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An anonymous reader submits: "Yesterday, Olaf Christ announced that he has the world's first TCP/IP-enabled Lego brick that can be used as a web server. Imagine the possibilities of connecting your collection of Lego Mindstorms to the Internet! He has ported the extremely small uIP TCP/IP stack to the Lego Mindstorms platform. uIP has also been used to run a Commodore 64 as a web server, and is ported to the 8-bit Ataris and laptop keyboard microcontrollers."

Johannes K. writes "Here is an apparently official news message sent out by LEGO as a response to the recent article on mindstorms in Business 2.0. In it, LEGO states that they think it is great that people hack mindstorms and write their own software for it; in fact, they are convinced it will increase the popularity of the product. (Now there's an attitude you don't see nearly often enough.) However, they do have to protect their trademarks, and LegOS is apparently one of the victims of that. Understandable, I suppose."

The Dev writes "The Pacific Northwest LEGO train club is attempting to break the world record for the longest LEGO train layout. They are setting up in the Seattle center right now, so you if you are in the area you might want to check it out. There are of course some Pictures on Brickshelf and a live webcam at the PNLTC website. The original announcement is here on Lugnet"

Jim Bumgardner took it upon himself to review two of the major Legos Mindstorms books out on the market. The first, O'Reilly's The Unofficial Guide to LEGO MINDSTORMS Robots, has been reviewed here before, but this review adds a comparsion to the second book. The second is from Apress Press, and is titled Dave Baum's Definitive Guide to LEGO Mindstorms (Technology In Action). Click below to learn how to use your Mindstorms more effectively. The Unofficial Guide to LEGO MINDSTORMS Robots & Dave Baum's De author Jonathan B. Knudsen & Dave Baum pages 266 publisher O'Reilly & Apress rating 8/10 reviewer Jim Bumgardner ISBN 1-56592-692-7 & 1-89 summary A broader overview of the Lego Mindstorms world, with coverage of alternativefirmware and building your own sensors. & An in-depth look at building and programming Lego Mindstorms Robots, witha particular emphasis on robot design and NQC programming. An Embarrassment of Lego (books) As you know, this year's best holiday gift for the important geek in your life is a Lego Mindstorms Robotic Invention System (RIS). Through strategic use of heavy-handed hinting, I managed to get my loved ones to purchase one for me a few weeks ago for my birthday. I've been obsessed with the thing ever since, and recently picked up copies of the two available books on the subject, which I'll compare for you below. Knudsen's book was reviewed here recently, while Baum's has not.

Since Robotics involves a lot of different disciplines, these books are going to have a pretty varied audience. In my case, I'm a longtime programmer and (extremely) novice robot builder who couldn't properly handle a soldering iron if my life depended on it. I'm not particularly interested in the chapters on the ins and outs of the C language, but very interested in things like gear ratios and sensing algorithms, which I never learned in school. The mileage you'll get out of these books will vary, depending on your background.

In the comparitive sections below, Knudsen's book (and Knudsen himself) will be referred to as K, while Baum's book (and Baum himself) will be referred to as B.

Cover First let's get the important stuff out of the way... K's cover is prettier, having a picture of a cute bunny wobot. It's an O'Reilly book after all.

Length B is 34 pages longer, but K uses a smaller font. I suspect B is a bit longer, but not by much.

Value Both are 25 bucks retail, and cheaper online (typically 20 bucks). B comes with a CD-ROM. K doesn't. The CD contains all the sample code, a copy of NQC and related utilities, some demos and a QuickTime movie showing the assembly of one of the simpler robots (tankbot). With the exception of the sample code, the CD-ROM is kind of superfluous.

Illustrations K uses photos, which have been tweaked in Photoshop to remove the backgrounds. B uses computer-generated models rendered in isometric projection (also known as "2 1/2 D" -- similar to what you see in the Lego Constructopedia). Both books' images are reproduced in B&W and suffer for it. It's particular hard to see (and count) the holes in black beams, for example.

B's illustrations are definitely clearer than K's, primarily due to the use of computer graphics. The isometric projection definitely helps in figuring out how pieces fit together. K's illustrations have helpful lists of pieces and arrows showing where they go, however there are problems due to poor constrast and fuzziness, as well as distortions introduced by the camera's perspective. Despite these problems, I managed to get even his most complex bot, Minerva, assembled relatively quickly.

