Featured on the cover of the Feb 1997 issue of Dr. Dobbs Journal

Last updated 12 November 1998

This page is always growing, please e-mail me if you have any suggestions and/or useful links.

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Roboty as of early August 1996 with the prototype sensor head turned to look into the camera. (Note 1 foot ruler in foreground for scale).

Some time ago I started a project to build a six-legged autonomous robot. The legs are controlled by a pair of RC aircraft servo-motors for each leg. Each servo-motor pair is controlled by a Motorola MC68HC705K1 processor. This CPU has 504 bytes of OTPROM, 32 bytes of RAM and 64 bits of EPROM, it has 10 I/O lines and fits in a 16 pin DIP. I programmed the processor to have two PWMs to control the motors, and to communicate with a supervisory CPU (originally over a nibble wide "bus", but now using SPI). All six controllers are daisy-chained together on the bus and have jumper settable bus addresses. The MC68HC705J1 is a similar, slightly larger controller.

The robot is built on a frame made of U-channel aluminum, and has 1/4" aluminum rods for the main part of the legs.

I have learned a lot about six-legged gaits (which turn out to be an un-natural motion for bipedal humans -- the book by Song and Waldron was a great help).

The thing seems to have started a life of its own:

* How do the different kinds of batteries perform ?

* I stumbled across this interesting demonstration, by Noel Rode (, of how the MIT robot Genghis walks (zipped binaries for DEC, SUN, SGI, Linux and DOS, 393Kb).

* Another view of Roboty next to ROCI

* The current status of Roboty

* A newspaper article on Roboty from the Monterey Herald (26 August 1996).

!!! I am building this machine from scratch using an Emco Unimat-3 mini-lathe/mill for the metal and plastic parts. If you are mechanically inclined you might want to take a look at the Personal CNC's home page

You should definitely also know about:

Small Parts Inc.
13980 N.W. 58th Court, P.O. Box 4650
Miami Lakes, FL 33014-0650
Voice: (800) 220-4242
Fax: (800) 423-9009

They are a great resource for mechanical parts, metal and plastic stock, etc. (I bought several parts that I use in roboty there, including the ball-joint "ankles" and teflon rods for bushings).


Robotics Literature

Here is a book that I have found to be VERY useful:

Song, S-M, and K.J. Waldron, 1989; Machines That Walk: The Adaptive Suspension Vehicle, MIT Press, Cambridge Mass, 314 pages, ISBN 0-262-19274-8

And if merely walking isn't challenging enough for you:

Raibert, M.H., 1986; Legged Robots That Balance, MIT Press, Cambridge Mass, 233 pages, ISBN 0-262-18117-7

And of course there is the modern classic (not much on walking robots, but generally useful),
Jones, J.L. and A.M. Flynn, 1993; Mobile Robots, Inspiration to Implementation, A K Peters, Wellesley Mass, 349 pages, ISBN 1-56881-011-3

I see lots of questions on the net about how to control devices from the PC parallel or serial port. Here is a free copy of an excellant book by Tim Hendtlass on Real Time Forth that has this info and more. (This is a zipped Postscript file, not HTML, 1012K).
You might also want to look at my recent Forth Dimensions article.

An index of my ForthWare Columns in Forth Dimensions.

Other Walking Robot related WEB pages

(a lot of these seem to be pretty slow links)

A Walking Machines Catalogue
* The ANIMATS (artifical animals) page
* The MIT AI Lab mobil robot page
* The Ublige Software & Robotics' Insecta page
* A Walking Vehicle
* Laurent Chabins' Robot Homepage

Dr. Everett (Skip) F. Carter Jr.
Taygeta Scientific Inc.
1340 Munras Ave., Suite 314
Monterey, CA. 93940-6140
voice: 831.641.0645
FAX: 831.641.0647
Taygeta's home page