Servo - May 2009

makes robotic competitions useful as a learning exercise is the breadth of knowledge required.

This sort of exercise wouldn’t have been possible a few years ago, simply because it would have been almost impossible for a non-programmer to pick up C/C++ or even Basic in a few minutes, or a non-technical student to learn how to solder and handle sensitive components. The ‘plug and play’ nature of the Mindstorms NXT enabled students without prior experience to build robust robots in minutes.

The point is that robotics has a place in education outside of the traditional science and engineering application. This is in part because of the novelty of robotics and in part because even the simplest robots have multiple systems that can each serve as teaching points for everything from logic to physics.

Perhaps you teach a non-technical class where team-building is essential to success. If so, consider employing robotics as a convenient, highly visible focal point. Then share your experience with our readers. SV

Dear SERVO:

I wanted to let you know I enjoy Fred Eady’s articles and code examples. I am in the process of developing a fairly complex system to completely control the navigation and functionality of a large model boat (I live on a lake). This system accepts a predetermined route consisting of headings and lat/lon end-of-segment waypoints entered from a PC, and controls throttle and rudder, as well as a bilge pump if necessary. The main board directly mates to one of those surplus 2x16 display boards with the four buttons and is

PIC18F2525 based, with the RS-232 dedicated to the initial course download. It also does the heavy navigation lifting. A second board — based on a 16F876A — accepts RS-232 input from a raw GPS sensor, picks up the appropriate sentences, and runs a long term moving average on actual lat/lon position. It also maintains rudder position and produces the PWM for the boat servos. I'm using SPI between the two main boards to pass real-time coordinates and speed back to the first board, where the PID determines necessary course corrections and returns them via the SPI slave "return."