Breadth and Depth In general, K has more breadth, while B has more depth. K's book includes more introductory material about robotics (e.g. "What is a Robot?"), while B jumps right into installation instructoins, assuming you know that stuff already (e.g. "Robotics is nothing new"). K covers a lot of ground, including various available software packages, such as pbForth and LegOS, while B sticks to RCX code and NQC. K also gets into some interesting topics not found in B such as Subsumption Architecture and building your own sensors. On the other hand, B gets much more in depth into specific programming and modelling issues. There are a lot more examples of algorithms for handling touch and light sensors, and discussion of specific problems that might arise and how to deal with them. B's line following algorithms are different, taking advantage of the percieved "gray area" on the edge of the black line, using upper and lower feedback limits, while K uses a "zig-zag" approach with a single threshhold value (when I implemented them, I found K's approach to be more effective - the "gray area" approach requires more minute adjustments). B also has good coverage of the strengths and weaknesses of the different mindstorm kits and parts.

Programming B coverage of algorithms is generally better, particular in his detailed handling of touch and light sensor issues. K has a nice example of Rodney Brooks' subsumption architecture, written in NQC.

B, being the author of NQC, makes NQC programming an intregal part of his book. Every program is shown in both RCX Code and NQC versions (although the RCX Code version is often seriously crippled (as needs be). Nonetheless, B appears to have more success in getting RCX Code to do useful things than K, who pretty much gives up on RCX Code after a couple of chapters. A personal note: I found RCX Code to be a general pain in the ass. Personally I'm not all that convinced that it is a better alternative for the novices it is aimed at. Especially when you have to go though such contortions to to get it to do such useful things. Is mouse pushing really all that simpler than typing?

Design Both books cover design reasonably well. I'd give the slight edge to B, who has a good design chapter before going into the specifics of building individual robots. The chapter not only covers some of the things covered in Fred Martin's "Art of Lego Design" paper, but also covers the use of Pulleys and Ratchets. K tends to weave similar design lessons directly into the chapters on specific bots. There are design issues in both books not covered by the other. B's discussion of stresses in bumpers is quite good. K has some nice examples of directional transmissions (which don't necessarily use the differential).

Robot Models Both writers' basic robots, are simpler and more utilitarian than their Lego counterparts from the RIS's Constructopedia, which tend to be a bit more fanciful (although K uses the all important wings parts for Minerva). Both books start with a basic tread robot which make ideal learning tools for learning to program with touch and light sensors. K's robot is geared down right away (for more power and lower speed). B doesn't gear down until the reduced speed is needed (for line following). B's book has designs and programs for 14 different robots, some mobile, some not. K only has 4 robots (all mobile robots). Both of these numbers are misleadingly high, since some of the bots are quite similar. Some of B's more advanced bots require extra parts not included in the RIS kit. In some cases, the extra parts are needed to explain an interesting concept, like rack and pinion steering. B includes some designs for some interesting non-mobile robots, such as a brick sorter and a vending machine, which reads lego "punch cards". Both books' final robot is an armed robot - apparently the holy grail of many robot designers (there's one depicted on the cover of the RIS kit which I'm guessing can't be built with the stock parts). B's robot, RoboArm, requires an extra motor and bricks. K's robot, Minerva, manages to do a lot of stuff using all stock parts from a single 1.0 RIS kit (he accomplishes this via a directional transmission and an ingenious one-motor grabber arm borrowed from Ben Williamson). When I built this model using my 1.5 kit (which has a slightly different allotment of pieces), I found I was missing a couple bevel gears needed to complete the model (I borrowed some old style "thin" bevel gears from my daughter's Lego bucket, but they're very flimsy). This bot certainly accomplishes a lot with relatively spare resources, although it is perhaps pushing the envelope too far, as the "arm" assembly tends to require frequent attention, as the author notes. I found it useful to test more advanced designs with a spare 9V battery box I had left over from an old Technic kit. You can also use your computer as a remote, for this purpose.

Online References K's online references are more thorough. Both books have the most important URL, of course, which is www.lugnet.com - the center of the online Lego universe.

Timeliness B, a little later to press, includes coverage of RIS 1.5, and differences between RIS 1.5 and 1.0 (they are relatively minor).

Writing Style K tends to wax a bit more eloquently. I like his prose better. B is a bit less philosophical and tends to dive right into discussions of procedures and problems. This has its merits too, as he devotes a little more time to the nitty gritty.

Conclusions In some ways, these books are a little bit superfluous. The whole point, it seems, of the Lego Mindstorms kits is to learn by doing - by playing with them. Also, a lot of the material in the books, such as coverage of NQC, LegOS and other software packages, can be easily found on the net. Nonetheless, I found myself compelled to suck up both books, and I'm sure I will ultimately use some of the tips and tricks I've learned from both.

