Hi All,
Before I fly my Xaircraft V8 frame with APM 2.5+ with 2.9.1-dev firmware (I compiled it), I have been checking motor output, etc. I noticed that measured at the APM output channels, at full throttle via a Futaba T8FG, the PPM going to the ESCs is 1.81 msec. Assuming a normal range of 900 - 2100 usec for 0% to 100% power respectively, 1.81 msec would translate into 76 % of full power.
I measured the PWM coming out of the radio receiver at full throttle at 1.94 msec. I am not sure of the translation between rc input and rc output, so i thought I would ask the experts. I spent enough money on crash repairs with the original XAircraft AP and want to avoid any more wrath from my wife ;-)
Are my readings normal for both max throttle PWM coming out of the receiver and going to the ESCs from the APM ?
Could anyone give me ballpark maximum throttle PWM values from the APM to the ESCs with a copter ? is 76 % maximum PWM width expected to in order to have wiggle room to manuever the copter ?
Thanks for any help.
Regards,
John Le Clair
Replies
The normal R/C PWM range is 1-2ms. So 1.94ms throttle is 97%. Those values can be over driven in some radios (hence the 900-2100 range in APM to make sure you catch the signal), but the standard values are still 1000-2000us.
On top of this, most ESC's without user calibration have a default operation range around 1100-1900us to make sure they work with all brands of radios.
So the only correct answer that works with all brand of radios and different setups, is that you must calibrate the ESC range to fit the radio/APM output.