Gamepad

description of the file gamepad.py

The class Gamepad handle event from the Logitech Gamepad F310 connected by USB to topside computer. Build to test ROS implementation before we can connect ROS in parallel of QGroundControl (QGC).

If you launch QGC at the same time of ROS : Disable gamepad from QGC or not launch the gamepad file.

Library

The class Gamepad uses the library input from https://github.com/zeth/inputs to handle gamepad joystick and buttons.

This library comes with the github ROS repository but you will need to build it by

cd PATH2package/src/controllers/inputs
python setup.py install

Otherwise you can install it with pip:

pip install inputs

Logitech F310

Be sure that the slider at the back of the controller is at D side

How it's working

The inputs library provides API to handle the events from gamepad. Based on the event's name, a dictionary provide a link between the name of the event and the method to call.

Assignation table

Gamepad event name	Method called	Designation	Value	ArduSub/MAVlink id
ABS_Y	_throttle	LEFT stick vertical	[0-128-255]	clicked Joy : 7
ABS_X	_lateral	LEFT stick horizontal	[0-128-255]	clicked Joy : 8
ABS_RZ	_forward	RIGHT stick vertical	[0-128-255]	/
ABS_Z	_yaw	RIGHT stick horizontal	[0-128-255]	/
ABS_HAT0Y	_NDEF	LEFT cross vertical	-1 up; 0 neutral; +1 down	up : 11 ; down : 12
ABS_HAT0X	_set_gain_light	LEFT cross horizontal	-1 up; 0 neutral; +1 down	left : 13 ; right : 14
BTN_TRIGGER	_override_controller	X	0 ; 1	2
BTN_TOP1	_NDEF	Y	0 ; 1	3
BTN_THUMB	_NDEF	A	0 ; 1	1
BTN_THUMB2	_NDEF	B	0 ; 1	0
BTN_BASE	_NDEF	LT	0 ; 1	/
BTN_BASE2	_NDEF	RT	0 ; 1	/
BTN_TOP2	_cam_down	LB	0 ; 1	9
BTN_PINKIE	_cam_up	RB	0 ; 1	10
BTN_BASE3	_disarm	BACK	0 ; 1	4
BTN_BASE4	_arm	START	0 ; 1	6

ROS

Node

Gamepad

Topics

ROS topics subscribed	Message	Description
/BlueRov2/arm	Bool	The arm status

ROS topics published	Message	Description
/Command/joy	sensor_msgs/Joy	axes : [THROTTLE, YAW, FORWARD, LATERAL] buttons : [ARM, OVERRIDE_CONTROLLER, PWM_CAM, LIGHT_DEC, LIGHT_INC, GAIN_LIGHT]

Joy message parameters	Type	Description
THROTTLE	Float32	pwm : Uint16 [1100-1900]range
YAW	Float32	pwm : Uint16 [1100-1900]range
FORWARD	Float32	pwm : Uint16 [1100-1900]range
LATERAL	Float32	pwm : Uint16 [1100-1900]range
ARM	Int32	0 : disarm ; 1 : arm
OVERRIDE_CONTROLLER	Int32	0 : AUTOMATIC mode, 1 : MANUAL mode
PWM_CAM	Int32	pwm for camera tilt
LIGHT_DEC	Int32	1 if you want to decrease brightness, else 0
LIGHT_INC	Int32	1 if you want to increase brightness, else 0
GAIN_LIGHT	Int32	result of gain light

The LIGHT_DEC, LIGHT_INC, GAIN_LIGHT parameters are not used