2 Servo




Servo 101


Other Robotic


Humanoid robotics gets their name from the fact that the robots walk (or aim to walk) like humans. For the most part humanoid robots fit inside the Bi-Pededal (bi-ped) robotics category, where a robot walks 0n two legs.

This will be a works in-progress web page where I will present the various results I have learned about making robots walk. I will be discussing walking and programming strategies that I have found to work, and what other people have discovered. My main goal is to help other people to get up to speed in learning how to make a machine walk.

Many of the discussions presented here will reference various robotics contests. The reason for this, is that robotic contests provide a motivating goal for the robot to accomplish. When other robots are competing in the same contest, you will have some sort of a measure to see how well your development efforts are progressing.

My initial robotics work was focused on the mechanical aspect of the robot since I like to make machines move (see Hardware Development). But when I discovered the humanoid robot kit from Lynxmotion I couldn't pass it up. What sold me on this kit were the servo brackets. They were expandable to just about what ever I could imagine. Since I needed to develop the software to make a robot walk, I decided to use this robot as my basic platform for my software development efforts (see Software Development).

To the left is my robot named Foo. For you software people, you understand what the name foo means. This is a 19 DOF (degree of freedom) robot. Each leg has 5 servos, and each arm has 4 servos, and the head has a single servo. Each servo is a Hitec 5645 digital servo (see Servo 101 for more information on servos).

This robot is using the Lynxmotion SSC-32 servo controller to control all the servos. This is very powerful servo controller that is inexpensive, and easy to use. And it has made the learning how to make a robot walk much easier.

The brain for this robot is a Basic Stamp 2p from Parallax. People keep telling me that you can't use a Stamp for these types of robots. I keep proving them wrong. Yeah, a CRAY supercomputer can make a robot walk, but so can a Basic Stamp. It all depends on what you know how to use. I like Stamps, and Stamps work. I believe in the KISS rule, Keep It Simple Stupid.

The photos here show some closeup views of the robot so you can see how it works.

I will be adding more information about this robot from time to time, such as software, schematic drawings, videos, etc.

This robot's name is Ed-209. It is a copy of the famous robot named Ed-209 from the movie Robo Cop. Ed-209 is my personal favorite movie robot, so I asked Lynxmotion if they could do a custom body design for me, and here is it.

This robot is all legs. Each leg has 6 servos. A 5 servo leg requires the use of friction and slippage on the ground based on relative feet movement for turning. Like what is used in Foo. Adding a sixth servo, enables the legs to rotate outward like our human legs can which gives greater walking mobility.

Again I am using a SSC-32 servo controller to control all the servos, and a Basic Stamp 2p for the microcontroller. Instead of a simple hand wired circuit board, I am using the Lynxmotion Mini ABB Board to interface the Basic Stamp with the SSC-32.