ESP32 3D Printed Helicopter!!!

Hello!

Below is the visual Guide on how I built an ESP32 3D printed RC helicopter. I have taken ~300 pictures of how I made this helicopter, so you can follow along with the images and the image descriptions to help you build this helicopter. This helicopter was originally based on a heavy 18650 4S3P battery, which only let the helicopter fly once due to its max ~40A output, but for the sake of the people following this instructable, I will be using a 4s 18650 to test the electronic desgine so the people following this instructable can use a 120A 4s lipo battery that I have provided the link in the Supplies part of the instructable. I can also confirm that the flybar mechanism works well from the one time the helicopter flew. Speaking of flybar, I was inspired by this awesome flybar design and this helicopter with 3d printed parts, so big credit to Navid Goudarzi and Life Around Damian for inspiration.

Important info:

1. Print Settings
2. I used 1 wall and 10% line infill to make the printing process speedy, but I have also used 100% infill on the parts that need a lot of strength.
3. Print tolerances
4. The free spinning tolerances of the printed parts are 0.2mm, but I have also put some direct M3 screw to the plastic free spinning joints (don't worry, they have a surprisingly long lifetime), and the diameter of those holes is 3.4mm. And I did notuse lock-tight, so in each hole a screw goes in, the diameter of the hole is 2.7mm to ensure the screw does not get loose.

Enough with the boring info, it's time to have fun assembling the helicopter and hoping no magic smoke comes out during the electronics part.

Here are the supplies, which together cost less than dinner but somehow more than my dignity.

Screws And Bearings

1. 6 of M3x5mm Screw
2. 2 of M3x20 screw
3. 180 M3x10mm Screws
4. 180 Square nuts
5. 2 608 bearing
6. 1 big 6006 bearing

Things that must be cut

1. 10x10 and 200mm long square wooden rod
2. 11mm thick wood
3. 4mm steel rod
4. 3mm steel rod

Electronics

1. ESP32-S3
2. Red Brick 100A esc
3. HW30A esc
4. 4S Li-Po Battery
5. 2 of ZD2808-V1.9 700kv motor
6. Servo motor

This part holds the entire helicopter mechanism and houses the servo motors

Images 1 to 3:

Insert 6 square nuts on the top servo holder; there are 6 slots on the top of it where square nuts are hammered.

Images 4 and 5:

Put square nuts in the servo horn

Image 6-7

Angle the servo to 90 degrees and screw in the servo horn

Images 8 and 9:

screw the servos to the top servo holder

Images 8 to 11:

hammer bearings in the bottom servo holder

Note:

I didn't take a picture of this during the documenting of the assembly step, but in the Bottom servo holder, there are 9 slots to insert square nuts(6 at the near the bottom and 3 near the top)

Images 12 to 15:

Insert 2 square nuts in the slots that are on the bottom of the big gear center and screw the M3 screws into the holes that are on the side of the big gear center

Images 16 to 18:

Insert the 4mm steel rod through the big gear centre and tighten the screws in the big gear center

Images 19 and 20:

Insert the axle adapter on the axle, on top of the big gear center

Images 21 and 22:

hammer the axle in the 2 bearings in the bottom servo holder(ignore the placement of the top servo holder because I messed up in documenting the assembly step)

Images 23:

Insert 2 square nuts in the slots on the top of the axle thingy(I should have called it axle holder) and put 2 M3x5MM screws in the part

Images 24 and 25:

insert the axle thingy(REMBER TO PRINT THIS WITH 100% INFILL!!!) on the 4mm rod and tighten it

Images 26 to END 🎉👍

Screw the top servo holder onto the bottom servo holder

Yay, we have completed the Servo Housing!! (∩_∩)

Image 1:

insert a square nut in the Bottom swashplate translator

I forgot to take pictures of this step:

in the bottom swash plate there is 2 square nut slots on the bottom of the model and on the sides of the arms

Images 2 and 3:

screw the Bottom swashplate translator on the bottom swashplate

Images 4 and 5

screw the bottom swashplate arms on the bottom swashplate

Images 7 and 6:

screw the m3 standoff on the Bottom swashplate translator

Image 8:

hammer the 6006 bearing into the bottom swashplate

Image 9 and 10:

hammer the upper swashplate on thee bottom swashplate

Images 11 to 15:

put the swashplate on the 4mm rod and screw to the servo horns on the servo housing

Images 1 and 2:

Insert 2 square nuts into the flybar slider and screw 2 screws in

Images 3 and 4:

screw a screw into the bar

Image 5:

Put a spacer on the screw

Image 6:

screw another bar on the screw

Image 7:

Tighten everything up using a square nut

Images 8 and 9:

screw that bar on the flybar slider and tighten with a nut(the bar must rotate smoothly for the helicopter to function). Images 10 and 11:

screw the assembly to the upper swashplateto the o flybar slider arm and tighten using the nut(this also needs to rotate smoothly)

Image 12:

Repeat for the other side of the flybar slider

Images 13 to 17:

Insert the assembly on the 4mm rod and screw it on the upper swashplate

Bottom Swashplate Keep Still Mechanism:

Images 18 to 23:

Put square nuts in the grooves of the bottom servo holder and screw the bottom servo holder in place. Don't worry,y we will position it precisely in the future.

