********************************
ATCrawler Basic with Cubepilot
********************************

The ATCrawler basic assemble set allow you to use Cubepilot as a flight controller.

Once you have the ATCrawler basic with you, it would come with our custom ESC for high power driven motors the **AT_MOTOR-DRIVER_100A_2ch_ver.9.0** with aluminum heatsink attached on the box's lid.

To use ATCrawler basic as ArduRover for Ardupilot, please follow the connection diagram below.

    .. image:: images/atcrawler_cube_connection.jpeg
        :width: 1024px
        :align: center

From the diagram, CUBE Orange is used but you can use any model of Cubepilot. 

* From CUBE **MAIN OUT CH1** -> ESC **PWM1**
* From CUBE **MAIN OUT CH3** -> ESC **PWM2**
* From CUBE **AUX OUT CH1** (SERVO9) -> ESC **PWM3**

.. note::
    This **AT_MOTOR-DRIVER_100A_2ch_ver.9.0** has two control methods, 
    
    1. to control by PWM signal (PWM ports)
    2. to control by ROS topic (USB port). 

    In order to use it in PWM mode, ESC **PWM3** has to be on PWM neutral (~1500us), and that's why we need **AUX OUT CH1** as extra pin.

Ardupilot Parameters
######################

Similar to other PWM driven ESC vehicle, we need to specify the servo output according to rover frame type. The ATCrawler basic is working similar to skid-steer rover.

* `SERVO1_FUNCTION <https://ardupilot.org/rover/docs/parameters.html#servo1-function>`_ = 73 (Throttle Left)
* `SERVO3_FUNCTION <https://ardupilot.org/rover/docs/parameters.html#servo3-function>`_ = 74 (Throttle Right)
* `SERVO9_FUNCTION <https://ardupilot.org/rover/docs/parameters.html#servo9-function>`_ = 135 (SERVOn_TRIM)

When Cube is booted up, the AUX CH1 or SERVO9 will output neutral PWM signal then the ESC will be changed to PWM control mode.

For other parameters, it has the same setup process as explain on Ardupilot documentation `First Time Setup <https://ardupilot.org/rover/docs/rover-code-configuration.html>`_, please setup other peripheral such as Radio, telemetry, GPS, compass, and etc.