How to build DIY Arduino Transmitter OpenTx firmware

        Instruction "How to build  DIY Arduino Transmitter OpenTx firmware" will describe how to build 2.4G 8-channel DIY transmitter using MEGA2560 Arduino controller installing OpenTx firmware which similar to commercial transmitter in the market.       

       The Arduino MEGA2560 will produce traditional PPM signal to send to RF module that can  communicate to general transmitter modules like Frsky,Flysky,Orange,..etc.
        Difficulty : Hard
Materials
1. 1 - Arduino controller - MEGA2560 Core











2. 1 - 128x64 LCD display  12864ZW with ST7920 controller

3. 1 - Old RC transmitter body

4. Joy stick gimbals.(mode1,mode2)

5. Push buttons

6. Capacitors - See detail in BOM

7. Diode 1N4007

8. 1 - 7805 IC Regulator 5V.

9. Female pin header

10. Double rows female pin header

11.Single row male pin header

12.Single row long male pin header

13. Double rows male pin header

14. 1 - LED 5 mm.

15. Resistors

16. Ribbon wires.

17. Male JST Battery Pigtail

18. Heat shrink tube 1.5 - 10 mm.

19. Velcro tape

20. 1 - PCB.DIY. circuit board

21. Battery Lipo 7.4V.1000 mAh (2cells)

22. Electrical 26 AWG wires

23. 1 - Piezo speaker

24. 1 - Transmitter module.(PPM)

25. 1 - Card reader Arduino

26. 1 - SD card

27. Rotary Potentiometer B10K

Tools

1. Soldering gun

2. Soldering wire

3. Soldering paste

4. Screw driver

5. Plier

6. Hot glue gun

7. Epoxy glue

8. Two sides glue tape

9. Plastic cutter

10. Electrical drill

DIY PCB building

1.Installing electronic parts on DIY PCB according to electrical circuit diagram.(see in Github)
2.Install switches,joy stick gimbals,push buttons on transmitter body.

3.Wiring and connecting PCB - MEGA2560 - Gimbals - Switches - Push buttons according to circuit diagram.

Firmware installation (can do before hardware installation)

1.Downloading software OpenTx companion2.2.x from OpenTx website.

2.Installing OpenTx companion on PC.

3.Running OpenTx companion,downloading firmware by using OpenTx companion.

   3.1 Edit setting menu 
      - Radio type : DIY MEGA2560 radio
   3.2 Build option 
      - ST7920
      - frsky
      - sdcard
      - more option as you want

    3.3 Default Stick Mode(Futaba)
      - Mode3 (AIL ELE THR RUD) 
    3.4 Default Channel Order (Futaba)
      - A E T R
4.Flashing Arduino MEGA2560 by using usbtiny.
    See detail of flasing procedure in Github.

5.Testing hardware post-installation.

How to Build Gripper Tracked Robot Via Nrf24l01 Arduino

          Instruction "How to Build Gripper arm Tracked Robot Controlled Via Nrf24l01 Arduino" will explain how to build a three degree of freedom gripper arm installed on tracked wheeler driven by dual motor drive L298N module using MEGA2560 Arduino controller.The gripper arm and robot movement will be remoted by 8-channel transmitter(see instruction "How to Build 8 Channel Transmitter nrf24l01 Arduino")

Materials

1. 1 - Arduino controller - MEGA2560

2. 1 - NRF24L01 module

3. 1 - Socket adapter for NRF24L01(For protect & stabilize NRF24L01 module)

4. 1 - LED 5 mm.

5. 1 - Resistor 1 kOhm. 1/4 watt.

6. 1 - Capacitor 0.1 microF /50V.

7. 1 - Capacitor 1 microF /50V.

8. 1 - Capacitor 100 microF /50V.

9. 1 - Diode 1N4007

10. 1 - 7805 IC Regulator 5V.

11. Ribbon wires.

12. Female pin header

13. Male pin header

14.1 - Dual motor drive L298N module

15. Male JST Battery Pigtail

16. Heat shrink tube 1.5 - 10 mm.

17. Velcro tape

18. 1 - PCB.DIY. circuit board

19. Battery Lipo 11.1V. 2200 mAh (3 cells)

20. Tracked wheel toy with dual motors

21. Electrical 26 AWG wires



22. Acrylic sheet 5 mm. thickness

23. Bolts M3

24. Nuts M3

25. Tapered head self-tapping screw

26. 1 - Three degree of freedom gripper arm

27. Dean plug

Tools

1. Soldering gun

2. Soldering wire

3. Soldering paste

4. Screw driver

5. Plier

6. Hot glue gun

7. Epoxy glue

8. Two sides glue tape

9. Plastic cutter

10. Electrical drill


11. Hack saw

Mechanical parts installation

1.Cut and drill acrylic sheet to make platform base for equipments installation.(As your own design) Example base plate drawing:

2.Fix acrylic sheet on tracked wheeler by self-tapping screws.

3.Fix gripper arm on base by M3 bolts and nuts.

4.Install L298N module on base by two-side glue tape.

5.Glue and paste velcro on acrylic base and battery.

Electronic parts installation

1.Making DIY PCB and wiring,soldering as above circuit diagram.

MEGA2560 pins to nrf24l01 module :

GND - GND

3.3V. - Vcc

9 - CE

53 - CSN

52 - SCK

51 - MOSI

50 - MISO

2 - IRQ

MEGA2560 pins to L298N module :

3 - ENA

4 - IN1

5 - IN2

6 - IN3

7 - IN4

8 - ENB

MEGA2560 pins to three servoes of gripper arm :

11 - Arm1

12 - Arm2

13 - Gripper

6.Assembly PCB on MEGA2560,putting pins on the correct headers as circuit diagram.

7.Wiring and connecting three servoes of gripper arm to PCB.

8.Attach MEGA2560 board on acrylic base by two-side glue tape.

9.Wiring dual motors to L298N module.

10.Checking and finding short circuit points.(beware of high current electrical short circuit ,will caught fire)


11.Testing the direction of motors and gripper arm servoes.

Sketch uploading

1.Download sketch from Github.

2.Upload to MEGA2560 controller.

3.Test controlling between transmitter and gripper arm tracked robot.

Remarks : If the nrf24l01 module had never bound before see how to pair frequency in video clip.

AliExpress.com Product - JEASUNG P8 Waterproof new mobile phone IP68 4G Shockproof Phone 2G RAM 16GB ROM Smartphone 5" NFC Fingerprint PTT IP67 Phone

AliExpress.com Product - Touchscreen Colourful Programmable Room Thermostat for Electric Heating (with Modbus function)