Introduction: Make a Simple Bipedal Humanoid Robot (Servo Walking Robot)

Picture of Make a Simple Bipedal Humanoid Robot (Servo Walking Robot)

Bipeds are really cool because they are by far the most recognizable kind of robot. Companies have spent decades and millions to make these things. I've been wanting to make a bipedal bot for sometime now but most of them need a lot of motors and are pretty expensive to make.
I managed to make a simple bipedal robot at home out of essentially four micro servo motors (which are pretty cheap), an arduino and a breadboard. The bot can walk, kick, dance, navigate slopes etc.
Moreover since it's an arduino you can always add sensors or other body parts pretty easily and experiment with the bot.

Step 1: What You Need:

Picture of What You Need:

1) Micro Servo's (4 nos) :
2) Arduino (1 nos) : I used an UNO R3 but anything works
3) Mini Breadboard
4) Wires, Glue, Epoxy/Sugru/Clay/Hot-Glue-Gun.
5) Bits of cardboard

Yup. That's all you need to start. :)

Step 2: Attach Motors Together:

Picture of Attach Motors Together:

Use your epoxy/Hot-Glue/Sugru to attach two motors perpendicular to each other as shown in the pictures. Make two sets of these. Each set forms a leg. Glue the two legs together. I used a broken piece of plastic to ensure that the legs are glued flat and aren't angled with each other.

Step 3: Wiring!

Picture of Wiring!

Now connect the for motors on the breadboard. The last pin in each motor wire is brown signifying NEGATIVE. On the breadboard connect all the left side pins to one common negative pin. Similarly connect all the middle pins to one common POSITIVE pin. These common pins are now connected to the Gnd (for Negative) and +5V (for positive) respectively. The first pin goes into the PWM pins of the arduino. If you've used servo's with an arduino before you'll find this step awfully simple to understand. If you've never used arduino's and servo's before I recommend you view the following link to better understand how they work.

Step 4: Assembly:

Picture of Assembly:

Now attach a piece of cardboard to the top of the legs and mount the arduino and breadboard on to it. Your robot should begin resembling a body with legs now. Wrap any excess wiring that may be present with tape into the robot. Hanging wires disrupt the robots balance while walking.

Step 5: Feet and Balance:

Picture of Feet and Balance:

Take two square pieces of card and stick them to the bottom of the legs to give the bot bigger feet and better balance. I used clay to make the join look neater.
Structurally your bot is now complete!

Step 6: Programming:

Picture of Programming:

Programming is the hardest part of this bot but I have a few programs that I've already managed to get working with this bot. Load them onto the robot and watch it do wonders!
Once you're done loading a program onto the bot you can use a USB-Wall pug (Like those that come with modern smartphones) to run the bot directly off the grid. Although in this configuration the power wire can occasionally disturb the bots balance making with wobble while walking.

Step 7: ENJOY!

Your bot is done. Remember that this isn't the end. The above set up is very simple so you can always add to it.
Two motors on the side can make arms and complete a humanoid. Moreover you can easily add sensors to the bot and make it do different stuff. For example, by adding a tiny LDR and a servo controlled pen refill I made the bot protect a car. It fired a projectile if anything came in the way. Have a look at the video.

(Too see how to add an LDR to an arduino : )
Hope you liked the instructable. Feel free to comment below. :)


MikkelO (author)2017-05-07

Fun little project, with nice and easy instructions. Thanks for sharing.

I have a small video of the one i made:

MilinP2 (author)2017-03-26

my servo motor first goes to the refence position and then takes all the turns

and i want to stop this direct he movemen tit should take which i progrmmed.

MelodyB18 made it! (author)2016-06-09

Great tutorial, it worked like a charm :)

MilinP2 (author)MelodyB182017-03-26

hello i have a question that even i tried to make a bot like this and now my servos refernce position are not alligned properlly

i mean it does not goes near to thAT otherwise it will break the potetniometer inside

SamsonT4 (author)MelodyB182016-10-18

he sketch isn't working for me I get this error "redefinition of 'Servo rightfoot'"

Did you alter anything if so please let me know I really want to try this project.

If not could you please provide a copy of your sketch.

lady09 (author)SamsonT42016-12-14


MelodyB18 (author)SamsonT42016-10-18

I followed the instructions to a T, and then added a battery, a pair of googly eyes, and a blue LED light that was a separate circuit. The main problem I ran into when building it was not having my ground set up properly--It's been long enough that I forget exactly where I went wrong, but I messed around with it for a while and got it working. I've attached a picture of the circuit diagram I made, the LED light is connected to port 13 and GND, so you can ignore that part. I no longer have the sketch, but I'm very sure I didn't change the code, so I don't think that should be the problem. I'm still new to Arduino myself, so I'm afraid I won't be much help beyond this :) If it still doesn't work for you, you could try sending me the sketch and I will try it on my robot.

