FRIENDS OF THE TURTLE

David D Thornburg, Associate Editor

Robots Are Turtles, Too

With the continuing development of excellent turtle graphics environments on every computer with a halfway decent display, it is easy to lose sight of the fact that the turtle was originally a computer-controlled robot. The power and ease of turtle graphics have allowed the screen-based progeny to totally eclipse their mechanical forebears.

While Friends of the Turtle supports and encourages the use of mechanical turtles such as the Big Trak and the Terrapin Turtle, we haven't received many comments from the users of these devices. Because of the recent entry of the Heath and Androbot robots (see this month's Computers And Society column), I think it is about time for us to make it clear that we will grow even more aggressive in our support of turtles – both mechanical and screen-oriented.

Although people who use turtles often share a common programming language, the interests of people who use one type of turtle are different from those who use the other. The speed, precision, color, and available complexity of a display turtle present challenges of a different sort from those of a mechanical, imprecise, and (relatively) slow robot. Where the user of screen turtles might be interested in the creation of landscapes, the user of a robot may be more interested in solving mazes.

Both people may use the same language (e.g., Logo) and computer system, but each has a different set of objectives. We want this column to be a comfortable home to all turtle users. You can help make it one by sharing your applications with us.

For example, one marvelous application for the Big Trak was developed by Katie Thornburg for use with school children between second and sixth grades. She uses several dozen pieces of 1 × 4 inch wood cut into 13-inch lengths (the length corresponding to one forward unit of Big Trak motion). She places these pieces of wood on a 4 × 8-foot sheet of pegboard to create a maze that each child must "program" his or her way out of.

By having the constraints of a maze (rather than a more general problem, such as moving in a square path), the children are highly motivated to create error-free programs. Additional challenges can be created by having two teams race against each other, or by having each of two teams construct a maze to be solved by the other team. This inexpensive addition to the Big Trak has greatly increased the value of this tool in the computer classroom.

Turtles At The CES

There were at least three things I saw at the Winter Consumer Electronics Show that are of value to friends of the turtle. The first of these was the introduction of the Mattel Aquarius computer (currently selling for under $170) with an under $100 Logo cartridge. While the graphics resolution on this computer isn't tremendous, I was impressed by the fact that Mattel's Logo was developed by The LISP Company. Since Logo is a user-friendly version of LISP (LISt Processing), I felt comforted to know that this would not be a pure turtle graphics package passing itself off as Logo.

The second delight was a preview of a forthcoming turtle graphics package for the Commodore 64 from HES. I am very impressed with this program. Once I get a copy, I will review it in this column.

The third development of interest was the introduction of a new company, Androbot. This company, founded by Atari founder Nolan Bushnell, introduced a computer-operated robot named TOPO and a self-contained android named B.O.B. (Brains On Board). TOPO is described in this month's Computers And Society column, so I won't say any more about it here.

B.O.B. is a thoroughly engaging creation programmed to "seek" people out and initiate "conversations" with them. To help with this task, B.O.B. sports five Polaroid ultrasonic position sensors to map the environment, and two IR sensors to find people (and other warm bodies such as stoves, spotlights, etc.). These sensors feed information to a central computer that uses three 8088 processors with up to 3 M bytes of RAM.

What makes B.O.B. so interesting is its potential to dynamically program itself. In principle, B.O.B. can make a map of a room and develop an optimal path for performing some task, such as vacuuming a rug.

B.O.B. charmed everyone who saw it - especially when it became clear that no one knew exactly what B.O.B. was going to do next, or how it was going to get out of a jam.

Androids using adaptive programming techniques represent the next generation of robots. If you write programs using a list processing language such as Logo, you have all the tools you need to develop adaptive programs yourself.

Robots can (and will) be very sophisticated in the near future. But they are a lot of fun as well. So don't forget that Friends of the Turtle is a place for ideas on both screen and mechanical turtles.

Let me hear from you!