Images 24 to 2

Shimmy the bottom swashplate. Keep still in between the M3 standoff on the bottom swashplate and move it next to the bottom servo holder.

This is just a 2 axis gimble that holds the flybar airfoils, and it is an important part of the flybar mechimsm

Image 1:

Insert 2 square nuts in the flybar slider

Images 2 and 3:

screw the flybar slider to the flybar x rotater using M3x7MM screws(the flybar x rotater should rotate smoothly)

Image 4:

Place 6 square nuts in the slots of the flybar y rotater(print this part with 100% infill)

Images 5 to 9:

Place the flybar X rotater in the flybar Y rotater and insert the 3mm rod through the flybar X rotater and the flybar Y rotater and tighten the screws VERY VERY HARD; otherwise,e the rods will fly out when it is spinning. Repeat for the other side.

Images 10 to 13:

screw the Bottom flybar arm on the top flybar arm and tighten it in place using a nut to make a flybar arm

Images 14 to 18:

Put the Flybar Arm on the 3mm rods with the Thin Spacers.

Images 19 to 24:

Put the flybar airfoil on the 3mm rod and use the Flybar Airfoil Centring Block to ccentrethe airfoil perfectly with the Flybar Y Rotater.

Images 25 to 27:

Put screws in the Upper swashplate to the flybar gimble arm, and insert square nuts on the screws and screw that to the Flybar Gimble.

Images 28 to END

Screw the Upper swashplate to the flybar gimbal arm to the flybar assembly.

This holds the helicopter blades like a Samurai, and it also has a linkage that averages the swashplate output and the flybar output (Note: all of these parts must be printed with 100% infill except for the 2 Output Adder).

Images 1 to 4:

Insert 4 square nuts in the Blade Centre (2 slots on top and 2 slots on bottom), and also insert 2 square nuts into the Samurai

Images 5 to 8:

Screw the Samurai to the Blade Centre (Note: the Samurai needs to rotate smoothly)

Images 9 to 13:

Insert 2 square nuts in the 2 Output Adder and screw those in place on the Samurai

Images 14 and 15:

Screw Screws(is my Grammer correct?) into the Blade centre, don't screw fully in, screw halfway to allow the 4mm rod to go through the Blade Centre

In this step, we will be putting the Flybar Gimble and the Samurai Blade Holder on the 4mm rod.

Images 1 to 5:

Slide the Flybar Gimble on the Flybar Slider and screw the Flybar Gimble on the Upper swashplate, and do the same for the other side.

Images 6 to 11:

Drop the Upper Swashplate to Samuari arm in between the Flybar Gimble and screw it to the Upper Swashplate, and repeat for the other side.

Images 12 to 14:

Slide the Samurai Blade Holder on the 4mm rod and screw the Upper Swashplate to Samuari arm on the 2 Output Adder(Note: the Upper Swashplate to the Samurai arm must rotate smoothly), and repeat for the other side of the Samurai Blade Holder.

Images 15 to 19:

screw the Flybar Arm to the 2 Output Adder and repeat for the other side

We are fully done with the Mechanism (◕‿◕✿).

Images 1 to 3:

Put 8 Square nuts in the slotson the Second Battery Holder, as demonstrated by the Image and screw the screws through the nuts.

Images 4 to 6:

Slide the 15mm hollow rod through the Second Battery Holder and tighten the screws to lock the 15mm hollow rod in place.

Images 7 to 9:

Put 4 square nut in the Back Motor Holder

Images 10 to 13:

Screw the Back Propeller to the motor, and then screw 2 screws into the Back Propeller.

Images 14 to 16:

Insert 8 screw into the Front Motor Holder and then screw the holder to the motor

Images 17 to 23:

Put the front motor holder on the 15mm rod, and place the back motor holder on the other side of the rod, and tighten the screws on the Front Motor Holder into the back motor holder.

