Let's Make Robots!

Quadpod Robot

Rasoul's picture
Cost to build: 
$98
Time to build: 
25 hours
AttachmentSize
quadpod.pdf23.55 KB

This is my first experience in legged robots. By making this quadpod robot I wanted to learn how to implement different gaits using servos. I used the same PCB designed for the other project, R/C little-buggy. I am attaching the circuit schematic which has the same micro-controller design as the other porject. Each leg has two degrees of freedom (DOF). I used micro servos (1.7 Kg.cm) and the result is good. However, it could be better if servos were a little stronger.

The controller board Schematic is attached as "quadpod.pdf". I had to change some components and modify the reset circuit of micro controller, though. These changes are not shown in the current version of schematic. Like the project R/C little-buggy, I programmed the robot with CodeVision AVR.

In the video, the robot takes its first steps according to the fastest gait I managed to figure out. :)

Comment viewing options

Select your preferred way to display the comments and click "Save settings" to activate your changes.
lumi's picture

I love your little bot. I also did one with cheap servos and it runs well with it....ok, one servo is broken now but that's acceptable when I see how he was treated during his presentations ;-)

Rasoul's picture

I like your little quadpod built with the same number of micro servos, too. Unfortunately I couldn't spend much time and effort to make it as perfect as I planned for at the beginning.

I will follow your little quadpod upgrades :)

lumi's picture

Yep, the same here. I still want to improve the walking, put more sensors on him, program more different behavior but the time to do that all is just not enough. Now I have to replace one servo because Chopstick Junior will go to the next photo shooting next Saturday ;-)

MoX's picture

I like your robot, and the way it walk :)

I built mine with standards servos but I think that 4Kg.cm is a minimum torque for quadruped (depending of the structure).

If you are interesting I posted videos in those we can see the consume under 6 volts :)

Have fun with your quadruped :) it's a very fun experience !

MoX

Rasoul's picture

I saw your quadruped robot's videos. I think your work is so cool! Your robot has 3DOF per each leg which lets you generate more complicated gaits than mine which has only 2DOF.

The servos I used are not strong enough but I think for the first experience they were good choice. Another problem that I am facing is to manage driving 8 servos by Atmega8. I use a timer interrupted based algorithm to control servos according to the desired gait and at the same time in the main loop of the program I would like to add more features like obstacle avoidance and so forth.

... And as you mentioned, it is really FUN! :)

MoX's picture

Hi Rasoul

the evolution of my robot , will be to use some sensor too :)

I think that I'm going to use an ultrasound sensor for the beginning, and as my quadruped walk slowly, the time for the reading of the sensor, the program processing , and a communication with a UART between a SSC32 servo's control (from Lynxmotion 40€) and a Uadruino Uno; could be faster enough to be reactive... i hope :)

Have fun with your robot !

MoX

hardmouse's picture

Simply give it a shell. It's cute~

Rasoul's picture

Thanks! :) After it took its first steps, it seemed to me that I could add some shell to make it like an animal!

ignoblegnome's picture

Cute. Very squeaky servos!

Rasoul's picture

Thanks! You are right! They are squeaky. Actually this is my first experience with a legged robot and I just wanted to play with a lot of servos to generate different gaits. So I bought the cheapest micro-servos. But for the future projects like this, I would purchase stronger and better servos. :)