i finaly got my robot to log the sonar sweep to file. really the hard part was the control code to make the servo motors go to an exact orientation as quickly as possible without osculating too much, basic control theory. the rest was making the graphs look pretty. while it draws the graph on the screen as x,y vectors, its really just a linear mapping of polar coordinates, since the ultrasonic sensor rotates on the turret, the motor orientation being the angle, and the detected range being the length. the lack of trig functions and floating point numbers on the nxt is really pissing me off. tomorrow il write (and i use the term loosely, since its flowchart programming) some code to sort through the data. best bet will be to look for long range reflections repeated over consecutive angles, then pick the widest sweetspot, turn the bot that way and fire up the slow nxt motors so the robot can get there, eventually. should order that motor multiplexer so i can use those old skool motors that came with the first mindstorms set. they haul ass with no gear trains. if i want some real go, i could also use one of my lego pneumatic engines and rig up some kinda automatic transmission.
