pictures and send them to me, replyed to PM with email address.
I'm about to order some parts for the V2 and mount the CX113 gimbal that I picked up awhile back, so I'll get some wiring then.
That being said, send me some pics of how you think you're going to make it work and I'll look them over and do up a PDF.

The Assistant software settings are pretty much 130 gains all around.
The mounting is dead on, note the hobbyking arm and motor mount out the back.
I hate the idea of having the GPS on that top mount and having to remove it when you want to open it up.
To tell you the truth, I think I'm getting better GPS results this way.

Here are some pics to help you out.

The landing gear is a combo of XAircraft parts and the Droidworx VM POV mount plate.
I wanted a quick release system so I could strap it to my kit-bag. The quick release wasn't available then.

View attachment 10545 View attachment 10546 View attachment 10547 View attachment 10548 View attachment 10549 View attachment 10550

 

[rdalemercer]

Hi Razzil,
Thanks for the photo's and information on your gain settings - and your email address. This is turning out to be a different handling quad than my F450 / Disco. I'll set the gains at 130 across the board and see if it helps things out. I'm still zeroing in on the proper setting for the CX113 for my RePlay XD. It's too sensitive (moves too much) so I obviously haven't found the right combination yet. There were no instructions for initial settings so it's been trial and error.

As you can see from the photo's, I've attached the GPS disc to the rear canopy mounting post. There was a poster on this forum that had a better looking one that I think came from droidworx, but I couldn't find it anywhere or get any information on it -- so I just mae my own out of thin carbon plate. The declination is set for my area of the world at West 5 degrees.

You can also see the PDB setup and the IISI Telemetry unit installed. I havn't flow with this yet as we've been seeing snow almost daily for the last few days. It's tough to go from 50's to snow and then back to the 50's by this weekend if the weather guys are correct. I plan on keeping the NAZA first level of battery protection set at 13.7 until I can fly the telemetry unit and see that it's doing things right. Once I trust it, I'll turn off the NAZA battery monitor.

Additional photo's are of the overall installation and the quick-release gear.

Re: the VTX and OSD mounting location: there seems to be quite a bit of real estate on the top plates (Front, Left and Right) + the rear plate where I have mounted the Receiver. I was trying not to cut holes into the canopy so I may just add the VTX to the rear mounting area and slot the bottom of the canopy to facilitate removal and installation. Any suggestions on what electronics to keep away from each other would be helpful too.

Thanks again!
Dale.
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[Razzil]

That HPRC 2700 case you have ... are you putting your Droidworx CX4 in there?
I figure we need a bigger case ... something on the lines of the Pelican 1650 or 1690.
One thing I hate doing is unscrewing the props for transporting.
This is what I've been doing up until now ...

View attachment 10635

 

[rdalemercer]

The CX-4 V2 has removable landing gear, so it fits in there with no problem. I remove the props and gear. Turn the gear upside slot the CX-4 booms under the skids (they come off too, but it's a bother to get them back on).

See the attached pics (sorry, left the props on) and I didn't add the second layer of foam - but you can get the idea.
View attachment 10636View attachment 10637

 

[rdalemercer]

I've also hollowed out the front area where the CX113 fits nicely without putting any pressure on it during transport.

 

[Razzil]

I found that taking the props off so often, worn down the threads and eventually had to be replaced.
I like that smaller case though.

 

[rdalemercer]

I checked out quite a few cases based on the size that I was looking for. Peli's were too high for what I wanted to spend (<-- this coming from a guy who just bought a CX-4!!)

Anyway, it seemed to be what I needed and I've been happy with the case after it arrived and I started to fit the CX-4 inside. I can remove the landing skids (rods) from the gear also and slide it sideways into the case, but how I have it configured seems to be the least amount of fuss. I also still have room to hollow out an area for some spare props, the battery charger and 4 or so 4s5000's.

 

[rdalemercer]

Today dawned sunny with a bit of wind at 5~10 mph .... a perfect day to try new things.

Gains were set at 130 across the board. 4s5000mAh (35C) fully charged hung underneath for balance. Graupner 9/5 props installed. IISI Telemetry unit installed and set to alarm at 25% (remaining) bettery level. CG: a bit nose-heavy (~30mm)

I recalibrated the GPS with the dance and synced with the satellites. Turned on the RePlay XD, spun up the props and --- lifted off into a hover ... and the CX4 turned left about 20 degrees. Checked the controls to make sure that I was in control and took off down the driveway and up the street (yes, slowly) around the end and back again and then off to the back yard ... still holding a bit of right rudder into the stick to keep it straight. Brought it back to the driveway at 8' and hovered until the IISI alarm went off at 25% - for a flight time of 9'23" (eCalc showed 10'20" at hover).

