Simple Bots: Walker

My goal with Walker Bot was to make a 4-legged walking bot that could be made in ten minutes. This bot ultimately took me three hours to make. That said, my goal wasn't to make one in ten minutes, but to make one that could be made in ten minutes. I am pretty confident that now that I know what I am doing, should I need to make a second one, I could do it in ten minutes. At the very least, you will be hard-pressed to make a simpler walking bot than this one. I would consider this project a glowing success.

Step 1: Go get stuff

You will need:

(x2) servos modified for direct drive**
(x1) telephone handset
(x1) 4 x AA battery holder
(x1) DPDT lever switch
(x2) CDs
(x2) 6" bolts
(x2) 5" bolts
(x4) bolts
(x4) bolt covers
(x2) thin 1" nut and bolt
(x1) a couple dozen assorted zip ties
(x1) print template (download below)

**Modify your servos for direct drive here

Comments

[mArtiAnOk]

does the CD toggles the lever switch?

[randofo]

Yes

[jvega7]

thank you for join it, now i am motivated for build it..

[mahsa arian]

its so amazing
i follow your great idea. thanks for share it :-)

[rohit007]

awesome man...!!...it really..wrked..nd dat too on my first try..thnx..i ll remeber dis bot....forever !!

[shivam dehinwal]

hey ! its shivam from delhi and i am also trying to make this one........but i cant find the servo motors as well as the DPDT lever switch........can u tell me from where did you find it?????????

[simplebotics]

i got one from an old rc toy. hope this helps and goodluck!

[dannystaple]

You will find servo's on ebay fairly regularly now - but old RC toys are also a good source.

[chaitanyak]

elegant mechanism :)

[superstatic27]

I'm a bit confused. So because it's a DPDT switch wired to run backwards also, you don't use the switch to turn it off but to reverse the motion? Would the only way to turn it off be to take the batteries out?

[randofo]

Yes. The only way to turn it off is to remove the batteries.

The DPDT switch reverses the polarity of the power going to the motor. When the polarity is oriented one way (+ to -) the motor spins in one direction. When it is reversed (- to +) the motor spins in an opposite direction. The bot is basically changing its own motor direction.

[mraghib]

Nice & innovative idea!Can you please tell me can we use toy motors instead of servos as they are expensive! Thank You!

[randofo]

Yes. Just get 2 identical geared motors.

[mraghib]

Is a toy motor and gear motor the same? Sorry I'm new to robotics!

[SCIENCEPAL]

Nice work dude! Its pretty cool!

[mistu99]

can u reply quickly because i need 4 Wednesday

[mistu99]

can i use a motor to replace the servo because in uae i can't find it

[jualone]

very weel

[sofsof]

that is so cooooooooooooooooool
i like it very muuuuuuuuuuuuuuch

[anubhavtalukdar007]

Continue giving us more instructables...........

[randofo]

Soon. Very soon.

[ptrinidad]

very good man!!!

[sajee]

my servo has 3 wires and how can i convert them into 2 wires like seen in the pictures

[robotics_sk]

hi, does it matter if instead of a standard servo we used a continuos rotation one?

[randofo]

That should be fine.

[robotics_sk]

how do i print the templates?

[randofo]

You should be able to open the eps with one of the image viewing programs on your computer. Then, just print it out using a normal computer printer (be careful not to re-size it)

[robotics_sk]

where can we buy the servos motors??

[randofo]

I'm using Parallax motors. Try:

Parallax.com
Jameco.com
Mouser.com
Digikey.com

[101nemesis]

the thing is if we modify the servos for direct drive.
wont it block the handle of the telephone.?

[randofo]

What do you mean?

[101nemesis]

no what i mean is ..
wont the bolts get hit by the arm of the telephone..
and could u pls tell me how does a modified servo work ..
as in how does it rotate exactly
thnk u

[randofo]

No, because the switch reverses the movement of the motor before it gets the chance to go that far.

Basically, a servo is a geared motor with a controller board inside. When I modify it, I remove the controller board so that the motor becomes direct drive. In the materials step, I have a link to how to do this.

[101nemesis]

thanks a lot for your help..
can u pass me the link cause i tried modifying and it was a great flop...
cheers

[Bj14]

Which type of servo motors are used here?
Can we use simple dc motors used in DVD,VCDs ?

[shivam dehinwal]

u can use the one found in the air conditioners..............you can it from an A/C service centre.........hope this helps.......

[simplebotics]

i was wondering could i glue two SPDT lever switches together and that means it will have 6 total leads and the cd can still press switch both ways? PLEASE HELP! thanks :) !

[randofo]

Yes, but it won't be as reliable. You would to carefully position them so they are both hit at once or you might risk shorting the circuit frequently. You should try to get a DPDT switch

[simplebotics]

ill just go with the DPDT switch, btw can i get them at radio shack? thanks :) !

[randofo]

You should be able to at most Radioshacks.