BLHeli - Double brushless for mCP X - with governor coming

[Roffey]

Originally Posted by sskaug

Great! Just let me know if I can help.

Steffen

All looking good Steffen. I still have yet to try your flash, but that's in the list Couple of questions while I think about it, if I may.
What resolution did you end up with when you are measure the tail pulse? (uS)
Is the tail rock solid on fast sideways flight? Particularly right side? I only get really solid with the 5gm so far.

Thanks

Dave

[sskaug]

I used a 1us resolution for the tail (max at 125us). And a sample rate of 1ms. It may seem that 1us resolution is low, but the fact that it is measured every ms and presumably with some noise will make the effective resolution higher (by averaging some noisy measurements).

Yesterday I tried left curve tail down funnels and the tail holds perfectly. This is where the tail motor runs fast. In the other direction, there may be some limitations by the minimum run speed of the tail motor (to avoid it stopping). We'll have to test it.

As for reprogramming for sale, I am not going to do that. And also the software is bound by Bernard Konze's (and now also mine) terms of non-profit. However helping friends at self cost is a great thing. Check out fjoe's plans in this thread: https://www.helifreak.com/showthread...80#post3438980

Thanks,
Steffen

[Roffey]

Originally Posted by sskaug

I used a 1us resolution for the tail (max at 125us). And a sample rate of 1ms. It may seem that 1us resolution is low, but the fact that it is measured every ms and presumably with some noise will make the effective resolution higher (by averaging some noisy measurements).

Thanks Steffan, just checking. In the early flash I did, I used higher res, and I wanted higher pwm motor rate, and with all else, I think there was too little understanding on my part. (Still is!
I do use 2000 res at a much higher rate on my converter, to get the curves I want to play with, but that's probably overkill!

Glad you got there and thanks for sharing your work.

Dave

[sskaug]

Yesterday I flew with the Walkera versions of the BLHeli ESCs, and they worked great. Not sure there is much difference from the Feigao version though. But at least in theory the Walkera versions are better (lower mosfet resistances, more accurate clock frequency, and regulated supply for the MCU).

Also I did increase the integral part of the governor gain a bit, mostly in order for it to cover a wider pwm range. Not a very noticable difference here either. Ideally I guess the software should be rewritten for a 24bit integral.

Attached is rev 1.2.BLHeli Rev1.2.zip

[distructor]

Thanks to everyone for all your contributions and for sharing. Ordered the WOW-07, Walkera Brushless 2g Tail Motor, FEIGAO-6Ax2 + DMC2020USD-13x30 and AVRISP2. Looking forward to getting started. Will keep you posted on my progress.

I'm assuming the PWM pickoff is the same as in the early BL tail threads, however on earlier threads, the other connections (trimming?) on the 3-1 beard looked a bit confusing. Has the ESC firmware updates taken over those modifications? If not, is there a summary of those modifications as they stand today?

Thanks,
Norm

[sskaug]

Originally Posted by distructor

Thanks to everyone for all your contributions and for sharing. Ordered the WOW-07, Walkera Brushless 2g Tail Motor, FEIGAO-6Ax2 + DMC2020USD-13x30 and AVRISP2. Looking forward to getting started. Will keep you posted on my progress.

I'm assuming the PWM pickoff is the same as in the early BL tail threads, however on earlier threads, the other connections (trimming?) on the 3-1 beard looked a bit confusing. Has the ESC firmware updates taken over those modifications? If not, is there a summary of those modifications as they stand today?

Thanks,
Norm

Great. Look forward to hearing your results!
The pickup points are on the resistors of the 3in1, on the points marked "main" and "tail" in Roffeys post: http://www.rcgroups.com/forums/showp...postcount=1096

The ESC code uses 8kHz positive PWM as input. This is what the chip on the 3in1 delivers and there is no need for a converter. Good luck!

Also a note on the tail motor. Will be interesting to see your results on this 2gm Walkera. I have not tried it, possibly a 2gm motor is a bit weak, and you may have to tweak the startup parameters. In my heli I have about 30gm of thrust from the tail and currently use this motor that works great: http://www.hobbyking.com/hobbyking/s...x_GPS_C03.html

-S

[Dylwad]

I was going to ask what tail motors you were using, I'm looking at the HP02T and HP03T, Which would you suggest of the two? http://www.chinesejade.com/walkera43BLMotorEsc.htm

The C03 looks to be around 9000KV, what prop are you using on it?

