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Old 07-24-2016, 07:50 AM   #41
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Well, you Figure of Merit without the payload, assuming 6S voltage, is 38%. This is pretty reasonable, and compares to 37% for me. Meaning essentially, the two system efficiencies are exactly the same and the only reason you're using so little power is because your disk loading is so low.

You have 1.70kg/m2, mine is 4.4kg/m2. With the 30lb payload, your disk loading jumps to 5.36 kg/m2.

However, with the payload, at 38A and 24V, your figure of merit is 99.6%. Which is basically impossible. You've nearly created a perpetual motion machine. So, something seems wrong here.
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Old 07-24-2016, 08:46 AM   #42
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I can only show the mechanical and electrical setups, along with logs.
I laid out and assembled what I saw as a reasonable combination of components.
A perpetual motion machine, everyone knows that is not the case.
The bird has an innate tendency to lift off during spool up long before it reaches the operating HS.
My guess is somewhere around 300 - 500 rpm.
Exactly, how do you calculate the figure of merit? and what component variables are you plugging in?
Side note/question:
What blades are you using?
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Old 07-24-2016, 09:54 AM   #43
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https://www.google.ca/webhp?sourceid...copter%20rotor

1000mm blades, 38 Amps, 24V, 14lb + 30lb

Full-scale helicopters, with millions of dollars spend on optimization, typically achieve 60-70% FOM. And keep in mind, that is based on shaft horsepower.

In our case, we don't have shaft horsepower, I'm calculating based on electrical input power. So, it all gets even more implausible if you were to actually account for the electrical inefficiencies.
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Old 07-24-2016, 10:30 AM   #44
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I have to assume that your using (at least on the 800 ) symmetrical blades on your machines.
That is not the case with mine ...

You get a whole lotta lift for a lot less power.
That has to figure into your calculations, or at the very least the difference between the two.



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Old 07-24-2016, 10:54 AM   #45
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No, it doesn't matter. FM is how close you get to the theoretically 100% perfect efficiency. So there is something wrong, because what you are suggesting is impossible. It doesn't even account for the power required to run the tail rotor.
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Old 07-24-2016, 11:40 AM   #46
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I'm not suggestion anything, just putting out thoughts.
Well, what ever the cause and/or effect it is, it's been that way for years.
Never thought much about questioning it.
I do agree that it is not 100% efficient, and never claimed it to be.
But it works, and I'm satisfied with the results.

You might take some solace in the fact that there well may be errors in the data log.
Wouldn't be a big surprise to me that when you run at either extreme of the operational window of these hobby grade components, accuracy comes into question.
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Old 07-24-2016, 12:20 PM   #47
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It's not just a small error. It's totally implausible. If the 30lb payload test was done at 12S instead, then it would be able 50% FoM, which is still amazing, but at least plausible.

The equations are easy. If you're an engineer, should be easy to check.
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Old 07-24-2016, 12:55 PM   #48
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All I can say:
Castles ESC's, if driven at less that 50% throttle are going to go thermal.
Can we agree on that?

Considering the durations and running temps are @ or below 120*F ( 48.9C ) @ 800RPM
It's fairly reasonable to conclude the ESC is operating at or really close to 100% output.
Can we agree on that point?

I'm not trying to convince you of anything or change your mind, nor am I arguing your thoughts.
I agree it can not be 100% efficient.
I can also see and accept the probabilities of inaccuracies of the data log.
There is only so much one can do to control the accuracy of the data.
I did this starting over 5 years ago.
All I did was present the numbers.

Beyond that, there is not much I can do.
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Old 07-27-2016, 12:15 PM   #49
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I might mess you guys up. I have a phoenix ice 2 120 that I soldered the motor two. No bullets. The bearings needed to be replaced so I swappes out another 700mx motor with a edge 120. Everything the same I was showing 50 amp averages on the edge. On the phoenix normally 30 amp averages. Castle wouldn't be a good choice for endurance and low throttle output.........but what in the world with the difference in current draw. I haven't de soldered and used the exact same motor but still.


Here is some recent video. 60mph on a few of those. At 30lbs I need the higher headspeed. The asyms were bad in the wind. At some point I need to put bullets on and swap motors and see if there is something actually different between Pheonix and Edge ESCs.

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Old 07-27-2016, 12:50 PM   #50
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Interesting...
I've personally never found any comparative information.

I would be very curious to see different versions / revisions and sizes of the ESC (ICE2/ EDGE) attached to the same motor and see if there is a difference.

