February 23, 2007
The Science and Technology Set magnet game was proving to be fun.
The set has lots of beams.
The Carnegie Mellon Robotics II tree caliper seemed a good tool to measure bricks.
I have been unhappily surprised with the accuracy and not because of the need for zeroing out.
I find that the studless beams bend more than the regular LEGO beams.
That may account for the connectors getting bent and broken
now with the NXT sets compared with the RCX sets.
The original program for the Tree measure was giving big numbers for thin things.
The range for completely closed could be from 2375 to 2422.
We worked in stages to have the NXT do the math for us.
First we checked the zeroing out on the display.
Zero was some times 0 and sometimes 1.
Then we subtracted the "closed" reading.
That was nice because at least small objects would have little numbers.
Measuring 8 beams wide gave a number about 1430.
So we divided the reading by 179 to get a Brick Count.
This actually worked when we demonstrated it to the rest of the class.
