Things used in this project

Hardware components:
Ard nano
Arduino Nano R3
Gus 1719
C.H.I.P. Approved 3.7 V LiPo Battery
500 mAh battery
Dsc 0965
MyOctopus I2C TMP007 breakout module Infrared Sensor
HC-05 Bluetooth module
HC-06 Bluetooth module
HC-SR04 Ultrasonic module
Buy one that also works on 3.3V if you plan to use Lipo battery without step up converter.
Dot matrix display MAX7219
This display takes a lot of space inside Otto and leaves little space for battery so if you have larger battery or don't want animated mouth you can skip this part
This is optional, if you want nose that changes colour.
Touch sensor
This still needs to be tested for changing modes.
Arduino NANO Shield I/O
Adafruit industries ada260 image 90px
USB-A to Mini-USB Cable
Micro servo MG90
Adafruit industries ada1536 image
266 04
Female/Female Jumper Wires
8x8mm Micro Switch Self lock On/Off
 dsc1102 900x600
DFRobot Romeo Ble
as an option to replace the arduino and the shield
Otto DIY electronic kit
Software apps and online services:
Ide web
Arduino IDE
Ide web
Arduino Web Editor
D94d qxu
Autodesk Fusion 360
Visuino - Graphical Development Environment for Arduino
Hand tools and fabrication machines:
3D Printer (generic)
09507 01
Soldering iron (generic)
Phillips Cross screwdriver
Hy gluegun
Hot glue gun (generic)

Custom parts and enclosures

Thingiverse files
Now we have space for switch and buzzer, new legs
You can modify the size, use the parts for 3d printing and add parts as desire


Basic parts shematic
Please note that was made in Autodesk Circuit the ultrasound lack of one cable,


Function that reads voltage of batteryArduino
//Function that reads voltage of battery

#define BAT_MAX  600 //max battery voltage in mV/10
#define BAT_MIN 400 // min battery voltage in mV/10
#define SLOPE 100/(BAT_MAX - BAT_MIN)
#define OFFSET  (100*BAT_MIN)/(BAT_MAX - BAT_MIN)

this you add in shetch where zowi reads batt voltage:

    batt = ((readVcc() / 10) * SLOPE) - OFFSET;
    if(batt>100){batt = 100;}
long readVcc() {
  // Read 1.1V reference against AVcc
  // set the reference to Vcc and the measurement to the internal 1.1V reference
  ADMUX = _BV(REFS0) | _BV(MUX3) | _BV(MUX2) | _BV(MUX1);
  delay(2); // Wait for Vref to settle
  ADCSRA |= _BV(ADSC); // Start conversion
  while (bit_is_set(ADCSRA, ADSC)); // measuring

  uint8_t low  = ADCL; // must read ADCL first - it then locks ADCH
  uint8_t high = ADCH; // unlocks both

  long result = (high << 8) | low;

  result = 1125300L / result; // Calculate Vcc (in mV); 1125300 = 1.1*1023*1000
  return result; // Vcc in millivolts
Avoid obstacles
Basic code to avoid obstacles, also include all libraries and is easy to modify for custom moves


Yo2 r1nyp5pmbe
Camilo Parra Palacio

Toy Maker & Industrial designer working in China, design inflatables and pool accessories, in my spare time make robots and ride bicycle

Davor Levstek

Working as quality control inspector at rail vehicles factory. I'm interested in programming microcontrollers, making toys and learning about everything.

Gus 002
Gustavo Reynaga

Iam a teacher

Img 20160724 145732 vliseurtj2
Frank Lopez

Humanoid Android Engineer & Designer im also a MAKER and Currently building an A.I based Neural Network for a Android and other prototypes.

Jason Snow

Industrial Electrician, PLC programmer and Electronic designer

Pablo E. García Palacios

Computer Engineer and Robotics Teacher in Spain.

13962535 10207402354274165 6730633353067878632 n
Liao Ping Lun

Software developer in Yunlin County, Taiwan. Motto: Smart Work, Work Smart. Enjoy it. About me:



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