Let's Make Robots!

pivot point

Hi, I would like to make a pivot joint like in the knee or elbow. I would like to control the angle by high torque Ac motor. How do I construct the joint and the gear? How do I make only one tube to move while the other tube stays in its position? I attach a picture that will demonstrate what I thought to be the basis for the joint. Thanks guys

Motion controlled robot with arduino and kinect sensor

 I am new at coding. I have to do motion conrolled robot with kinect sensor and arduino for my final year project. I have 9 servos for my robot. It follows my motions. **For example;** if i move my arm, it moves its. When i move my leg, it moves its. Where do i start ? Is there any examples for this project ? Is there any examples for codes ? Sorry for my bad english and thank you for your replies. 

PWM on High Current(amp) Actuators

I'm trying to move up into the category I originally got into robotics for in the first place: bigger buddies!

I have a Raspberry Pi I'd like to use to control some linear actuators, which are 12v and lift about 225lbs. I'm unaware of their amp usage: a search for similar rated ones said ~4-5A. They were purchased from an online auto parts place, so it's unlikely they'd know.

Help with wheel rotation sensing

Hi guys!

Im new to this forum and I am hoping to get a little help with a problem I am trying to solve. I have a small differential drive robot that I want to be able to push through a course and have it record wheel spins to then retrace the exact same path. The goal is to have the robot follow the recorded path and return to the origin point.

Batteries Got Exhausted in Few Seconds

I am building myself a simple robot car.

Simply, an A10 Olinuxino board  (my first false start because of the hard work of interfacing the ultrasmall 0.05'' pins header) interfaced with a Pololu Dual Motor Driver (https://www.pololu.com/product/2130)

To move forward, backward, left an right, I use a simple Web Interface which sends Ajax commands to a Python Web Server I wrote.

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Wiper Servo and H bridge woes

Hello All. I have an engine test cell / dyno that I operate the throttle control with a wiper servo.  I set it all up and use a robot power simple H bridge. It works OK.  But recently it the H bridge went to ground.  I think we left the power on all day and stuffed one of the power transistors!

Geared motor driven robot

Hi everyone. I need some help in designing a microcontroller based program (preferrably Arduino) that controls the motion of a geared motor driven robot.


Please help.

Help with Selection of Motor AC or DC


    I have a bit of knowledge about electronics but learning more while working on this project.

   I am working on a project where I am designing a electronic deivce (close to a robot), which can be used for working on agricultural fields. The size of the device is planned to be 30cm width and 30cm of length. The device that I am planning to make is much closer to the image in the following link :