Wouldn't that be a trip, if by some fluke a mating of a specific variant of ESC to a specific revision software and motor yields some optimum setup
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Old 07-28-2016, 08:48 AM   #51
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I highly doubt that's possible. 1000W is a lot of energy that would have to go somewhere. That's a space heater. More likely an indication of crap data coming from Castle.

All my data was collected by a calibrated current sensor directly on the wires.

Mapoff, your video looks great. Which gimbal are you using?
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Old 07-28-2016, 09:53 AM   #52
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A consideration that could be explored...
But crap data or not coming from Castle.
If your satisfied with your results
As I am satisfied with mine.

I care to think as one of my college professors at the time mentioned:
"Teachings and text books only get you so far, furthering knowledge is solely dependent on yet to be discovered possibilities."
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Old 07-28-2016, 10:25 PM   #53
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Rob, I think the data is correct because the telemtry I use shows voltage and it's always been a good indicator. I got from 50v to 43v typically and with the Edge I maybe get 8 minutes. With the Phoenix Im getting 12 minutes with the same batteries. Soon I'm going to put some bullets on there.

I wanted to bring that up because I can see where the ESC even if near the same model could be a huge factor in current draw. Now on my 700 3d CHP frame it's about 7-8minutes with 4000mah batteries at an average of 20amps. So the motor and ESC combo that was pulling 50 average on the camera ship only pulls 20 on a 10lb stunt bird, hovering and laid back flying.

The gimbal is a cheap chinese brushless that I eventually swapped the motors and cages out. I'm using the WASP. Was made in the usa and $100 cheaper. Made of aluminum too and holds 8017 motors. Then an Alexmos 32bit controller. I'm using the Blackmagic Production camera with 24mm and recently a 50mm lens. The whole thing looks like a science project but works. Have to use HDSDI->HDMI, HDMI->Analog, then Analog to VTX. Also am using dual IMU and dual tilt motors, so it's wires everywhere.
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Old 07-28-2016, 10:27 PM   #54
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Here is a poor shot of it. Not allowed to show what we were shooting yet so I got a teaser pic.
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Old 07-28-2016, 10:29 PM   #55
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Different shot. Roads blocked and everything.
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Old 08-03-2016, 09:07 AM   #56
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The motor that you changed, exactly the same KV? Same gearing? Something changed. There's no way that 1000W was just going up as heat somewhere.
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Old 08-03-2016, 10:12 PM   #57
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I agree. The motor that's the spare 700mx is around 516kv, but I also tried an Xera 470 which should have been even more efficient.

Like I said 112/10t and I hard wired my 470kv 700mx to my Phoenix. That pair came out while I redid the bearings. In the mean time I took the Edge and 516kv 700mx with the same gearing and rig. Then I kept the Edge and tried the 470 Xera (5025?). Both motors with the Edge was stupid high current.

I'm in the middle of the season but this winter when Im not lazy I'll put bullets back on with the Phoenix and I can do real comparisons.
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Old 08-13-2016, 07:47 AM   #58
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Default Re: Mapoff edge vs ice....

Mapoff:, so glad i saw this post, so i have an edge 120 on a heli, that now i can outfly and shut down almost at will. :/ So now its time for a 160 or 200 amp esc. The relavence is that i was going to take the edge and put it on my 800mm camera ship to replace the ice120 thats on it.
Now im wondering if thats a good idea? Id love to see some data, and am almost tempted to just go ahead and do a comparison and log temps, watts, current etc of each and see where it all lands.. im running a 440kv motor on my camera ship with an AUW of 18.96 lbs-24.6lbs depending on camera, lens, battery and atamos recorder selection.
Stating the obvious, if there is something to all this based on your observations id be worse off with the edge as id lose efficiency.
The only reason i care to swap out with the ice is for the white wire and the fact the edge is under a year old.
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Old 08-15-2016, 06:12 PM   #59
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You are in a better spot it sounds like to compare the difference. Maybe just a simple hover for a minute to see if the ESC's are different. I really want to know.
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Old 08-15-2016, 09:13 PM   #60
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Here is more footage from a new show coming out on Velocity called Toymakerz. Everything is real time. I haven't done any editing at all. No color correction, no stabilization. Its all cut edits because I'm still figuring out placement and there is two more days of shooting coming up. I'm hoping to get some more behind the scenes. A few of those clips were at minimum 60mph. It doesn't look like it but I was sweating and shaking. I used Atti mode so I could get the speed, but still focus more on camera placement. GPS only gets to maybe 45mph. More like 40mph. Full manual is just not worth it in a setup where you want to focus on smooth movements.

There is one on the highway where we passed the car. He didn't slow down. We were already pacing 60 before that, so it had to be 70mph, flying backwards.

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