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Old Mar 25, 2012, 07:45 PM
jesolins is offline
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Tri-Quad-Hexa-Octo-copters!!
United States, TX, San Antonio
Joined Feb 2007
15,136 Posts
Gents,

Here is KapteinKuk's ESC response thread with scope data: http://www.rcgroups.com/forums/showthread.php?t=1250488

Note that while Art's previously posted video of the ESC firmware comparison's of a very good figure of merit (FOM) operational test of how an ESC firmware affects motor/prop and a very fast gyro update, it would be excellent and more robust with some additional metrics: http://www.rcgroups.com/forums/showp...55&postcount=9

From the ESC recommendations and converting ESCs to I2c and to faster PWM section in the Quadrocopter and Tricopter Mega Link Index
--TIP 11: For faster ESC PWM update rates for use on most current flight controllers that output ~400Hz update rates, it is recommended to flash Quax/SimonK ESC firmware to take advantage of the higher performance. You can DIY per the Fast PWM links such as Nek's SimonK fast PWM firmware thread, or order the ESC's specifying that you want the fast PWM loaded from Ken in the USA at www.quadroufo.com , or Timecop in Japan at www.abusemark.com , or Dan in China at http://www.multircshop.com/site/inde...product_id=627., Flitelab in Canada: http://www.flitelab.com/OnlineStore/...hedSimonK.aspx
--Conversion thread: http://www.rcgroups.com/forums/showthread.php?t=766589


While some ESCs such as the Turnigy Plush's will give the multicopter the appearance of flight stability, the Simonk firmware still is the best out there compared to OEM ESC firmware ESCs that are not designed specifically for multicopter use and includes what I seek in ESC performance for multicopters:

FWIW Here is my wish list for proper Multicopter ESCs:
Multicopter ESC requirements:
- The PWM ESCs should be able to do at least 400hz + update rate and running at 16khz.
- ESC endpoint throttle calibration must be manual. Automatic calibration is bad for multicopters.
--Note: This must also consider that there are some different throttle ranges, i.e. 200-1200μs vs. the more standard 1000-2000μsaccomadate the various throttle ranges
- Linear throttle-no curve or "smoothing".
- >250+ steps.
- No LVC or the ability to turn it off.
- ESC prop stop if stalled by hand, etc, then restart.
- Governor off.
- Brake off.
- Start normal.
- Motor timing optimization for 12+ pole outrunners 500-1500Kv. (Dynamic changes are bad for multicopter performance).
- Available in Amp ranges from 5-80A. Typically 20A, 30A, 40A.
- Graceful over current protection that does not constantly affect multicopter performance as it fights windy conditions.
- No BEC on-board.
- Also some I2c versions or the ability to do both PWM and I2c like the YGE ESCs can do.
- Future considerations:
--Two way communication for dynamic braking with inputs from a flight controller.
-- Serial comm.
Cheers,
Jim
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