วันอังคารที่ 4 มิถุนายน พ.ศ. 2556

LEGO Mindstorms NXT: First Impressions

Lego Course for Kids with Smartkids powered by PlayLego at Future park Rangsit Pathum thani 

  Speaking of Personal Robots, LEGO made a definite first splash in this area several years ago when it released its LEGO RCX as the Mindstorms Invention System. Designed for ages 10 and up, the RCX was probably an ideal toy for a kid. Other than the RCX brick itself, most other parts (sensors, motors) were standard LEGO pieces that one even had in their own other LEGO kits. The genius of RCX was that it integrated well with existing LEGO pieces and more or less looked the same as any other LEGO piece. The same wire connectors worked for connecting sensors and motors to the RCX. A graphical 'programming language' was used to design control programs. Several computer science departments turned to RCX (probably the best reverse engineered commercial electronic artifact of its times) and designed several innovative courses, labs, and programming languages (from C, NQC, LISP, JAVA, and even ADA!). So I just received the Mindsotrms NXT kit from LEGO. This, next generation LEGO kit is a definite move away from the RCX model. The brick controller itself is not too different from the RCX: about the same size, bigger LCD display, three motor ports, four sensor ports (one more than the RCX), a built-in bluetooth recevier (to replace the IR module) and a more up-to-date USB port. The brick itself seems to have better places to anchor other LEGO connectors to build a robot body. The connectors for motors and sesnors have deviated away from LEGO connectors to phone-style jacks and cables. This of course means that you are out of luck with using your old sensors and motors. For $250.00 the kit inlcudes the following: the NXT brick, a sonar sensor, a sound sensor, a touch sensor, an IR sensor that can sense color as well as proximity, three servo motors (yes servo, so they offer precise control) Each sensor is approx 0.75inch x 0.75inch x 1.75inch in dimensions, with the exception of sonar which is bigger and has a T-shape for 2 sonar mounts. The box also comes with an assortment of LEGO pieces that resemble a collection from one of custom LEGO kits as opposed to the generic LEGOs. There are the standard pieces...connectors of various kinds, and there are also oddly shaped ones (elbows, bent beams, etc.) mostly in gray, black, or white color schemes with some orange accents. The box comes with a booklet that has instructions for building a basic mobile robot which can then be used for adding onto for other projects included on the CD. The box claims you can get started with a robot in 5 min...yeah right. Takes longer to install the Mindstorms software itself! All claims aside, I was able to easily build the base and then after installing the software and getting into Robolab, I started building the first project, Tribot: it has grippers in front that can be opened and closed (custom parts) to grip and lift a colored ball. The robot can sense the presence of a ball (sonar), move to it, stop when it gets there (touch sensor). Then when you clap with your hands, the sound sensor enables a sequence to close the gripper and then move the robot back. This took me at least 2 hours and I am not a LEGO novice...much time was spent fishing for the right pieces demanded in the construction manual...did I say there are several tiny, custom peices here? Programming the sequence was easy...but there are bugs in the version shipped. Overall a good experience putting together various control components into a program. In the end I had a robot that got to the ball, closed (more like slapped!) its grippers on it...and the ball always bounced right out of the claws! An afternoon's labor... So, what do I think? I felt like I was in the New Yankee Workshop (the PBS show with Norm Abram the master craftsman who has a special tool for every little job!). Like the RCX, I think it'll be a good toy for kids. This is supposed to be an open-source platform so there are (or will be) other development environments. I also saw that there is (or going to be) a Microsoft Robotics Studio interface for the NXT brick. My thoughts on those when I get to play with them...

ไม่มีความคิดเห็น:

แสดงความคิดเห็น