Chapter 3: Channel Configuration, Servo Setup and Checks, and ESC Calibration

Output Settings

Channel Configuration

Open the Output page in AGC to configure each flight controller channel. AP firmware uses the multirotor Y-3 motor definition: the front-left motor is MOTOR2, the front-right motor is MOTOR1, and the rear motor is MOTOR4, as shown below. The rotation directions shown do not need to be followed, but the outputs must never be configured as MOTO1\MOTOR2\MOTOR3.

The following Assassin T1 example uses the wiring arrangement currently connected to the flight controller.

The flight controller has an integrated BEC. If an ESC also has a BEC, remove the center power wire from its connector and insulate it securely to prevent movement during flight from bringing it into contact with a conductor and causing a short circuit. Select the following channels for the aircraft control surfaces and throttle according to the wiring.

Servo and Control-Surface Checks

Tilt-Servo Check

In VTOL stabilized mode, both tilt servos should be positioned vertically at 90°, as shown below.

The ground station Output page below shows that in VTOL stabilized mode, the left tilt servo PWM value is at its low endpoint and the right tilt servo PWM value is at its high endpoint.

Adjust this according to the actual installation. The left tilt servo PWM value is not necessarily at the low endpoint on every aircraft in multirotor mode.

If one servo is vertical at 90° while the other is horizontal at 180°, enable Reverse on the channel for the incorrectly positioned servo. If both tilt servos are raised but not fully vertical, adjust the channel 7 min value and channel 8 max value until both are vertical.

Example: If one servo is vertical at 90° while the other is horizontal at 180°, enable Reverse on the channel for the incorrectly positioned servo. If both tilt servos are raised but not fully vertical, adjust the channel 7 min value and channel 8 max value until both are vertical.

If the left tilt servo is not vertical and its angle is less than 90°

Example:

If the left tilt servo is not vertical and its angle is less than 90°

In fixed-wing stabilized mode, both tilt servos should be horizontal at 180°, as shown below.

The upper-right area of the ground station shows that in stabilized mode, the left tilt servo PWM value is at its high endpoint and the right tilt servo PWM value is at its low endpoint. The adjustment method is the same as for correcting nonvertical tilt servos in VTOL stabilized mode. In FBWA mode, adjust the channel 7 maximum for the left tilt servo and the channel 8 minimum for the right tilt servo.

Example:

If the left tilt servo angle is less than 180° Increase the channel 7 max value. Conversely, if the left tilt servo angle is greater than 180°, decrease the channel 7 max value.

Similarly, if the right tilt servo is not correctly aligned, adjust the channel 8 min value.

In summary, servo position and angle can be controlled precisely by adjusting the PWM minimum and maximum values for each mode. These endpoints can be adjusted and optimized directly on the MP ground station Output page.

When adjusting min and max values, the ground station may display an out-of-range warning. Click Confirm to continue.

5.2.2 Fixed-Wing Control-Surface Check

(1) Use the radio transmitter to switch to stabilized mode and check the control surfaces. Apply pitch, roll, and yaw inputs and verify that the aircraft control surfaces respond correctly. If a surface moves in the wrong direction, locate the corresponding channel on the Output page and enable Reverse.

(2) Check stabilization correction direction. Hold the aircraft in different attitudes to simulate flight. For example, pitch the nose down and verify that the control surface deflects upward to command a nose-up correction toward level flight. Test roll and yaw corrections in the same way.

(This check confirms that the flight controller output and servo response agree. If control-surface feedback is still inconsistent, repeat the checks in 2.1 Radio Transmitter Calibration and verify the servo wiring.)

5.3 ESC Calibration

On the AGC ground station Flight page, use Force Arm in the upper-right corner.

a. Confirm that the radio transmitter has been calibrated, switch it to VTOL stabilized mode, and move the throttle to maximum.

b. Hold the arming control fully left for 5 seconds to force arm. Important: remove all propellers during this test.

c. Connect battery power to the flight controller. After the ESC emits two beeps, move the throttle to minimum.

d. ESC calibration is complete. Raise the throttle slightly and verify that each motor rotates in the direction required by its propeller. If a motor rotates incorrectly, swap any two of that motor's ESC phase wires to reverse its direction.