About this project

Goals:

About this project

Click to see video: http://www.youtube.com/watch?v=lwrkspHjSu4

The goal is to build quadcopter based on ESP32 microcontroller, Eachine E58 motors and 3D-printed shell.

Drone can be controlled with Dualshock 3 gamepad, or DIY controller based on https://github.com/RomanLut/hx_espnow_rc

Firmware is Mahowii port for ESP32.

Mahowii is modified Multiwii firmware enchanced for quadcopters. Original Mahowii repository: https://github.com/mahowik/mahowii

Changes implemented:

ESP32 port code fixes (32 bit arch fixes, EEPROM stub)
PlatformIO project setup
Added PS3 controller rx
implemented bluetooth serial communication for EZGUI
implemented changes for specific hardware ( brushed motors, arm leds )
added blackbox (Cleanflight format)
added WifI softAP and ftp server (for blackbox)
changed altitude mode: throtle controls target altitude
changed maghold mode: yaw stick controls target direction
adjusted default PIDs
control and MSP communication with HX_ESPNOW_RC library https://github.com/RomanLut/hx_espnow_rc
disabled GPS code

This project requiers understading of multiwii basics. You will have to make it work for you. No step-by-step build guide is provided here.

Connection diagrams

EZ_GUI connection

EZ-GUI application can be used to see telemetry and edit drone settings: https://play.google.com/store/apps/details?id=com.ezio.multiwii

This is optional. When you flash ESP32 first time, PIDs and AUX settings described below are applied.

If drone is controlled with Dualshock controller, connect directly to drone, which is visible as "QUADX" BLE device.

If drone is controlled with HX_ESPNOW_RC controller, you have to connect to RC Controller instead, because ESP32 can not handle WIFI and BLE simultaneously.

AUX settings

AUX1 Mid: Arm
AUX1 High: Arm
AUX2 Mid: Angle
AUX2 High: Angle + Alt Hold
AUX4 High: Beeper

PID settings

PS3 Controler

Drone can be controlled using Dualshock 3 gamepad (original only!).

Effective distance is <50m.

Refer to esp32-ps3 https://github.com/jvpernis/esp32-ps3 how to pair drone with controller.

Controls:

Arm/Disarm - Start. Arm with Throttle down!
Acro(Mode 0) - PS3 Left Thumb
Angle(Mode 1) - PS3 Square
Alt Hold(Mode 2) - PS3 Triangle

Dualshock 3 D-pad is used for ACC trim in flight.

Jumper T-Lite setup

Drone can be controlled by Jumper T-lite or similar controller with HX_ESPNOW_RC external module https://github.com/RomanLut/hx_espnow_rc/blob/main/doc/tx_external_module.md

Jumper t-lite have to be configured to use HX_ESPNOW_RC profile.

Effective distance is more then 200m.

Channel assignments:

AERT
CH5: SWC
CH6: SWA
CH8: SWD
CH9: MAX, Switch: tEu
CH10: MAX, Switch: tEd
CH11: MAX, Switch: tAu
CH12: MAX, Switch: tAd
CH16: MAX, Weight:0,Offset -80% ( hx_espnow_rc LR profile selection - profile 2)

Disable trims in FlightMode 0. Right stick trim buttons are used to trim ACC in flight.

Controls:

SWC - Arm
SWA - Acro / Angle / AltHold
SWD - Beeper
Right stick trims are used to trim ACC in flight.

Battery voltage, RSSI, height and other telemetry sensors are sent as SPORT telemetry.

Calibration

Gyro calibration

Performed automaticaly on power on.

Yaw left + Thottle Low + Pitch LOW.

Blue and red leds blinking fast.

Accelerometer calibration

Should be done once.

Yaw left + Throttle Hi + Pitch LOW.

Blue and green leds blinking fast

Simple procedure: Place on level surface, do not move.

This firmware also contains more precise calibration procedure:

Calibrate quad facing up, then calibrate quad facing down.

Arm LEDs colors

RC signal:

Front arms no lights - no RC signal
Front arms blue solid - ok RC signal

Battry status:

Back arms green: battery ok
Back arms yellow: battery near low
Back arms red: battery low
Back arms red blink: battery critical, land now

Calibration:

Red and Blue leds blinking fast: gyro calibration
Red and Green leds blinking fast: acc calibration

Blackbox

Drone can write blackbox log to SPIFFS filesystem in Cleanflight log format https://github.com/cleanflight/blackbox-log-viewer

To enable logging, uncomment #define BLACKBOX in config.h.

Logs can be downloaded using HTPP of FTP connection. Connect to drone's Wifi AP: user"quad", password:"12345678". Browse "http://192.168.4.1" or connect to ftp://192.168.4.1 using User: "anonymous", password: "anonymous".

Note: After creating/deleting files, SPIFFS filesystem became fragmented. It's perfomance will degrade and affect cycle time. Drone will start to "hickup". Log to fresh SPIFFS. To refresh SPIFFS, "Upload filesystem" using PlatformIO. Disable blackbox for normal usage.

Pin allocation

Used pins:

1 - TX0
3 - RX0
4 - Left Front Blue LED
12 - Right Front Blue LED
13 - Left Back, Right Back Green LEDS
14 - Right Back Red LED
15 - Left Back Red LED
21 - SDA
22 - SCL
36 - VBAT ADC
25 - Left back Motor
26 - Right Back Motor
27 - BUZZER EN
32 - Right Front Motor
33 - Left Front Motor

Free pins:

0 - (not available on 30 pin board)
2 - board LED_PIN
5
16 - RX2
17 - TX2
18 - SCK
19 - MISO
23- MOSI
35 - (inpput only)
39 - (input only)

STL files for printing

Solidworks 2018 drawings and STL files are available in Drawings folder and on Thingiverse https://www.thingiverse.com/thing:5460208

No GPS modes?

Originaly I had a plan to implement Poshold, RTH and Waypoint navigation. Mahowii has code for that. But due to various reasons I decided to abandon this functionality:

quadcopter does not have enough power to fight the wind
I do not have enought outdoor time in calm weather for PID adjustments and testing
GPS sensor is additional weight
I little bit tired to fix and enhance old code :( It is better to try Ardupilot ESP32 port https://github.com/sh83/ardupilot/tree/esp32/libraries/AP_HAL_ESP32

So I disabled GPS modes currently.

Old GPS wiring: https://github.com/RomanLut/mahowii/blob/upstream_shared/doc/gps_code/gps_code.md