[NXT] - dFlex Wall Follower

[Jetro]

I keep forgetting this forum isn't only Technic, but also MINDSTORMS... I'd like to present my latest build: the dFlex Wall Follower.

First a bit of background. Dexter Industries is a fairly new company that produces sensors and switches for the LEGO MINDSTORMS NXT. Last month they had a contest to promote their new dFlex sensor and I was fortunate to be one of two people whose proposals were rewarded with a free dFlex sensor.

I've now had some time to work with this sensor and try it out in different set-ups and I'd like to show you my dFlex Wall Follower. Laurens Valk kindly gave me permission to use his Explorer from "The LEGO MINDSTORMS NXT 2.0 Discovery Book" as a test base to which I added a front bumper, and this is the result:

There front bumper is really simple and there are a couple of pictures showing how it is attached to the Explorer on Flickr.

Of course a robot isn't much of a robot until you see it in action so here's the video:

The wall follower is programmed in NXT-G. Dexter Industries have made available two different NXT-G blocks for the sensor. In this program I have only used the first block and all calculations for the proportional control are done with the raw output of that block. However if you use the second block, you can easily calibrate the sensor within a specific range and get a bend percentage inside that range from the second block... something to use in another bot.

[DLuders]

Whoa! This sensor would sure do well in a FIRST Lego League competition! It doesn't have to be used only in "robots" -- it could be used as a "minesweeper" on this NXT Light Explorer tank: http://www.eurobricks.com/forum/index.php?showtopic=43669 .