Based on a 6 DOF BRAT clone kit from ebay ($50!)
Uses 6 MG995 45g servos:
2 Ankle Servos, 2 Knee Servos, 2 Hip Servos
4xAA Nimh to drive servos
2xAA to drive Raspberry Pi via a cheap "emergency charger"
All controlled by a Raspberry Pi using servoblaster software PWM and programmed in python (but might move to C if I need the speed)
Still a bit wobbly as I'm not using the knee servos much at the moment.
Its interesting that I can get it to walk with just 4 servos in use - so there's an idea for my next bot ;)
[edit]
My 8 year old nephew Jake thought the bare robot looked boring,
so he drew paper clothes, and added arms and legs:
https://www.youtube.com/watch?v=5OQgIfOEktk
also now goes left/right by varying the individual leg's stride length.
I wrote some code for a fast kick:
https://www.youtube.com/watch?v=noObFbkCABU
This runs the knee/hip servos at full speed, instead of slow smoothly interpolated sweeps like used in walking/ leaning
E.g.
Servo.hip = 90
Servo.hip= 140
vs
For sweep in range (90, 140):
Servo.hip = sweep
time.sleep (0.01)
I've also moved the battery pack down to the hip for better stability and more torso movement, and can sit down after a long day:
http://www.youtube.com/watch?v=PEIbgrYKP0I
Next step is to give it some autonomous behaviour (HC-SR04 ultrasonic sensor and/or camera)
Walks and turns, kicks a ball, and sits down !
- Actuators / output devices: 6x MG995 servos
- Control method: WiFi
- CPU: Raspberry Pi
- Operating system: Raspbian
- Power source: 4xAA NiMH + 2AA NiMh
- Programming language: Python
- Target environment: indoor
This is a companion discussion topic for the original entry at https://community.robotshop.com/robots/show/wobbly-raspberry-pi-biped