Achtually in the project its not too much about creating hard ware. Also its not too much about electronics, that has not changed since the first project (bechele 1) because it consists of cheap ready made parts. At prices of about 4 euro for a PCA9685 PWM controller direct form china, self made simply does not make sense. However you need to know the used parts and how to wire up, therefore the description here:
The Hardware of the project consists of the following parts:
- Raspberry Pi 3 Modell B, Raspberry Pi 1B or OrangePi PC
- 16 channel PWM servo controller(s) from Duinofun, DeekRobot or Adafruit based on chip PCA9685
If you need more than one PCA9685 PWM PCB, see the following link how to use several: Servo Board Chaining
- Here you can find more about how to wire the recommended components: Project main wiring
- Analogue (or digital) model building servos – for example SG90, MG90 or many other types.
- Plug based power supplies 5V 1x for Rasperry Pi and 1x for each servo PCB (The partition of the power supplies prevents of electrical disturbance and is actually mandatory) You may also use a big 5V power supply for several PWM servo PCBs. But make sure each board has its own power line to the power supply. I noticed, that chaining the servo power through the Extension pins leads to problems with electric disturbances, that caused the PWM PCBs to work unreliable.
- The joy stick (self made) with data processing via Arduino Micro Pro and transfer via serial interface to the Raspberry Pi. Alternatively a USB joystick or gamepad may be used instead.
- The model, puppet or movement mechanics for your individual project. You may use your own design, parts of my eye mechanics designs on Thingiverse or any other mechanics, that may be driven by servos.
- Amplifier and loud speaker that amplifies the audio data from the Raspberry Pi. With Audio you are not bound to the audio jack. You may also use the HDMI output, or any other audio hardware USB or GPIO based you can add to the mini computer. Just set up you audio mixer in use (alsamixer) accordingly.
I recommend to use one of my 3D printable eye mechanics, since the time to build them is much less than making your own hand made mechanics.
3D printable eye mechanics on Thingiverse.com:
Short the functions of the puppet head(s):
- Movement of the eye lids left and right seperately (2 Servos)
- Mouth movement open and close (1 Servo)
- Eye movement left -right and up-down (3 Servos)
- Movement of the eye angle (1 Servo)
- Movement of the eye brows (2 Servos)
- Movement of the mouth corners (2 Servos)
Here some impressions of the two most recent projects: