INAV Cleanflight two Quadcopter FORMATION FLIGHT (TEST1)

cleanflight inav(1.1 modify) Formation flight (test1)
Showing ATUO TAKEOFF + AUTO LANDING + Flying around by transmitter sticks.
tow quadcopter formation flight with RC-input not MSP(Multiwii Serial Protocol) .
(sonar+baro version)
used sonar to adjusting baro altitude, between 2cm~2.00m.
hardware: mega2560,promini 328 + nRF2401 module+OTG cable+cell phone
software: android studio +[UsbSerial for android]+ arduino+[RF24 class for arduino] + MSP (Multiwii Serial Protocol)
inav :ANGLE+MAG+NAV POSHLOD+NAV ALTHOLD+GCS NAV+MSP
2212/980kv
10x45
11.1v/3S/2200mAh
M8N + H5883L (external)
FC:SRP_F3 (10 DOF)
SONAR HC-SR04
LED WS2812B
F450
ESC 20A,all N-FET, BLHELI 14.4 ,Damped light
Radio:AT9 + RD9(10CH.)
INAV Setup:
default PID
oneshot on
looptime = 1000
set nav_use_midrc_for_althold = OFF
set nav_extra_arming_safety = OFF
set nav_user_control_mode = CRUISE
set nav_mc_hover_thr = 1360
set alt_hold_deadband = 70