Otto Minion

This is my version of OttoDIY. I wanted to print Otto Minion and found the sourced one, but unfortunately it wouldn't work for me: my printer did not perform well with the provided stl, and did not have the necessary Arduino shield. So I decided to go and remix it from scratch using FreeCAD and Kicad. Basically I wanted to avoid supports so I splitted out arms holders from the main body and made a slot to snap them in later. In addition, I designed a custom shield for the Arduino and the rest of connectors, including a bluetooth breakout and ultrasonic sensor. As I only have an Arduino Pro Mini, connection to the host computer is made via FTDI pins. Accordingly, the head was designed to allow connection trhough this interface.

BOM:

1 x Arduino Pro Mini
6 x TowerPro-like SG90 mini servos
1 x HC-05 bluetooth module
1 x HC-SR04 ultrasonic module
2 x 3,7V 1,2ah AA size li-ion battery
1 x MT3608 step-up converter
1 x TP4065 battery charger module w/protection
1 x active buzzer
1 x push button mini switch on/off
2 x 1/4w carbon resistor (voltage divider for HC-05 Rx pin, as it's 3.3v only: 10k & 4,7k)
some pin strips, pin sockets, cables and dupont connectors.

A Kicad project is attached for the main shield, including schematics and PCB design. Most surely you will need to adapt it to your needs.

3D printed parts:

I only needed to redisign the head, main body, arms and hands. Legs and feet was printed using the original OttoDIY FreeCAD file from official site.

See pictures for arrangement of components. The main board depicted has an error (corrected in the Kicad pcb provided) as it has Tx and Rx swaped.

Have fun.

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