Darthvader20 (author)MelodyB182016-06-17


李白 (author)2015-09-30

How to write the code to burn in, please

Rohith 1234 (author)李白2016-12-23

Download the codes in your PC and open it in the arduino app in your pc. Then click upload

Jordansanj (author)Rohith 1234 2017-01-30

Im sorry..... i got the codes
Should i use netbeans to upload ?

Jordansanj (author)Rohith 1234 2017-01-30

Where are the codes?
Please give me ........ ??

priyav21 (author)2017-01-17

Great Project, planning to work on this. How much time does it take to build this project?

Rohith 1234 (author)2016-12-23

Great project

Joseph JoshuaP (author)2015-08-27

what battery should I use with this ?

It us not operated with battery

Bhanuprakash veramallu (author)2015-09-16

What model servo motors i should use

Servo any model i recommend sg90 tower pro micro servos

lady09 made it! (author)2016-12-14

i love 2ne1

JibinC (author)2016-11-17

Can I use the big bread board

murushirago12 (author)2016-11-02

i made the balance and the wirings ... (arduino has the codes already) but my biped start walking coockooo .... is it the servo motor ?

or my wiring .... i cant really figure if you are refering to righthigh means the top servo

Saiyam (author)2015-04-16

Very well done. But wouldn't it be better if you used a battery instead of a plug pack.

sidgupta (author)Saiyam2015-04-16

Yeah. You can. I've done it myself. I think I've forgotten to put a picture. Thing is you have to use three thin 3V button cells to run the robot because a big 9V battery tends to cause balancing problems.

SamsonT4 (author)sidgupta2016-10-18

The sketch isn't working for me I get this error "redefinition of 'Servo rightfoot'" and "redefinition of 'int pos'"

This is a great project but I cant make it work. Please help me.

sarower hossain (author)sidgupta2015-11-29

Bro, can u give me the circuit diagram?

SamsonT4 (author)2016-10-18

the sketch isn't working for me I get this error "redefinition of 'Servo rightfoot'"

murushirago12 (author)2016-10-12

sir ... im trying to do the biped using only two micros XD would it be possible ?

I watched your demo... and I analyse the sequence of the bot .. would it be working the same by only using two micros ??

MAHFUJ SHIKDER (author)2016-10-01

How much cost for this project?

Prakash agarwal (author)2016-08-04

My robot can't make balance

Prakash agarwal (author)2016-08-04

My rovmbot can't make balance

harshc1 (author)2015-10-04

and how to control to robot please tell...............................


Sankeerth San (author)2015-12-31

Can i use sg90 servo ?????
I am new to arduino.

just as an info:micro servo sg90 servo is pretty much the same and work the same way.this is not arduino stuffs it's a very diffrent branch of electronics

Prakash agarwal (author)2016-07-25

Can I use servo with hi torque instead of using micro servo

Venkat Jayanth (author)2016-06-27

I want to add bluetooth hc05 and ultrasonic sensor sr04 to this. But is the circuit. Can u please help me. Please.

dev5 (author)2016-06-05

Ok what is with this glue?i cant find any.nd d glues u mentioned are very any other way?

SuyashB2 (author)2016-05-28

can u help me to choose motor shield in running twelve to sixteen servo motors for making a humanoid robot

YUSUF6731 (author)2016-02-26

hii in 2nd year mechanical engg. I interested in arduino projects making,but these terms are new for me. I have uno R3. Can you make full tutorial video of your bipedal robot???

Elecrow (author)2016-01-29

Fantastic project!

tharuntamil (author)2016-01-20

how arduino is standing on it glued?

AnirudhT1 (author)2016-01-14

Can you please make an instructable for an autonomous version of this?

SKYuvraj (author)2015-12-11

One of My Favorite Instructable on Instructables.
Thank you for sharing.

RohanS23 (author)2015-11-14

I am not finding the HXT900. Can I use the tower pro micro servos

Espasio (author)2015-11-03

Где схема подключения?

李白 (author)2015-10-08

Steering gear was stuck what should I do

harshc1 (author)2015-10-04

can you tell how much power dose it need to work so that i can use some other source of power

ShivK4 (author)2015-10-02

How can i get the program for this??
N how to install?

ShivK4 (author)2015-10-02

Sir ,
how can i get the program for this project??
Can u plz eplain about the installation of program?

Artixvon01 (author)2015-07-04

Sir, I try to build your biped but things running out of control. When I uploaded the program, the legs are rotating in different ways.
I will appreciate any help. Thank you.
My micro servo is only 60 deg.
I'm new in electronics.

About This Instructable




Bio: Love simple robotics, electronics, sensors, arduino projects and generally building, modifying and opening up stuff
Add instructable to: