Lego's Little Mind Builder

The toymaker's joint effort with MIT lets kids design a robot and program its brain

When my sons, now college students, were little, a favorite pastime of theirs was a Learning Co. game called Robot Odyssey. In this Apple II program, children (and adults) used various simulated sensors and circuits to build onscreen robots that could solve a set of progressively more difficult puzzles.

Robot Odyssey is long gone, but the idea is back, and you no longer have to settle for simulations using crummy Apple II graphics. The $200 Lego Mindstorms Robotics Invention System is the result of a collaboration between the Danish toymaker and Massachusetts Institute of Technology's Media Lab. An earlier result of this joint effort, Lego Logo, has been used in elementary schools for a decade.

ICON EASY. The kit consists of more than 700 Lego pieces in a staggering variety of shapes, a programmable controller called the RCX, two motors, and touch and light sensors. You start by constructing a robot using the RCX as the core. Since my previous experience with Lego consisted mostly of stepping on pieces barefoot in the dark, I found this step frustrating. But I suspect the average 12-year-old could manage it a lot better.

Once your robot is built, you turn to a PC for programming. Mindstorms' software, which runs on any Windows 95 computer, uses an ingenious technique. You build a program by connecting icons representing commands to build a string of instructions--no typing needed.

Although the number of commands is limited, they can create programs of considerable sophistication. A kid with no programming experience can write a routine that lets a robot respond to something, such as contact with touch sensors or a change in the light level. I wrote a program to get my robot to run an obstacle course.

Once a program is complete, you transfer it to the RCX using an infrared link that plugs into a PC's serial port. Press the "run" button on the RCX, and the robot executes the program. If the robot doesn't work as expected--and it probably won't on the first try--it's easy to modify the code and try again. For example, I had to do a lot of testing to see how long to run the robot in reverse to back off from an obstacle before proceeding.

WEB HELP. One of the things I like best about the Lego system is the way it invites children to explore and innovate rather than just follow directions. A tutorial shows how to build a simple robot. The software then offers several design challenges, such as a robot that can run an obstacle course or one that follows a black line on the floor. Both the software and an accompanying pamphlet offer tips on how to construct the robot, but details are left for the builder to figure out. And there are lots of sample programs that can be modified. Lego (860 749-2291) also makes good use of a Web site,, for more tips and challenges. In addition, kit owners can get their own home page on the site where they can post their design ideas.

Some children will find this open-ended approach frustrating. Others will find it stimulating. I think you have to know your kid before taking the plunge. The set should be in toy stores in North America and Britain in October, with Europe and parts of Asia planned for next year.

Like the long-ago Robot Odyssey, this robotics invention kit straddles the line between a toy and an educational product. I think that's a boundary where a lot of learning can take place.

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