Radio Controlled/Wireless Coconut harvester is a very helpful machine to harvest a lot of coconut fruit without risking the health or lives of any harvester by climbing the coconut tree and harvest the coconut fruit. Wireless coconut harvester is Arduino based that will program using the Arduino Ide in C++ programming language.

Wireless Coconut harvester is divided into 2 (two) parts: Transmitter and Receiver

TRANSMITTER BOARD

The transmitter board is powered by 2 (two) 3.7V Li-ion batteries (7.4V) and all of the Input devices are connected to this board,

The board is shaped like a usual transmitter. The Nrf24l01 transceiver module connects to the receiver at the highest range of 1200 meters. The standard tall of the coconut tree in the Philippines are 50 to 60 feet (15 to 18 meters) Therefore the range of this transceiver module is quiet enough to transmit data from transmitter to receiver. The total consumption of the transmitter board is less than 1 watt.

2 Joysticks - Robotic Arm

1 Joystick - Turning Mechanism

1 Joystick - Vertical Movement

Speed adjust (2 Pushbuttons) -Speed of motors in Vertical Movement

Potentiometer - Servo (Up and down)

Potentiometer - Servo (Left and Right)

Components list:

PCB WAY- Printed Circuit board X1

Arduino Nano X1

Nrf24l01+pla X 1

Potentiometers X 2

Pushbuttons X 6

Joysticks X 4

100uf/16V Capacitor X1

470uf/16V Capacitor X1

Toggle switch (mini) X1

10K ohms Resistors X6

2x 3.7V Li-ion battery holder X1

3.7V Li-ion battery X2

RECEIVER BOARD

The receiver board is powered by a 19V power supply in the video but in the actual plan, it should be powered by a 32650 LIFEPO4A Battery 4s10p with BMS and an active balancer. Each battery has a 3.2V nominal voltage, To get 12V DC, I need to series a 4 pcs of 32650 battery, to double the current rating I parallel 10X of 4pcs series 32650 LIFEPO4A battery (4 series 10 parallel)

The capacity of this battery is quietly high 12V 60AH (720W), therefore the coconut harvester can last up to 2 to 3 hours when all the loads are all running since the total computation of load are almost 300WH (25A) but in reality, when the coconut harvester machine are working not all the loads are running, therefore the consumption is less than 300 watts.

The main brain of this board is the Arduino Mega microcontroller.

The Nrf24l01 + PLA transceiver module connects to the receiver at the highest range of 1200 meters. The standard tall of the coconut tree in the Philippines are 50 to 60 feet (15 to 18 meters) Therefore the range of this transceiver module is quiet enough to transmit data from transmitter to receiver.

To power up my 4 pcs Nema 17 Stepper motor, I'm using a boost converter (step-up) 300W by using this can I select the voltage much higher to lessen the ampere flowing to the wire and to the coil winding of the stepper motor. By supplying a higher voltage like 24V DC to 35V DC the stepper motor lessens the heat while operating. Stepper motors are faster to heat up when the voltage is quietly low because the ampere is getting higher that's why the winding inside of the stepper motor cannot handle it.

To power the Arduino mega microcontroller, I connect an LM2596 buck converter (step down) to the output of the boost converter which is 24.5V DC to convert it to 5V DC. I decided to use this buck converter because of its high ampere rating (5A) therefore It can compensate for the power required by the Arduino mega as well as the 2pcs of Servo motor.

The coconut harvester has different portions: Vertical movement, Turning mechanism, Robotic Arm, Saw blade cutter. Camera Positioning.

Vertical Movement

The vertical movement is responsible for the up and down movement of the machine to the coconut tree. The motor used is the TAKANAWA Dc gear motor. It can lift up 60Kg at 24V and the driver for the motor is a BTS760 motor driver.

Turning Mechanism

The turning mechanism is in charge of the 360 rotation of the coconut harvester machine, for it to be flexible in any position to easily harvest a coconut fruit. The motor used is the TAKANAWA Dc gear motor.

It can lift up 60Kg at 24V and the driver for the motor is the L298N motor driver.

Robotic Arm

The robotic arm is consists of 4 joints; Base, Shoulder, Elbow, and Wrist, these 4 joints are controlled by each of the Nema 17 Stepper motors. The driver used for that is TB6600 and A4988 stepper driver. The main chassis of the robotic arm are plan to be made by 3D printing. The robotic arm is used to position the Sawblade cutter to cut accurately the stem of coconut fruit to harvest it.

TB6600 STEPPER DRIVER

You can achieve the step of the NEMA 17 stepper motor by setting up the dip switch attach to the driver, to select FULL STEP and 1 AMPERE RATING you should ON the 1,2,4, and 6 dip switch.

A4988 for NEMA 17 Stepper motor for wrist joint, since the wrist is the last joint it carries a lesser load compare to the other joints, therefore it requires a little bit power to operate it.

Saw Blade cutter

The saw blade cutter is used for cutting the stem of the coconut fruit to harvest it, it is accompanied by a relay module to On and Off this

cutter.

Camera Positioning

The camera positioning is controlled by two Servo motors (MG960), each of the servo motors is responsible for the angle position it either Left or Right and Up and Down. It helps the harvester to have a clear vision despite being in a lower ground position with the help of a wireless camera attached to the robotic arm, camera capture/video output transmit to the mobile phone.

Components/ Material list:

PCB WAY- Printed Circuit board X1

Arduino Mega X1

Nrf24l01 X1

2 pin terminal block X8

4 pin terminal block X6

Female and male header

A4988 stepper driver X1

1000uf/16V Capacitor X1

470uf/35V Capacitor X1

TB6600 stepper driver X3

BTS760 motor driver X1

L298N motor driver X1

LM2596 Buck converter X1

300W Boost Converter X1

Load components:

TAKANAWA DC gear motor X2

Servo motor (MG966) X2

555 Dc motor X1

NEMA 17 Stepper Motor X4

I developed the Fail safe system: If the short circuit or loss connection happened, the coconut harvester machine will automatically going down therefore, the machine will not be stuck to the tree. I planning to build the entire machine and test it on the Coconut field.

Soon you will see it helping our coconut harvester, climbing at the tree, and harvest a lot of coconut trees.

#Coconut harvester #Radio Control #Arduino #Nrf24L01 #Robotic theme