Landing Legs

Image 24:

Cut an 11mm thick wooden plank into a 305mm to 30mm rectangle and drill two 3mm holes into it as demonstrated by the Image. Make 2 of these.

Images 25 and 26:

Put square nuts in the Back Landing Leg Holder and screw it to the wood rectangle. Make 2 of these.

Images 27 and 28:

Screw the Back Landing Leg Holder with the wood rectangle and screw it to the 10x10mm square wooden rod next to the Servo Housing, and put the second one on the other side of the helicopter.

Images 29 to 31:

Put the back arm on the 10x10 wooden rod and tighten it in place.

Last step:

Move the Servo Housing and the 2 Back Landing Leg Holders 9mm away from the Back Arm and tighten them.

Images 1 and 2:

Put 2 screws in the Small Gear and screw the gear on the motor axle

Images 3 and 4:

Tighten the Screws on the gear

Images 4 to 8:

Put the big gear on the big gear hub and lock the gear in place using 4 screws

Images 9 to 12:

Put 5 square nuts into the Front Landing Leg Holder, print 2 of these

Images 13 to 19:

screw the motor on the motor block with a spacer

Images 20 to 24:

screw the motor block the 2 Front Landing Leg Holder

Images 25 to 30:

screw the assembly on the 4 wooden rods.

It's time to release magic smoke.

First, download Thonny and MicroPython by following the YouTube tutorial link here.

With the esp32 that you are planning to use in the helicopter, run this code and write down its output

The output should be something like this -> b'\xft\x01,-\x5fP'

When you are done with that, I have a file called helicopter.py, run that and save that file on the esp32 as boot.py.

Tape the HW30A to the back arm to ensure good airflow for the HW30A in Image 2.

Connect everything, referring to the wiring diagram spreadsheet above in Image 1.

Your setup should look like Image 3.

Remember to insulate the wire connections using hot glue or electrical tape

Connect batteries and main motor

this is a step by step tuturiol because i forgot to take pictures(my phone ran out of battery)

1. connect main motor to 100A ESC(it does not matter the order in witch you place them because we will doudle check if the motor is spinning the right way later)
2. connect the negative side of the esc to the negative side of the 4S lipo
3. connect a switch to the positive side of the 100A ESC
4. connect the switch to the negative side of the 100A ESC

do the same thing except replace 100A ESC to HW30A, replace main motor to tail motor and replace 4s lipo to 3s lipo in the step by step tuturiol.

turn on both switches at the same time and if you hear one beep and a pause and a beep again from both motors then you have done it correctly but if there beep beep beep with no long pause double check the esp32 pinout and flash the helicopter.py code to boot.py again.

Organize Electronics

First start with putting the 3S battery in the Second Battery Holder and use velcro to lock it in place like in image 4 then put the 4S lipo and the esp32 in the electronic box the close it using 4 screws like in Image 5.

Yay we are 100% done with the Helicopter but now it time for the hard part witch is the receiver.

Images 1 to 6:

Place the ESP32 and the joystick on the body of the remote, and screw the top cover in place. If needed, put nuts on the screws to tighten the body to the top cover

Images 7 to 10:

Put a nut in the slot on the potentiometer holder, and then screw a screw through that nut, and then put the potentiometer in the hole and tighten the screw.

Images 11 to 14:

screw the potentiometer holder to the case and tighten it using nuts

Images 15 and 16:

Wire it according to the wiring diagram

Images 17 and 18:

Put battery straps on the back cover

Images 19 to 23:

screw the back cover to the body and put the battery on the remote.

Using Thonny, flash the joystick.py file as boot.py on the remote's ESP32 and change the peer variable on the 13th line of code to your Helicopter's MAC address.

WEAR SAFETY GLASSES!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Now it is testing time, to connect the helicopter to the remote, first turn on both switches at the same time, then when the beeping stops, connect the ESP32 on the remote to the power bank on the remote and then when you connect the ESP32 to the power bank, you will see the tail motor go to 50% automatically and if its spinning the wrong direction then offf the helicopter and the esp32 and switch 2 wires around from the motor to the esc to change direction. When it starts spinning in the right direction, then increase the throttle SLOWLY by spinning the throttle knob counter-clockwise, and if that is spinning the wrong direction, switch 2 wires around from the motor to the esc.

Now you can put the blades of the helicopter by using 2 M3x20 screw(Note: if the blades appear small in the slicer, then scale them by 1.5 times)

Here is the link for the helicopter blades.

If you are having trouble printing helicopter blades, then refer to this YouTube video.

If you don't know how to fly an RC helicopter, then watch this YouTube video on how to fly a helicopter.

Have fun with your RC Helicopter!!!!!!!!!!