I charged the battery after the flight and put back 3804mAh into a 5000 mAh battery for 76.08% ... so the 25% battery alarm is working.

I feel pretty good about this since I started with a 90 second flight!

Only two issues remain:
1. setting up the CX113 gimbal - which is just more trial and error. The Automatic Control Gain is set at 25% with the Manual (tasked to the left side slider) is at 8.
2. I have some "Left" yaw that happens unexpectedly - in fact I almost have to hold some right rudder in order for it to fly straight. I'm not sure why this is (the GPS is set to 5 egree West declination for my area of the world) but its happening none the less. I can hear the props spin up as I feed right rudder into the control as if it's fighting my input. The trims in the TX are all set to "0" (including sub-trims).

Any ideas on #2?

 

[Razzil]

#2 - I have my GPS set around 15-13 degrees left-west. One thing I did notice is that the x,y,z settings need to be dead on. Slight differences in measurements make a difference. Adding or removing weight also a contributing factor. On my previous Hoverfly Pro board, it was a big issue, having to calibrate each time weight changed. DJI isn't so bad, but it does make a difference. Keep in mind that if you move your gains, that subtrims don't fool with the fail-safes it setup. Have you moved any wiring around lately? try re-calibrating with nothing magnetic near you.

#1 - I was thinking of opening a thread regarding that CX113 gimbal and users recommended pitch and roll settings they use with DJI Naza or Wookong. I had mine hooked up for an hour of tinkering awhile back but haven't used it since. Hopefully, soon I'll be able to get that setup and working and let you know I make out. There are a few users here with that CX113 gimbal, but they are slim to none. Maybe 10 that I know of.

What brand of 4S5000mah battery do you have?
I'm looking for a smaller one now for my TBS Discovery
Maybe 4S-4000 or 4S-5000 pending on measurements and weight.
MaxAmps seem to be lighter than others, have a higher C rating and measure smaller, expensive though.

 

[rdalemercer]

#2 The weight hasn't changed. I did notice when I checked it (just now) that the X axis was set to "0" and should be -11 Y and Z are correct. I'll fly again tomorrow and see if it still exhibits the same tendency to turn left without input. If you are in St John's, your setting in correct as is mine for central Kentucky. I don't think that declination is the issue as the F450 flies fine (straight) with the 5 degree West setting. It's probably the X axis being -11 off from what it actually is that's causing the issue.

#1 - I see your thread. I'll contribute as I dial this in.

I use two type (Brands) of batteries:
1. Hyperion (I doubt that I will purchase these again as the cost is too high compared to other brands)
a. 4S 35C 5000mAh. These were purchased with the F450 in mind and I do fly it with them getting ~14 minutes of flight time.
b. 4S 35C 2600mAh which I use for the F450 Flamewheel.
2. Zippy 4S 40C 5000 mAh <-- I purchased these specifically to fit inbetween the top and bottom plate of the Discovery. They will, of course, also fit under the gear rails of the CX4.
Note: on the Zippy's, you'll need to purchase a connector adapter for your setup (I use deans) as they come standard with a bullet connector.

 

[rdalemercer]

Bummer.
Until I saw the picture that you posted on the CX113 Gimbal thread - that's what I thought I had. It turns out that I have the "mini" -- just a single axis gimbal (half the price)....so it should be half the setup difficulty

....and the beat goes on.....

 

[rdalemercer]

Update:
I re-set the GPS and confirmed that it was setup correctly in the Assistant Software. When flying - in GPS mode - I am still having a slow left hand rotation when flying the CX4. I could not correct it with trimming the rudder channel. I thought that maybe it was the X axis not being setup correctly (prior = 0, now = -11).

I'm at a loss. Has anyone had any experience with correcting a slow left hand rotation? I have the GPS disc mounted as per the attached picture.
View attachment 10748View attachment 10749

Thanks -
Dale.

 

[Razzil]

Just for @#$ and giggles, position the GPS a little more to the left ... 15 degrees or more, I'd really like to hear the result.
Here's a pic of mine ...

View attachment 10750