[rellik5397]

Originally Posted by Dylwad

I was going to ask what tail motors you were using, I'm looking at the HP02T and HP03T, Which would you suggest of the two? http://www.chinesejade.com/walkera43BLMotorEsc.htm

The C03 looks to be around 9000KV, what prop are you using on it?

I got the tail motor from this link with the mcp I bought. It's one of the two under the 10A esc, it's one of the two crom ones, are these any good to use as a BL tail?

[Bisso]

Originally Posted by sskaug

The pickup points are on the resistors of the 3in1, on the points marked "main" and "tail" in Roffeys post: http://www.rcgroups.com/forums/showp...postcount=1096

I'm a bit confused on this one, did anyone manage to get something out of the 4 "debug pads" on the front of the mcpx board?
Seems like an easier place to solder

[sskaug]

Originally Posted by Dylwad

I was going to ask what tail motors you were using, I'm looking at the HP02T and HP03T, Which would you suggest of the two? http://www.chinesejade.com/walkera43BLMotorEsc.htm

The C03 looks to be around 9000KV, what prop are you using on it?

I have not tested the 2g in the heli yet, but fear that it may be too weak. The 2.9g should be good, but also remains to be tested. On the C03 I use a cut down SR120 prop. From some measurements I did a while ago, it seemed like the thrust of the C03 was about constant versus (SR120) prop diameter, but efficiency increased a lot when cutting it down. The dynamic performance of the tail will probably also be affected. There is room for a lot of investigations!

As for the "chrome" motors of Chinese Jade, these should be similar to the 2g motors mentioned previously. Roffey has been using them, I have not yet.

-S

[fjoe]

Originally Posted by Bisso

I'm a bit confused on this one, did anyone manage to get something out of the 4 "debug pads" on the front of the mcpx board?
Seems like an easier place to solder

I did look at this but could not correlate tail commands with any of the 16bit "debug" signals out of that port. It seemed to me that these are only for the FBL system, but this needs to be confirmed.

The easiest way to look at that port is with one of the FTDI USB serial cables the 3.3v version.

http://www.ftdichip.com/Products/Cab...BTTLSerial.htm

Your looking for the TTL-232R-3V3 model.

I'll try and put together a post on my finding this week...

[Mbrun]

I finally got time to fix the gear meshing and solder up the last bits. It flies!!! Tail is steady at 65% throttle up to 80%. I only flew it in my livingroom and did some pitch pumps to get a feel for it. I like it! I'll try to post a video next time we go to Lommedalshallen.

[amb1]

Love to see this bl tail doing some Hard flying, please post. Wish I was in Norway, beautiful part of the world...

[Dylwad]

Received my Feigao ESC's today from Graves RC, they do not have the Atmel mcu's, they have Silicon labs F334's and looks like they are Hobywing clones.....

So the Walkera 10 amp ESC's are locked and you have to replace the MCU correct?

Dylan

[sskaug]

That was a pity! I ordered from wow a few weeks ago, and they were Atmel. I believe these from HC will work very identical to the Feigao, the only difference is that the programming interface will have to be soldered directly to the MCU. Which is not really that hard.
http://www.hobbyking.com/hobbyking/s...dProduct=10573

The Walkera MCUs are locked, serial programming is disabled. Parallel programming may be possible, fjoe is exploring that: https://www.helifreak.com/showthread.php?t=360116
I have replaced the MCUs with 88P or 88PA. It works, but it takes some soldering.

[fjoe]

Originally Posted by Dylwad

Received my Feigao ESC's today from Graves RC, they do not have the Atmel mcu's, they have Silicon labs F334's and looks like they are Hobywing clones.....

So the Walkera 10 amp ESC's are locked and you have to replace the MCU correct?

Dylan

The one I got from WOW a few weeks ago was an ATmega. I need to order another one. What did the packaging look like?

[distructor]

Originally Posted by fjoe

The one I got from WOW a few weeks ago was an ATmega. I need to order another one. What did the packaging look like?

Ordered 3 from WOW last week... all ATmega8L.

[Dylwad]

Here's the packaging. Now I wonder if I got an old version, or new?

[Dylwad]

Also the PWM on the V2 board is much lower, I cant measure for sure but it sounds like 2Khz. The tail is much improved on it, and there's no drift accumulation, just better overall! How hard is it to change the code for the lower frequency?

[sskaug]

The lower pwm frequency should be a very easy code change. I have two v2 boards ordered, and I will publish updated code for v2 when I have had the boards a few days.