Feb 06, 2013, 10:12 AM DJI Supporter Swanton, OH Joined Jul 2007 5,130 Posts You guys might consider just mounting the ClikIt somehow to Phantom. Guaranteed to rid you of Jello issues. https://www.rcgroups.com/forums/show...06&postcount=1
Feb 06, 2013, 10:16 AM
Suspended Account
United States, CO, Parker
Joined Jan 2013
3,566 Posts
Quote:
 Originally Posted by T J Gilbert HighGainTuning, since you're training technicians for a living, pick up the ball here and give us a lesson... "What do you want to know?" I thought it was obvious, but I'll be more specific. (And I apologize to you guys that prefer we keep technical conversations elsewhere...) With 3S: avg. max current (I saw) on video: 7.19 amps captured max current: 8.48 amps snap current: 21.16 amps (captured) With 4S: avg. max current (I saw) on video: 10.32 amps captured max current: 13.6 amps snap current: 31.84 amps (captured) I expected the current draw to decrease with a voltage increase because theoretically the same amount of power was required to spin the prop. The 4S currents were all higher than the 3S currents. What I'd like to know is your opinion as to why this occurred...
When I got to work today I put your question up on the screen for the class to read. Since they are 2 days from finishing this class and we just talked about this I had the students write me their response. Everyone did very well and I will sum it up.

If the resistance stays the same and the voltage is increased the current flow will increase. You could hear the results of that in the video. I often relate electron flow to water in class. If you increase the pressure (voltage) and you do not change the size of the hose (conductor) or spray nozzle (motor) that the water (current) flows through, you will flow more water (current). It is the same in an electrical circuit.

One thing I didn't point out but you may have assumed is I ran only 1 motor so the battery was dedicated to just a single device. With 4 motors in parallel to the battery there will be a greater voltage drop causing a lower current flow then you saw in the video so the video current flows were most definetely at their maximum. When flying with 3S batteries my hover is achieved at mid stick. With 4S batteries the exact same prop speed and hover is achieved with the throttle stick just below center.

I am mainly looking for longer flight times when the GoPro is mounted but the extra acceleration in manual mode for sport flying is a blast. If I have an ESC fail I will post that but I do not expect that to occur as I will also be attaching a heatsink to the MOSFET array.

Another place to gain flight time would be to disconnect the outer most LED. Each set of 3 are in series and disconnecting the outer will shut all 3 down. They apear to be 3 watt CREE LED's so there's 36 watts of savings if you don't need them.

I totally understand that electronics isn't everyone's bag and I am by no means trying to push the use of 4S batteries. Based on what I tested, I have no fear in using 4S batteries to extend flying time on the Phantom.
Last edited by HGT; Feb 06, 2013 at 10:47 AM.
 Feb 06, 2013, 10:54 AM Empire Support United States, MS, Ridgeland Joined Feb 2009 7,808 Posts @HighGainTuning Good answers for the newbies! (And for old farts too!) I was wondering if you were going to introduce e=iR.... And I wasn't trying to trick you. I was trying to ask you what a newcomer would say... I've seen pilots who were maxing out their ESCs think that they could go to higher voltages, enjoy higher RPMs, and not have to size up their ESC. The uninitiated might have benefited from a tach on the prop... I still think the currents you've measured are within acceptable ranges. And it's neat that you were able to use our tinkerings in your class. Way to go! Last edited by T J Gilbert; Feb 06, 2013 at 11:10 AM.
Feb 06, 2013, 10:58 AM
Videographer/Product Reviews
United States, WA, Spokane
Joined Oct 2012
1,864 Posts
Quote:
 Originally Posted by flitelab Took some captures from the video. Looking at it I would guess it is Sorbothane just based on how it looks and how it is cut a bit jagged as Sorbothane is very hard to cut smoothly. I have some here, I'll see if I can try attaching it with double sided tape. I need to test my current mount first where I use rubber grommets and Align Gel to isolate the screws/frame.
Question becomes whether this mount is a DJI product, or a third party's.

The video from the Phantom's view is quite good -- probably the best I've seen, and there is high production value in the overall presentation.

Is DJI thinking of introducing its own dampening system - I'd certainly like to know.
Feb 06, 2013, 11:00 AM
Joined Feb 2010
9,056 Posts
Quote:
 Originally Posted by daskim Question becomes whether this mount is a DJI product, or a third party's. The video from the Phantom's view is quite good -- probably the best I've seen, and there is high production value in the overall presentation. Is DJI thinking of introducing its own dampening system - I'd certainly like to know.
I would say no as it looks little more than a piece of sorobothane glued on. if it were production quality I would suspect it would be more uniform in shape. This to me looks like a quick DIY fix they did while shooting. In some scenes it has the normal mount.

