Evil Mad EggBot User manual

EggBot Instructions

The eggbot is a mini cnc machine capable of drawing on spherical
objects such as eggs or christmas decorations balls.
Users can produce their own digital drawings and the machine will
then transfer them onto spherical objects.

EQUIPMENT LIST
•3D printed parts for the
eggbot, available here
•3 x [M8x300 threaded rods]
•1 x [M8x100 threaded rod]
•2 x [608ZZ bearings]
•1 x [9g micro servo]
•1 x [spring, slightly larger
than 8mm in diameter,
about 4cm long]
•2 x [silicon o-rings]
•1 x [Arduino uno board]
•1 x [Adafruit motor shield V2]
•2 x [NEMA 17 stepper motors ,
step angle 1.8°, rated voltage 12V,
rated current 1.7A]
•1 x [Power supply 12v/2A]
•20 x [M8 nuts]
•1 x [M2x14 screw]
•5 x [M2x10 screws]
•3 x [M3x15 screws]
•3 x [M2x7 screws]
•5 x [M2x10 screws]
•3 x [m3x15 screws]
•3 x [M2x7 screws]
•2 x [M3 bolts]
•2 x [M3 washers]
•6 x [M2 washers]
•1 x [M2 nut]
•1x [M3x35 screw]

Assembling instructions

ATTACH THE BEARINGS
Position the bearings on each side part of the eggbot as depicted below

ASSEMBLE THE MAIN BODY
Assemble the two sides, the rear of the eggbot and the supports for the two
sides (purple 3D printed parts in the picture below) together, using threaded
rods and M8 bolts. You will need about 20 bolts, 1 M2x14 screw and 1 M2
nut to achieve this.
3D printed
side supports

MOUNT THE X AXIS MOTOR
Use 3 M2x7 screws and 1 M2x14 screw + 1 M2 washer to mount the X-axis
motor to the left side of the eggbot

MOUNT THE Y AXIS MOTOR
Use 4 M2x10 screws and 4 M3 washers to mount the Y-axis motor to the
back of the eggbot.

MOUNT ATTACHMENT PIECE FOR PEN ARM
Place 2 M2 nuts inside the 3D printed part depicted below. Then mount the
latter to the Y-axis engine (M2 nuts facing the rear of the eggbot).

ASSEMBLE PEN ARM
Use 2 M3x10 screws + 2 M3 washers to mount the part mentioned above to
the servo arm.

MOUNT THE PEN ARM
mount the arm for the pen to the Y-axis motor as shown below.

ASSEMBLE THE SUPPORT FOR THE SPHERICAL OBJECT
Attach the 3D printed head onto the X-axis motor.
Position the M8X10 threaded rod to act as the support on the right hand
side. The spring should be positioned on the inside of the structure along the
threaded rod. Attach the 3D printed head onto the end of the thread rod.
This should be able to move backwards a little bit by compressing the spring.
The egg should sit comfortaby between these two black 3D printed parts. A
firm grip should be made on the egg due to the slight compression of the
spring.

CONNECT STEPPER MOTORS
Connect the cables of each stepper motor to the motor shield. connect the
X-axis motor to M1 and M2 (left side of the motor shield) and the Y-axis
motor to M3 and M4 (right side of the shield).
Connect the cables in the same order for each motor. For
example red, blue, black and green from left to right, i.e. red
and blue on M1 and M3, black and green on M2 & M4.

CONNECT THE SERVO MOTOR
Connect the servo motor to “servo 1” on the shield, with the brown cable
(ground) on the left and the yellow cable (signal) to the right.

CONNECT THE POWER SUPPLY
Finally, connect the power supply to the power pins of the shield. Red to the
positive input (left) and black to the negative (right)

FINAL CHECKS
•The distance between the two sides should be around 16 cm apart
•The spring should be slightly compressed when the egg sits inside to
hold it sufficiently
•The egg is being held firmly so that it won’t slip when it rotates
•All bolts are tightly done up
•Sides are at 90 degrees to the desk and straight
•The pen arm falls to the centre of the egg
Please tell Chloe you have finished so you can check that the program
on the board is working!

PROGRAM YOUR BOARD

INSTALL FIRMWARE
•Get the Arduino IDE from https://www.arduino.cc/en/Main/Software.
•Get the firmware from https://github.com/jinschoi/SphereBot
(download ZIP button)
Open up SphereBot.ino with the IDE.
a. Under Tools, ensure Board is set to “Arduino/Genuino Uno” and Port
is set to the proper serial port.
b. Under Sketch, Include Library, Manage Libraries…, search for adafruit
motor shield v2, and make sure it is installed.
Plug the USB cable to your hardware and upload the firmware using
the right arrow button.

CONNECT TO THE BOARD
Connect the board using the USB
Check that the correct board and port is selected

VERIFY IT WORKS
Click the serial monitor button in the upper right of the IDE.
Make sure you have “Newline” and "115200 baud” selected in the lower
right drop downs.