Shop OBEX P1 Docs P2 Docs Learn Events
Line followers and maybe, dot followers — Parallax Forums

Line followers and maybe, dot followers

LoopyBytelooseLoopyByteloose Posts: 12,537
edited 2007-02-08 17:53 in General Discussion
Well I am working on a line follower with six CNY70 sensors.
Intially, I considered just a high/low indication via an op amp from each sensor.

It is quite tempting to use a Propeller to have all the readings be Analog to Digital.· But since line following has been around for quite a while, I may try for following 1" diameter dots instead.· This would up the required intelligence of the robot.· With regular spacing of the dots, the robot would have to calculate speed and expect to see a dot.· The width of the reading would have to be monitored too.

Anyone interested?

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
"If you want more fiber, eat the package.· Not enough?· Eat the manual."········
···················· Tropical regards,····· G. Herzog [noparse][[/noparse]·黃鶴 ]·in Taiwan

Comments

  • Dennis FerronDennis Ferron Posts: 480
    edited 2007-02-08 03:11
    How about making it follow a trail of coins?
  • stev0tronstev0tron Posts: 12
    edited 2007-02-08 03:51
    Way to think outside that 'ol box! haha.· Me and the team I'm have done some line following things before, but never a dot following.· Would that be black·and white?· Color would be interesting.· Maybe use QTI's if its black and white, or maybe black or white circle with something that can identify shapes or perimeters.·
  • Dennis FerronDennis Ferron Posts: 480
    edited 2007-02-08 06:48
    Come to think of it I think a dot-following event would make the contestant's robots demonstrate more "intelligence" than line following. You can implement a simple bang-bang algorithm to follow the black/white edge of a line, but there's really very little thinking involved; it's just a matter of balancing signals. But a dot-following robot has to have some kind of mental model of its situation in order to tell the difference between going off course and there simply being a gap between dots.

    Oh, and a dot-following robot could tell where it was by counting the dots. The competition could even require that the robot make different turns at certain dot numbers, or a free-form event could be held with a grid of dots.
  • Bruce BatesBruce Bates Posts: 3,045
    edited 2007-02-08 08:41
    I want to be the second one through, so I can have mine play CONNECT THE DOTS! <oops> smile.gif

    Bruce

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    <!--StartFragment -->
  • Beau SchwabeBeau Schwabe Posts: 6,568
    edited 2007-02-08 16:40
    "Oh, and a dot-following robot could tell where it was by counting the dots."

    Dennis,

    How about other bots on the same course that would communicate to each other a "location" that may be more difficult to navigate.
    A histogram of how many "retries" in a specific location so successors would learn from a predecessors mistakes. A communicative mapping if you will.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Beau Schwabe

    IC Layout Engineer
    Parallax, Inc.
  • FranklinFranklin Posts: 4,747
    edited 2007-02-08 17:34
    How about short line segment following where the line segment would indicate which direction the next segment was from there.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    - Stephen
  • LoopyBytelooseLoopyByteloose Posts: 12,537
    edited 2007-02-08 17:47
    Wow! I hadn't considered that dots could actually help the robot determine its own location by counting them.

    What I was considering was just going to a stationery store and buying a package of 1" diameter adhesive dots. The placement would be with 1" spacing between them at most. They may actually be too much and 1/2" might be a better approach to get started.

    It certain does revive line following as a competative challange. Let me know if anyone has an event venue they would like to get going.

    Franklin,
    I think the round dot would make the bot have to figure out direction rather than 'follow the indicated direction' of an edge. There may be a valid reason to use a shape other than a dot at an intersection; especially a Y intersection. But in most cases, the beauty of the programing is in the dot itself.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    "If you want more fiber, eat the package.· Not enough?· Eat the manual."········
    ···················· Tropical regards,····· G. Herzog [noparse][[/noparse]·黃鶴 ]·in Taiwan
  • LoopyBytelooseLoopyByteloose Posts: 12,537
    edited 2007-02-08 17:53
    Beau,
    Yeah, having the Bots communicate via IR could really create are very different environment and conceptual challange - group behavior.

    The goal could be to work through a maze of dots in the shortest distance as teams of 3 or 4 Bots or to avoid being the last Bot to arrive home. This would allow different bots to select left or right turns to explore Some kind of collision avoidance could be involved as well.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    "If you want more fiber, eat the package.· Not enough?· Eat the manual."········
    ···················· Tropical regards,····· G. Herzog [noparse][[/noparse]·黃鶴 ]·in Taiwan
Sign In or Register to comment.