A humanoid robot is a robot with its overall appearance based on that of the human body.The size of the robot and its functionality mainly depends on the DOF (degree of Freedom) and as well as type of servos.
1.Based on the DOF, how the size varies...?
A. DOF means the ability of robot to move in respective directions.
-->if you want to move your leg along X-axis say front and back, you require 1 servo means 1 degree of freedom .
-->similar way, if you want to move your leg along X-axis say front and back, and Y-axis say left and right you require 2 servo means 2 degree of freedom . So, for 2 legs the robot can be designed to make 4 DOF, similarly each part will be designed according to your requirement.
2.Based on the servos, how the size varies...?
A. The servo motors we can find were, micro servos with plastic gear unit and metal gear servos which are different in size when compare to micro servos please see these links below
2.Metal gear servos--->https://www.google.co.in/search?biw=1366&bih=659&t...
Now how to choose the servo
-->if your robot doesn't need to make any hard movements and the chassis were made up of some kind of fiber / plastic/ any light weight material then, micro servos were enough to make your robot to move. like small bi-ped robots
if your robot does need to make hard movements and the chassis were made up of some kind of metal sheet/aluminum/ any moderate weight material then, micro servos were not enough to make your robot to move.There we need metal gear servos.
Step 1: What You Need..?
Follow these steps:
1.Making robot chassis / body.
The above structure is a small humanoid robot and you can get the 3d printable files form the given below link. https://www.thingiverse.com/thing:356398
options we can have
1.Arduino +16servo controller (you can make your own or buy from any online store)
2.Raspberry pi +16servo controller (you can make your own or buy)
3.A dedicated servo controller like this.. http://www.robotshop.com/letsmakerobots/32-servo-...
4.Serial communication based servo controllers, you can find in many online store.
But My choice is
"3.A dedicated servo controller like this.. http://www.robotshop.com/letsmakerobots/32-servo-...
Because the above board has the following Advantages:
3.easy to interface
4.capability drive up to 32 servos individually
5.software interface will be much easy.... and many
3.Controller and servos / hardware /Software interfacing / entire tutorial.
(Feel free to post your doubts)
For the complete hardware and interfacing or any kind of help please go through the given link below. https://www.instructables.com/id/32-Channel-Seria...
If you think, it is hard to go through all those above links, you can buy directly the kit from the link given below. (for Indian people only), or you can directly search in ebay. https://www.instructables.com/id/32-Channel-Seria...
I'm also working on it, once everything was done, i will upload the video.
Step 2: 3D-Printer
Luckily we have ultimaker 3d printer, you can find the working of such 3d printer in the below link
You can use the files(https://www.thingiverse.com/thing:356398) in the above step... to get the 3d model of your robot