To LUGNET HomepageTo LUGNET News HomepageTo LUGNET Guide Homepage
 Help on Searching
 
Post new message to lugnet.org.us.laflrcOpen lugnet.org.us.laflrc in your NNTP NewsreaderTo LUGNET News Traffic PageSign In (Members)
 Organizations / United States / LafLRC / 110
109  |  111
Subject: 
Re: line follower?
Newsgroups: 
lugnet.org.us.laflrc
Date: 
Wed, 12 Oct 2005 17:11:08 GMT
Viewed: 
824 times
  
In lugnet.org.us.laflrc, Steve Hassenplug wrote:
   Bryan: made any progress on that line follower?

Gee - funny you should ask :)

Since none of my ideas were going to look real original any more after playing around at your house last weekend, I resolved to make the rack & pinion approach work better.

So, I redesigned the drive train and eliminated the differential. I went to 1:3 gearing from a motor directly to each rear wheel so that I could obtain the desired robot velocity if I could ever get the line following to work well enough.

Then I redesigned the front end...so now I have the light sensors mounted on an arm that swings side to side (instead of just moving back & forth). The arm pivots on a point centered at the front of the car and is linked 1:1 with the front wheels (the turn angle of the wheels is the same angle the arm is turned to). By playing with the arm length, I impact how fast it goes off/on the line (the sine of the angle x the length of the arm is the distance off center the arm is at).

With this done, the car was following the line at about 30-35 cm/sec. This represented the soft limit of the 2 sensor & simple SW approach. I am sure I could get more...but not that much more...

So, I bit the bullet and went to a 3 sensor approach. I have an initial cut at the SW done and first results look like about 50 cm/sec...I need to start refining the SW & arm length to achieve faster speeds. Right now I have the speed set at 75% on, 25% braking...so there is still plenty of room for improvement.

It looks promising...What I need to do is put together a course instead of using the test oval...I was given a couple of old FLL mats that I could use for a course...just haven’t done it yet.

B



Message has 1 Reply:
  Re: line follower?
 
(...) If it's any help, my first line-following event (NEIRG, with up to 135° sharp turns) I resolved to start from scratch and "be original". By event day, I ended up with Ben Hur's little brother quite unintentionally. But it worked. (...) Yes, (...) (19 years ago, 12-Oct-05, to lugnet.org.us.laflrc, FTX)

Message is in Reply To:
  line follower?
 
Bryan: made any progress on that line follower? (19 years ago, 12-Oct-05, to lugnet.org.us.laflrc)

3 Messages in This Thread:

Entire Thread on One Page:
Nested:  All | Brief | Compact | Dots
Linear:  All | Brief | Compact

This Message and its Replies on One Page:
Nested:  All | Brief | Compact | Dots
Linear:  All | Brief | Compact
    

Custom Search

©2005 LUGNET. All rights reserved. - hosted by steinbruch.info GbR