Skip to content
Lab 11 Motors and Controls (Continued)
AT209 – Believer Avionics
Group 4 – Nolan Lach, Jacob Sieber, Ryan Pirro, Elijah Meadows, Madison Baker, Venkata Devapatla
Introduction
In this lab, we focused on getting the Believer’s motors and controls up and running. We calibrated the DATX controller, mapped our channels, checked servo movement, and powered an ESC + motor setup to make sure everything responded the way it should. This was our first real look at how the Believer will actually move once it’s in the air.
DATX Calibration and Binding
We began by powering on the DATX and confirming where the controller believed the sticks were positioned. After entering the Hardware menu, we performed a complete stick calibration and verified that the on-screen indicators matched the physical movements.
Next, we used the LUA script to open the Tracer Micro TX menu and completed the binding process with the Nano RX. The screen showed Binding OK, confirming the transmitter and receiver were paired correctly.
Figure 1. DATX calibration and binding process
We then navigated to the Tracer Nano RX → Output Map and set Output 1 to SBUS. This is important because the Cube expects a single-wire SBUS signal through the RCIN port. The other channels were left unchanged.
Figure 2. SBUS mapping on the Nano RX
Mapping Parameters & Avionics Integration
Once the receiver was configured, we connected it to the full avionics mock-up with the GPS, airspeed sensor, telemetry radio, and Nano RX into the Cube. After powering the system, we confirmed sensor status using the Ground Control Platform Health window.
We then recorded the required RC and servo configuration parameters:
Parameter and Mapping
Name
Current Setting
Column 3
Notes
SERVO1_FUNCTION
FlaperonRight
Open
SERVO2_FUNCTION
FlaperonLeft
Open
SERVO3_FUNCTION
Throttle
Open
SERVO4_FUNCTION
Throttle
Open
SERVO5_FUNCTION
VTailLeft
Open
SERVO6_FUNCTION
VTailRight
Open
SERVO7_FUNCTION
RUDDER
Open
RCMAP_BRAKE
0
Open
RCMAP_FLAP
5
Open
RCMAP_PITCH
2
Open
RCMAP_ROLL
1
Open
RCMAP_THROTTLE
3
Open
RCMAP_YAW
4
Open
There are no rows in this table
The RCMAP assignments tell the Cube which incoming channel corresponds to which flight control command, and the SERVO functions determine which control surface receives the corresponding control.
Controller Input
Input
Output
Notes
Right Stick
Flaperon Left &Right, VTail Left & Right
Open
Left Stick
Flaperon Left &Right, VTail Left & Right
Open
Pitch Up
Vtail Left & Right
Open
Pitch Down
Vtail Left & Right
Open
Throttle Up
Servo Output 3/4
Open
Throttle Down
Servo Output 3/4
Open
There are no rows in this table
This mapping allows us to visually confirm that the stick movements on the controller properly correlate with the flight control servos, by having corresponding names and seeing if the right servo moves with the controls.
Motor and ESC Setup
Once servo behavior was verified in Ground Control, we connected one servo and one ESC to the correct outputs based on our tables. At first, the servo did not move—this was expected because the servo rail was not powered yet.
After powering the ESC with the bench supply (set to ~22V to emulate a 6S LiPo), the ESC’s built-in BEC delivered the required 5V to the servo rail. At that moment, the servo responded exactly as expected.
We mounted the ESC and motor to the thrust stand and then performed an ESC calibration following the manufacturer instructions plus the ArduPilot requirement of being armed in Manual mode during calibration. After calibration, we were able to smoothly ramp the motor from zero to full power.
Figure 3. Bench-top avionics and ESC testing setup
Reflection
This was one of the most engaging labs we have had so far. Learning how to power the motors and the types of redundancy in place was great information to learn. After this lab I feel confident in my ability to continue to build avionics systems and most importantly troubleshoot them. I’m looking forward to integrating the avionics and controls into the aircraft and eventually flying it.
Want to print your doc?
This is not the way.
This is not the way.
Try clicking the ··· in the right corner or using a keyboard shortcut (
CtrlP
) instead.