Hi, I'm building X quad with 1000kv motors and 9443 props with APM 2.6. I want to fly with 2x 5000mah batteries but I'm getting only half of my motors power and quad is barely lifting itself.
I've checked ESC and Radio calibration and all seems to be ok. My throttle in radio calibration is 1060(low) and 1875(high).
RC3_DZ is 30
RC3_MAX is 1950 - but changing it down slows motors and up don't have any influence.
RC3_MIN is 1054
RC3_REV is 1 - Normal
RC3_TRIM 1060 - no influence on motors speed.
Additionally THR_ACCEL_D = 0, THR_ACCEL_I = 1,0368, THR_ACCEL_IMAX = 800,
THR_ACCEL_P = 0,5184, THR_ALT_P = 1,
THR_DZ = 100, THR_MAX = 1870, THR_MID = 500, THR_MIN = 150, THR_RATE_P = 5,
and TRIM_THROTTLE = 810.
Please give me some advice on getting it work in full range so throttle stick position is equal to motor spinning speed in %.
Replies
Artur, could you please tell us the weight of your quad, and the specific moor and prop you are using? I just want to do a quick double check to make sure your motor/prop system is specced strong enough to lift your vehicle.
Sure, motors are exactly EMAX MT2212 935KV and props will be Gemfan 9443 or 1045, i have 30A Emax ESC's and this config should have above 2400g thrust :)
Weight without batteries is 737g.
But with one battery or two (2x 465g) I would still like to have some control above 50% of my throttle stick :)
PS. This Quad with 9443 props has lifted two batteries in indoor test but without much reserve, i think this reserve I need is blocked by APM.
Artur,
Unfortunately, I think your copter is overweight. Your all up weight with two batteries is 1667 g. That is 69% of your 2400 g estimate. The rule of thumb is that your vehicle should weigh less than 50% of your max thrust, but less weight is always better (a better thrust to weight ratio will give you better maneuverability). APM does keep some "throttle" in reserve. It does this so that it can still maneuver. You may be able to decrease the amount that the APM withholds, but I do not know how. However even if you do this, I do not think your copter will be maneuverable enough to fly, and it will go completely bad when the battery gets low. Maybe try a more powerful motor/prop, or fly with only one battery. Good luck!
Thank you for your answer. I was aware that I,m trying to use more thrust than I probably should. The plan was to be able to fly with one or two batteries so i have a frame for both uses.
My main issue is that I was using CC3D in my previous build of 250 quad and there is no feeling of being limited in any way.
APM is more sophisticated but still should have a big red button "Push at your own risk!" allowing to change anything :) I think I'll look into firmware code.
Thanks again, regards :)