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Erco's Figure Eight Challenge - Page 19 — Parallax Forums

Erco's Figure Eight Challenge

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  • MikeDYurMikeDYur Posts: 2,176
    edited 2016-11-10 00:06
    Heater. wrote: »
    Hey, I'm just this guy, y'know.

    Rummaging in my junk box now:

    Propeller - check.
    Motors - check.
    Chassis/Boxes - check.
    MOSFETS - check.
    Sensors - ...

    .... rumage, rumage...ColorPal.... Hmm. That could do it.




    Hey guy's I budged him, we need to pester him a little, or he will put it on a back burner and turn down the heat.
  • ercoerco Posts: 20,256
    Well Heater sure talks a good game anyway... :)
  • ercoerco Posts: 20,256
    Booya, EIGHT! Just two more to double digits unless someone breaks my streak!

    As suspected, treads suck consistency-wise. It took several tries and luck to get fairly close in this video. Every test run wears down the alkaline cells (which also suck) and it goes slower. Which means not as far with the simple timing commands used here.

  • Erco,
    I gather your figure 8 is being done withoutthebenefit of odometers .
    Jim
  • ercoerco Posts: 20,256
    Yup, just using timing commands here. Wheels are so much easier than treads.
  • ercoerco Posts: 20,256
    I built up this Feetech 4WD chassis today. Reckon I'll "8" it without anyone interrupting my streak. I done lost track of how many 8's I have in a row. Have to page back sometime.

    1536 x 864 - 378K
  • ercoerco Posts: 20,256
    Since two motors on one side are binding, this bad boy will turn best in one direction. The Fig 8 must wait!

  • ercoerco Posts: 20,256
    edited 2016-12-19 18:58
    Laser Trike blazes my ninth "eight" in an uninterrupted row. One more and I'll make it into double digits while everyone's out Christmas shopping! Edit: Updated video

    Still experimenting with speed, sampling and steering rates. The high pitched sound is the beeper toggling every time the sensor is sampled. Those ten-cent beepers are solid gold.



  • The F8 test is great, the bot looks very animated.

    I need to get another pair of motors for that chassis you gave me. Any recommendations?
  • ercoerco Posts: 20,256
    edited 2016-12-19 19:24
    That chassis has cutouts for those specific 9g servo-sized motors. You need more of those? Didja borrow those for another project, blow 'em up, or you just wanna hotrod the chassis with different motors?

    Edit: Or you could get in on my next Feetech order from China and get some bolt-in 9G digital CR servos... I'm sure our pal Gordon wants some too.

  • You gave me 2, I want to make it AWD. I should probably match what is on there now, got a link to em?

    Thanks.
  • ercoerco Posts: 20,256
    Not readily available, no link. Feetech has a website but most of their robotic stuff isn't even listed: http://www.feetechrc.com/product-category/ft-robot/

    You would think your servo/gearbox would be listed there somewhere but it ain't.

    I email their customer service directly and it takes a few replies and iterations and translations to place an affordable order. Shipping adds up very quickly.
  • 2WD is fine then, it has the caster :)
  • ercoerco Posts: 20,256
    Just tip it up and make it a balancer. Saves 2 motors!
  • WhitWhit Posts: 4,191
    Great new sensor Sir erco! Saw the demos on your YouTube Channel...

    New title - Erco, the 8th or erco VIII.
  • erco wrote: »
    Just tip it up and make it a balancer. Saves 2 motors!

    Good idea, I'll give it a shot.

  • ercoerco Posts: 20,256
    Hey Whit's checking in. NOW it's a party! Merry Christmas, Boss!
  • Here is my humble attempt at a walking figure eight. It is made from Minds-i parts, uses a Propeller Activity board and is programmed in Blocklyprop. Notice the red line on the floor to see the calibration of the figure eight. HEE HEE I DID IT! The Blocklyprop code is attached. You can all tell me how to make it better as I am getting my feet wet with it. Love it too. A lot of fun to use.
    626 x 606 - 59K
  • ercoerco Posts: 20,256
    Perfect! Great job, welcome to Team F8C!
  • ercoerco Posts: 20,256
    Can't let Carol have all the fun! My new trike bot takes a shakedown cruise. Surprisingly accurate & consistent, even using alkaline batteries & simple timing commands.

  • PublisonPublison Posts: 12,366
    edited 2017-01-19 20:14
    erco wrote: »
    Can't let Carol have all the fun! My new trike bot takes a shakedown cruise. Surprisingly accurate & consistent, even using alkaline batteries & simple timing commands.

    That is wicked fast! Good job!
    .


  • ercoerco Posts: 20,256
    edited 2017-01-19 21:30
    Publison wrote: »
    That is wicked fast!

    Especially since there's no motor braking, or even reverse here. Just PWMing 50% (yes, faster is possible) through a DC motor using a mosfet, so I had to allow for power-off coasting down at the end.

    Ramping the motor down? No time for that!

  • WhitWhit Posts: 4,191
    Wow!
  • As Requested, re-posting in this thread.

    I would like to introduce my robot call 'zBot' to the Parallax forum community. I have been working on it as a winter project for a few years. Last winter I started working on an auto-pilot. I needed a test environment and chose the "Figure 8 Challenge".

    The robot I am developing is meant to operate in larger spaces (10 x 10 meters). It was never intended to be used to perform small accurate movements. For me it was an interesting software challenge to coax the auto-pilot to behave correctly at this scale. On my 'Still to Do' list I have now added the need for an "Auto-Pilot 2.0" that will do cursive writing.

    "
  • Malcolm, I have been meaning to make a comment on your great little robot writers. I'm going to be following your progress, as your robot's graphical interface is very interesting. I wish my cursive was that smooth.
  • ercoerco Posts: 20,256
    Recursive writing is even harder!
  • Heater.Heater. Posts: 21,230
    I can recursively write this "I can recursively write this "I can recursively write this "I can recursively write this "I can recursively write this "I can recursively write this "I can recursively write this "..." easily." easily." easily." easily." easily." easily." easily.
  • <A> ::= <B><A>
    <B> ::= "I can recursively write this"
  • Heater.Heater. Posts: 21,230
    What language is that?

    It looks like it has a different output to the algorithm I was hinting at above.

    I might guess it would be:

    <A> := "I can recursively write this \"<A>\" easily."

    If we can introduce double quotes with escape sequence as shown.
  • Heater. wrote: »
    What language is that?

    It looks like it has a different output to the algorithm I was hinting at above.

    I might guess it would be:

    <A> := "I can recursively write this \"<A>\" easily."

    If we can introduce double quotes with escape sequence as shown.

    Getting a little off topics guys. Let's see some robotic videos.


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