Building humanoid robot diagram and materials

Community General Discussions
1

my plan is build a robot based in this project

https://www.robotshop.com/letsmakerobots/node/31960

but with one lipo 3s 5000mah that will feed all the system and a powerful brain, the udoo board

my list of materials

1xacelerometer 3axis and gyroscope 3axis sensor

1xultrasonic sensor

1x lipo 3s 5000mah 11,1v(it will feed ALL the system including the servos and the boards)

1x bec with output 5v 8A(it will convert 11,1v in 5 8A to feed the servos)

1xudoo board(quad core 1gb ram board with arduino due integrated)

1x logic conversor(comunication between UDOO arduino due(3,3v) and the servo controller(5v))

so what is uncertain...

1x ssc board controller up to 32 servos but i dont know what type(lynxmotion or torobot? lynxmotion you can put up to 30A,but torobot is compatible with usb(include bluetooth usb dongles) and ps2 controller)

1 x camera but i didnt choose what type and model, vga 640x480 is enough.

15-20 servos mg995(what can i do with 15?17?20 degrees of freedom?)

10-???-brackets,i dont know how many brackets i gonna use and what type.

4-???-cables to transform udoo in DC or conect it directly to the lipo 3s,same with the ssc 32 servos controller and the bec that will feed the servos

the udoo board ,ssc servo controller and the bec will be in parallel but what type of cable, can i use to do this?

in the lynxmotion controller board i can connect the servos and power up them with the pin specificaly designed to do it

however i dont know if i can do the same with the torobot servo controller(just plug the servos directly in the board and connect the power supply in the correct pins in the board)

here is the link to torobot http://www.elechouse.com/elechouse/index.php?main_page=product_info&cPath=&products_id=1883

and how much current the torobot can take.10A is a good number ,at least 8A.

i am asking because i didnt find any kind of information related about torobot and i need help in other areas.

thanks in advance!

2

i am excluding the BEC from

i am excluding the BEC from the list

i found a step down conversor with >90% efficiency

as wikipedia says about BECs:

There a more complicated switched-mode regulator should be used, as the BEC has to deal with losses. These losses are proportional to the difference of the target voltage of 5 volts and the voltage of the main battery; as well as they are proportional to the provided current. For example, take a 10-cell (NiMh) accumulator with a normal voltage of 12 volts. With a peak current of 5 A, the BEC will have losses of (12 V − 5 V) × 5 A = 35 W. With a linear regulator, these 35 W will be converted to heat and so require a large heat sink. In all cases, it is a good idea to mount some large capacitors to buffer the regulated output. In large plane or ship models, another possibility is to buffer the power supply with a further capacitor near the actuator’s (servos).

in my case


With 3S: (11.1V - 5V) * 8A = 48.8W of loss 
With 2S: (7.4V - 5V) * 8A = 19.2W of loss

With 3S: 64W + 48.8W = 112.8W total
With 2S: 64W + 19.2W = 83.2W total

With 3S: ~30 min
With 2S: ~30min

but this step down converter has >90% of efficiency

it converts 12v/24v to 5v 10A

http://www.current-logic.com/shop/index.php?main_page=product_info&products_id=8

there is a little observation

i will use 7,3 A and this step down conversor says:


“only use no more than 80% of max power if the converter is going to be working for more than 30 minutes continuosly”

80% of 10A is 8A,i will just use 7,3A what means that this conversor fits perfectly!

3

Welcome on LMR

I agree with Wise Dan, and I want my share of copyrigth henrq. :wink:

And I’m going to reinforce my previous sayings to you: just go with 2S.

4

Hi henrq! To give you some

Hi henrq! To give you some help, I would like to know what you intend to do with your humanoid. For example: you want a humanoid to fight, or to grab things, or just to walk around? Other thing: what is the purpose of a camera on this robot? Just for remote control and see where the robot is? Or to process images with OpenCV or something like this, to face detection or object tracking, for example?

I’m asking this because the answers can give you some way to go. For example: if you want to process images, something like the Raspberry Pi (or the UDOO that you have mentioned) will be necessary. But if you want to use a camera simple to see remotely where your robot is, just an Arduino board is what you need. And in this case I think Arduino (Mega) is better than servo controllers (just my opinion).

Other thing you got to consider is the cost of such a board like UDOO will be for us that live in Brazil.

About servo brackets: on eBay I found a nice kit for humanoid with a reasonable cost (http://www.ebay.com/itm/New-17DOF-Biped-Robot-Educational-Robot-Kit-Servo-Bracket-Ball-Bearing-Black-/271237534022?pt=LH_DefaultDomain_0&hash=item3f27045146), but I, personaly, prefer to make my own.

Take a look https://www.robotshop.com/letsmakerobots/node/32828 .

Other thing I would like to know: have you already tried something with Arduino?

5

face recongntion,voice

face recongntion,voice recognition, using of extensive neural network,fuzzy logic or genetic algorithm.


one important rule from robotics is that the system with more options control ALL the systems, the udoo board is more powerful than arduino and have more options in control and expansion slots. so control many systems because have more options

walk around and in the future have an hand to grab some objects(i saw these hands for robots and they appear very basic,not much functional)

i know the history of brazil-cost of living ,taxes,duties etc…

but even if i am obligated to pay taxes it will be cheap, in mercadolivre.com.br they sell things with twice the price even the triple of the prices that americans pay in ebay/amazon etc

 

i am working on it ,i am studying alone and i am choosing the pieces carefully

as soon as possible i gonna post the generic sketch of the robot

your post of homemade brackets is impressive! but where i can find polystirene here in brazil? the type that you bought is the expanded polystirene or high impact polystirene ? 

now i am interested in make my own pieces

i apreciate your help!

6

Well, if you are well

Well, if you are well decided, go ahead man!

I’m glad you liked my post. Making your own custom brackets is fun and this way can make specific parts to your project, that you can’t buy.

About the polystyrene: expanded polystyrene is something like styrofoam (isopor, in portuguese). The one I bought is high impact (here in Brazil we call PSAI). Here is the link for the one I bought: http://produto.mercadolivre.com.br/MLB-498881648-chapa-de-poliestireno-psai-branco-2mmx1000x2000mm-_JM . Very cheap!

If you’ll need some help with your brackets, contact me.

7

i am searching and studying

i am searching and studying three robots

robophilo(its movements with a simple servo)

darwin op (most because of its advanced features like object and voice recognition)

rq huno(its advanced movements like handstand,do a kick in the air)

i am impressed with rq huno moves ,darwin op hardware(he can recongnize a ball and play soccer , he has voice reconignition).

both rq huno and darwin op ,have an servo that can rotate 360 degrees

and my robot with servo mg995 and robophilo are capable of just 180 degrees

however with one little modification inside the servos resistors, i can rotate 360 degrees. but i must do it 20 times

i want to know what is necessary/what i need to do these movements in the video:

http://www.youtube.com/watch?v=bnzs80e3RzI

RQ huno is able to handstand,somersault, give a kick in the air and rotate in a way that the arm makes 90 degrees with the forearm.

what need i to adjust to achieve these movements?

do i need modify the servos from 180 degrees to 360 degrees or modify the brackets and make my own brackets like dickel suggested?

here is what robophilo is capable to do

http://www.youtube.com/watch?v=xOs0sPbBJLE

http://www.youtube.com/watch?v=3FYP5znF5KY

and what darwin op can do

http://www.youtube.com/watch?v=1WEgNQjL66g

thanks!