User manual

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Appendix
Customize Motor Mixer
For a multi rotor, the roll, pitch, yaw and vertical axes are contributed by the combination of rotors’ outputs. This procedure is called Mix
Control. The proportion of rotors’ outputs is decided by the mechanical structure. Customers can setup the motor output coefficients C
in [Motor Mixer]  [Customize] so as to realize the Mix Control.
 Before customization, you should have the important knowledge following:
1. Motor output = C × Stick position (A or E or T or R).
Torque produced by motor = Motor output × Force arm of motor (L) = C × Stick position (A or E or T or R) × L
2. The range of C is from -100% to 100%. Maximum C in the same column is 100%. The bigger absolute value of C, The
great effect of stick position on motor output. Stick position will not affect motor output when C is 0, which means the
motor output is fixed.
3. Each motor has four different output coefficients: C
T
, C
Y
, C
P
, C
R
. E.g. C
Y2
represents coefficient of M2 in yaw control; C
R5
represents coefficient of M5 in roll control.
4. Motor output is relative to its rotation speed. The bigger output, the faster rotation speed. Negative output does not represent
counter rotation, but slower rotation speed. Motor is still spinning if its output is 0.
5. Throttle stick position (T): Pull stick T<0, multi-rotor moves down; Push stuck T>0 multi-rotor moves up;
Rudder stick position (R): Stick left R<0, multi-rotor nose left; Stick right R>0, multi-rotor nose right;
Elevator stick position (E): Pull stick E<0 multi-rotor moves backward; Push stuck E>0, multi-rotor moves forward;
Aileron stick position (A): Stick left A<0, multi-rotor moves left; Stick right A>0, multi-rotor moves right.
6. Multi-rotor should keep balance along all the other axes when moves along one axis:
 To keep throttle direction balance, sum of all motors’ output should be 0 when apply rudder or pitch or roll stick
command;
 To keep yaw direction balance, sum of counter clockwise motors’ output should be equal to sum of clockwise
motors’ output when apply throttle or pitch or roll stick command;
 To keep pitch direction balance, total torques produced by motors at each side of pitch axis should be the same
when apply throttle or rudder or roll stick command;
 To keep roll direction balance, total torques produced by motors at each side of roll axis should be the same when
apply throttle or rudder or pitch stick command。
7. To pitch or roll control, proportion of coefficients of the motors at the same side of pitch or roll axis should be equal to the
proportion of force arms of those motors: C
m
/C
n
= L
m
/L
n
; Coefficient is 0% if the force arm of that motor is 0.
Hex-rotor V
M1M2
M3
M4 M5
M6
Front
M1M2
M3
M4 M5
M6
Roll Axis
Pitch Axis
Yaw Axis
d
2d
a
a
Now we take the Hex-rotor V as an illustration to introduce how to customize motor mixer.
 Throttle
Usually, we want push the throttle stick to ascend the multi-rotor; pull the throttle stick to descend the multi-rotor; put the throttle stick at
center point to hover the multi-rotor. We also want multi-rotor to keep balance along all the other axes when apply the throttle stick
command: