DOPABOT

Happiness maker

In short words, it is a drawing robot that creates Pattern portraits using pen, paper, and an algorithm.

Hand drawing activates the Brain, boosts Creativity, and adds life to the content compared to computerized writing. Drawing created by pen increases memory and retention of feelings.

DOPABOT offers the combination between new technology and old-fashioned pen and paper has an immense impact on emotional well-being, helping us organize our thoughts and even improve our moods.

DOPABOT is a Happiness maker, which will help you in capturing unique moments and boost creativity.

My final project idea is to design, simulate, and build Wireless Pattern Making Robot ( DOPABOT). As an engineer, I love to discover the relationship between mathematics and art through patterns. So, I inspired the idea of the assignment from mathematical-based patterns that are found all around us in our daily lives as well as in nature. In this project, I worked to develop a Wireless robot to make beautiful patterns using a Bluetooth module controlled by a mobile APP. DOPABOT uses a cross-shaped structure and two stepper motors to create the patterns. The setup is designed to allow for multiple different movement patterns based on the configuration of the motors and the arm joints.

The design is made from wood where the plotter arm is controlled by two stepper motors, and the plotter based is rotated by the third stepper motor.

Software

• CAD Software: Fusion 360 is a cloud-based 3D modeling, CAD, CAM, and PCB software platform for product design and manufacturing. I used it to convert the sketch to a 2.5 D CAD model. And Also, it has been used to export the DXF file of the holder parts for laser cutting.

CAD process

Fusion 360 is used for designing the robot. The design consists of four main parts: the arm, the drawing plate, coupling, and the body.

• - The arm has consisted of two columns and two small circles

• - The drawing plate has consisted of two big circles

• - Three couplings are has consisted of a cylinder with small holes for mounting with the motor and one central hole for the shift of the motor.

• - The body has consisted of six rectangles:

1. The front rectangle with slots for motors, bottom, and LCD

2. The back rectangle with slots to fix the Arduino and motor drivers

3. The four side rectangles between the front and back with slots for the power source and ON/OFF switch.

The design steps for all parts are as the following ( as shown in the photos):

1. Sketch of the parts has been drawn in 2D at XZ.

2. The sketches have been extruded to 2.5 D bodies.

3. The components have been created from the bodies.

4. All components are assembled using the joint option in Fusion 360.

Software

• Cura is an open-source slicing application for 3D printers.

• Laser cut software: Laserwork (V6) is used to perform laser cutting engraving operations for the holder parts.

Machine

• Laser cut Machine : Morn MT3050D CO2 Laser Cutter used to cut and engrave the holder parts on the wood plate.

I used it for the following reasons :

• The control system of the machine has better hardware stability and better anti-high voltage and anti-static interference properties.

• Easy to learn.

• The software support Coreldraw, Photoshop, AutoCAD, etc

• The positioning accuracy can reach 40um.

• Less wear and tear, can keep accuracy for a long time.

• It is suitable for high-speed movement and greatly reduces the horsepower required to drive the machine table.

• 3D printer: Prusa i3 MK2 is one of the best 3D Printer in digital fabrication by MAKE

Materials

• 3mm Plywood. I used it because it is perfect for Arts and Crafts, makers and DIY projects, drawing, painting, wood engraving, wood burning and laser Projects

• Materials: ESUN PLA

The Filament features :

- Printing Temperature: 190-220℃

- Density: 1.43g/cm³

- Melt Flow Index: 2.5 (190°C/2.16kg) g/10min

- Tensile Strength: 58MPa

- Elongation at Break: 300%

Fabrication process

Laser Cutting

• LaserWORK has been used to perform the cut and engraving for the robot body and drawing plate. The process steps are as the following ( as shown in images)

1- DXF files of parts have been imported.

2- The construction lines have been deleted.

3- the parts have been moved near the original point ( corner point) to minimize the used wasted wood.

4- Two processes have been used, scanning for the name, and cutting for the outer profile of the parts and the M logo

5- speed is 13 mm/s and 80 % are the speed and power of the cutting process (black color). The scanning process ( Red color) has been conducted at a speed is 300 mm/s and power is 30 %. The M logo cut at speed 100 and power 80%.

6- The Morn MT3050D CO2 Laser Cutter

has been used for fabrication in the lab.

3D Printing

In the lab, the final sliced design of the arm parts and three coupling on Ultimaker Cura has been verified by the lab specialist. After the G code has been transferred from my laptop to the printer SD card.

The fabrication process steps are as the following ( as show in vedio):

1- The SD card has been inserted into the Prusa mk2 3D printer.

2- The holder g code file has been selected and the printing process has been started.

3- I used the black filament to print the parts

4- I am waited until the printer prints the first 5 layers to ensure that the printing process goes well.

5- I waited till the printer finish the printing of the parts, which was around 22 min for each coupling, and 3 hours and 57 mins for the arm.

6- After the part has been printed, I turned off the printer and cleaned the workplace.

7- Finally, I remove any extra materials, and parts now are ready to use.

Electronic components:

1-Arduino UNO

Arduino UNO is a low-cost, flexible, and easy-to-use programmable open-source microcontroller board that can be integrated into a variety of electronic projects. This board can be interfaced with other Arduino boards, Arduino shields, Raspberry Pi boards and can control relays, LEDs, servos, and motors as an output.

2- Stepper Motor (NEMA 17 )

Stepper motors are great when positioning accuracy is required such as CNC applications. This is a good quality stepper motor, NEMA 17 Standard with torque of 4.2 KG.cm

3- A4988 Stepper Motor Driver

Stepper motor driver Allegro’s A4988 DMOS Micro-stepping Driver with adjustable current limiting, overcurrent and overtemperature protection, and five different microstep resolutions (down to 1/16-step).

4-Extension Control Board for Stepper Motor Drivers (A4988 - DRV8825)

5- LCD Module 16 char.x2 lines

A Liquid Crystal Display (LCD) is a form of visual display used in electronic devices, in which a layer of a liquid crystal is sandwiched between two transparent electrodes.

LCD module connection with Arduino tutorial can find here.

6- Serial Bluetooth Module (HC-05 module)

This serial Bluetooth module can work as either master or slave. The HC-05 module for controlling Arduino via Bluetooth communication.

In this Tutorial, you can find we how to use the HC-05 module with Arduino via Bluetooth communication

7- 9V DC Adapter

The adaptor converts AC power to 9-volt DC for powering most electronic devices

8- Breadboard

A breadboard allows for easy and quick creation of temporary electronic circuits or to carry out experiments with circuit design. Breadboards enable developers to easily connect components or wires thanks to the rows and columns of internally connected spring clips underneath the perforated plastic enclosure.

9- DC Jack to terminal block converter

10- Jumper Wires (Male-Male)

11 - Crocodile Wires

software:

• Arduino IDE 1.8.19: is open-source Arduino Software (IDE) that makes it easy to write code and upload it to the Arduino board. This software can be used with any Arduino board, in this assignment, I use Arduino UNO.

You can find Arduino IDE tutorial for beginners here.

• Arduino Bluetooth Control: is an application that allows us to control the Arduino board via Bluetooth.

Arduino Bluetooth Control tutorial can find here.

Design and implementation of the Circuit :

1- Start by adding the power supply and 9v power supply to my design.

2- Adding the output action components ( stepper motors and LCD ) to the breadboard.

3- Adding the output control components ( A4988 Stepper Motor Driver ) to the circuit.

4- Adding the input components ( Serial Bluetooth Module (HC-05 module)) to the circuit.

5- Add the Arduino UNO

6- Adding connections between the components, as shown in the Figure.

In this project, the Wall Adapter Fixed 9V 2A DC for powering most electronic devices , and the Arduino UNO

The driver requires a logic supply voltage (3 – 5.5 V) and a motor supply voltage (8 – 35 )V. It can deliver up to approximately 1 A per phase without a heat sink , and 2 A per coil with heat sink.

1- Building the drawing arms and plate

To assemble the pivoting arms, an M3 bolt has been passed through the corresponding holes of the two arm pieces and fasten it with a bolt.

2- Mounting the Stepper Motors

Once the arms are joined, the stepper motors have been mounted onto the stepper motor plate using M3 bolts and coupling. Next, the circular pieces have been attached to the shafts of the two stepper motors. Also, the drawing plate has been attached to the third stepper motor.

3- Connecting the Arms and Stepper Motors

Once the stepper motors are mounted to the panel and the circular pieces are attached to the shafts of both motors, a bolt has been passed through the hole on the circular piece and secure it with a nut. the same process has been Repeated for three motors.

The bolts should not be fastened too tight or too loose.

4- Mounting the Electronics and Wiring

Once the box of body and arm is assembled you can mount the Arduino Uno board onto the panel using 4 M3 nuts and bolts. Next, mount the motor drivers on the Arduino Uno.

Finally, a power source of 9V has been connected to the + and - terminals of the circuit.

5- Mounting the Pen

The hole ( at the end of the arm) has been made large enough to hold a regular pen. To secure it firmly to the arm, we used M 3 bolt.

6- Uploading the Code

7- Testing and Results

To use the robot for pattern making, the pen has been held off the paper when the machine starts, and once the steppers are spinning, the pen should be placed onto the paper to avoid any sort of spillage and blotches.

Each pattern takes approximately 3-5 minutes to complete. Once you are satisfied with the result, gently raise the pen off the paper and switch off the machine.

I faced a big challenge during the design and implementation enclosure of the robot. The first enclosure had a lot of mistakes in the dimensions, the outer dimensions were larger than the laser cut machine workspace, also, there were many errors in the positions of the slots, all of this led to the failure of the first enclosure.

the solution, I back to fusion 260 and make redesigned for all parts, and this time I made assembly for all parts to ensure that every part fit together. Finally, I have had success finishing the enclosure successfully.

In the future, the DOPABOT will be powered by a Raspberry Pi 3, which will run a rather sophisticated algorithm to generate a vector image that results in a recognizable image of the subject.