I suspect that video has a lot of post production done so hard to really say how stable the raw video is.
 Feb 06, 2013, 11:05 AM Registered User Joined Jan 2013 434 Posts Here is the raw video shot at 2.7k. Its a test with sorbothane and a mount I've been playing around with. I crashed half way through the flight and this is the second half with unbalance, freshly crashed blades. I think the results are pretty good for that! I won't have a prop balanced until Friday so I'll have plenty of time testing just the mounts isolated ability. Lighting sucks right now but you get the idea.
Feb 06, 2013, 11:14 AM
Suspended Account
United States, CO, Parker
Joined Jan 2013
3,566 Posts
Quote:
 Originally Posted by T J Gilbert Good answers for the newbies! (And for old farts too!) I was wondering if you were going to introduce e=iR.... The uninitiated might have benefited from a tach on the prop... I still think the currents you've measured are within acceptable ranges. And it's neat that you were able to use our tinkerings in your class. Way to go!
Yeah, I'm not sure many here understand Ohm laws and Kirchoff's theories which is also why I did the video showing only a digital readout ammeter. I have the scope hooked up in the background with an inductive clamp if you really want to open up a can of worms. It shows every current pulse including the warning beeps.

I have a photo tach I could use if that interests anyone.

Yeah... the class just went through FET's, MOSFETS, SCR's, NPN and PNP transistors yesterday so that had better be able to answer your question.
Feb 06, 2013, 11:23 AM
Registered User
United Kingdom, England, Cambridge
Joined Jan 2013
10 Posts
Quote:
 Originally Posted by FITandFUEL Here is the raw video shot at 2.7k. Its a test with sorbothane and a mount I've been playing around with. I crashed half way through the flight and this is the second half with unbalance, freshly crashed blades. I think the results are pretty good for that! I won't have a prop balanced until Friday so I'll have plenty of time testing just the mounts isolated ability. Lighting sucks right now but you get the idea. http://www.youtube.com/watch?v=-eKSZ...ature=youtu.be
Looking good!
 Feb 06, 2013, 11:33 AM DR , EVIL Canada, QC, Montreal Joined Apr 2012 979 Posts Anyone know if parts are finally available,?
Feb 06, 2013, 11:35 AM
Registered User
United States, CO, Denver
Joined Dec 2002
947 Posts
Quote:
 Originally Posted by FITandFUEL Here is the raw video shot at 2.7k. Its a test with sorbothane and a mount I've been playing around with. I crashed half way through the flight and this is the second half with unbalance, freshly crashed blades. I think the results are pretty good for that! I won't have a prop balanced until Friday so I'll have plenty of time testing just the mounts isolated ability. Lighting sucks right now but you get the idea. http://www.youtube.com/watch?v=-eKSZ...ature=youtu.be
This looks good but I am only able to watch in 1080P max. Is the original available?
Feb 06, 2013, 11:42 AM
I never finish anyth
United States, TX, Houston
Joined Jan 2012
2,584 Posts
Quote:
 Originally Posted by R Hudson This looks good but I am only able to watch in 1080P max. Is the original available?
youtube doesnt support higher than 1080p
Feb 06, 2013, 11:45 AM
DJI Supporter
Swanton, OH
Joined Jul 2007
5,130 Posts
Quote:
 Originally Posted by MCrites youtube doesnt support higher than 1080p
It actually does, on some videos you'll see an option called "Original" which will offer resolutions higher than 1080p.

For example:
 NFS Shift Gameplay 2560 x 1600 video test (1 min 11 sec)
 Feb 06, 2013, 11:49 AM I never finish anyth United States, TX, Houston Joined Jan 2012 2,584 Posts Interesting... I still don't see that option. Maybe its a firefox issue. Good to see YT stepping up to higher quality.
Feb 06, 2013, 12:04 PM
Registered User
United States, CO, Denver
Joined Dec 2002
947 Posts
Quote:
 Originally Posted by MCrites Interesting... I still don't see that option. Maybe its a firefox issue. Good to see YT stepping up to higher quality.
I didn't even know until more recently myself. Tony (TonyTypeS) posted a 2.7K vid of the Phantom in this thread (I don't remember which page) in which the "original" was available in the "change quality" icon on the bottom of the viewing screen.

Side note: Ditch Firefox and move to Chrome. Life is good with Chrome
 Feb 06, 2013, 12:06 PM I never finish anyth United States, TX, Houston Joined Jan 2012 2,584 Posts Chrome and firefox are like boxers versus briefs... just a personal preference thing. IE on the other hand is a thong made of barbed wire.