The two books complement each other very well, and if you have the interest and the bucks, I would spring for both. Knudsen's book provides a broader overview of the Lego Mindstorm's world and robotics in general, while Baum provides a lot of valuable technical information on solving specific problems. Purchase The Unofficial Guide at fatbrain or grab Dave Baum's at from fatbrain as well.

Table of Contents (Baum)

• Preface
• Introduction
• History

• Part I-Building Fundamentals
  • Chapter 1 - Mechanics
  • Chapter 2 - Motors
  • Chapter 3 - Sensors
  • Chapter 4 - Basic Vehicles
• Part II-Programming Fundamentals
  • Chapter 5 -NQC
  • Chapter 6 - Robolab
  • Chapter 7 - Sequenced Operations
  • Chapter 8 - Event Based Programming
  • Chapter 9 - Making Decisions
  • Chapter 10 - Using Feedback
  • Chapter 11 - Data Logging
  • Chapter 12 - Using more than one RCX
  • Chapter 13 - Advanced Programming
• Part III-Robots
  • Chapter 14 - Garbage Truck
  • Chapter 15 - Copy Machine
  • Chapter 16 - Vending Machine (or ATM)
  • Chapter 17 - Robot Tag
  • Chapter 18 - Elevator
  • Chapter 19 - Brick Sorter
  • Chapter 20 - Electric Train Controller
  • Chapter 21 - Stair Climbing/Walking
  • Chapter 22 - Multiple-RCX Robot
  • Appendices
    • Appendix A. Other Resources
    • Appendix B. On-line Resources
    • Appendix C. Robolab Development Environment
    • Appendix D. Lego CyberMaster product
  Table of Contents (Knudsen)
  • Preface
    
  1. Welcome to MINDSTORMS
     • What Is a Robot?
     • Mobile Robots
     • What Is MINDSTORMS?
     • What Now?
     • Online Resources
  2. Hank, the Bumper Tank
     • About the Building Instructions
     • Building Instructions
     • A Simple Program
     • Wheels
     • Bumpers and Feelers
     • Gears
     • Multitasking
     • Online Resources
  3. Trusty, a Line Follower
     • Building Instructions
     • Some Tricky Programming
     • The Light Sensor
     • Idler Wheels
     • Using Two Light Sensors
     • Online Resources
  4. Not Quite C
     • A Quick Start
     • RCX Software Architecture
     • NQC Overview
     • Trusty Revisited
     • Online Resources
  5. Minerva, a Robot with an Arm
     • Building Instructions
     • Programming
     • Directional Transmission
     • Pulleys
     • Mechanical Design
     • Two Sensors, One Input
     • Where Am I?
     • Online Resources
  6. pbFORTH
     • Replacement Firmware
     • pbFORTH Overview
     • About Forth
     • pbFORTH Words
     • An Expensive Thermometer
     • Minerva Revisited
     • Debugging
     • Online Resources
  7. A Remote Control for Minerva
     • Two Heads Are Better Than One
     • The Allure of Telerobotics
     • Building Instructions
     • Programming the Remote Control
     • Programming Minerva
     • Online Resources
  8. Using Spirit:ocx with Visual Basic
     • You May Already Have Visual Basic
     • About Spirit:ocx
     • Calling Spirit:ocx Functions
     • Immediate and Delayed Gratif ication
     • Programs, Tasks, and Subroutines
     • Tips
     • Retrieving the Datalog
     • Online Resources
  9. RoboTag, a Game for Two Robots
     • Building Instructions
     • Subsumption Architecture
     • Online Resources
  10. legOS
      • About legOS
      • Development Tools
      • Hello, legOS
      • Function Reference
      • New Brains for Hank
      • Development Tips
      • Online Resources
  11. Make Your Own Sensors
      • Mounting
      • Passive Sensors
      • Powered Sensors
      • Touch Multiplexer
      • Other Neat Ideas
      • What About Actuators?
      • Online Resources
  • A: Finding Parts and Programming Environments
    
  • B: A pbFORTH Downloader
    
  • C: Future Directions
    

SwiftOne writes "A professor of mine pointed this link to Lego Catalog for 1999, which includes pictures of several Star Wars Lego sets...I see X-wing, Y-Wing, Tie Advanced, Air Speeders, a Hoth set, and the Prequel 1 poster redone in Lego. Can you imagine combining this with the Mindstorms? If I use all of my previous sets, I may be able to get a reasonable Death Star. Note: The Lego storm troopers look a little short...:) "