Wednesday, November 22, 2006

Mindstorms NXT Test Run

After the AISNE Tech Directors' meeting, the folks at Belmont Hill threw down a challenge to see if we would like to "lego-a-lego" with a little friendly competition. Not one to back down, or miss a chance to expense some new Lego products, I got the new NXT kit. First, the retail package *finally* has Mac-compatible software; and it appears to be the same software sold in the educational markets. In any case -- what you're seeing here is the retail version:



The software is very different, but the concept of object oriented programming with tiles is the same. The crazy wires and threads from the old Mindstorms are pretty much gone, replaced by something called a "sequence beam". Big sigh of relief, tho you still need wires for more advanced functions; was so frustrating to see the old wires folded behind tiles and never know where the command strings were broken. The icons are not as strait-forward, however (or maybe I'm just used to the old ones), and you have to pay attention to the tiny-tiny radio buttons and sliders in the control pane. I also wish you could zoom in and out of the program view; big programs become very hard to see. There is a "Map" tab, which makes navigation easier, but it provides a limited view.

You can also import the old Mindstorms tiles (IMHO, still confusingly referred to as "blocks") from the web site's update page:

NXT Software Updates

The assembly tutorials, however, are a big step forward -- you can see those famous Lego "graphic instructions" in a viewer pane called "Robo Center". I used to do this with MacBrick CAD, and there was really no way to dimensionally imagine or walk the kids thru custom assemblies. Boy, I wish there was a way to add my own assemblies into the Robo Center (it's written in Flash, so it might be possible to import .swf files). There's also a little "Portal" tab where you can link and get more resource files and projects.

Inside the box, the whole package is separated into those little perforated baggies, as you would expect -- but there is a special box that says "Start Here!". It contains the first set of instructions and all the parts to make the basic "tribot" used in the tutorials. It's so easy to get started -- that plus the programming tutorial is so basic, it's easy to see that kids can get going real fast.



The NXT has Bluetooth -- if you ever used the old IR comm-tower you'll know how amazing this improvement is! The old IR signal was so weak, that you often has to cover the tower and the RCX brick with a shoe box in order to get a good download.



However, the basic tribot does virtually nothing, so you want to get right to the big claw pieces. This is not a challenging build as far as Lego construction goes. I don't like the big crazy fat cables. You have to keep the cables from interfering with the wheels and sensors, etc. The new cables are not easy to keep "tucked". Wire management was always an issue with the old system, too, tho at least Lego provided bricks cut with slots to snap-in the old, thinner cables. But the new motor units are tremendous; they are much easier to package around the NXT brick. Using the Technic beams and pins as opposed to regular Lego bricks makes the mechanical engineering much more strait forward.



Here is the completed "tribot" with claw arms. The basic instruction here is: go to ball, stop, when user claps hands, arms grasp ball, robot turns, and brings ball back to "Start" point:




I do miss the regular bricks, however -- there is not one regular Lego brick in the kit! Not even a minifig. So ...



Ah. That's better.