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Baybots 2012 Table Run

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  • Baybots 2012 Table Run

    Baybots 2012 Practice Table Run - about 180 points give or take depending on how many groceries (simulated here) stay on the table.

    http://www.youtube.com/watch?v=4vDYe...ature=youtu.be

  • #2
    Re: Baybots 2012 Table Run

    Nice bot and attachments! I liked the delivery of the viruses and bacteria to the sink.
    Thanks for sharing.

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    • #3
      Re: Baybots 2012 Table Run

      The extendable arm was a nice touch. Also shows a nice method of collecting the big fish and leaving the baby untouched. I didn't see very much use of reference marks for that final drive. Was that all odometry?

      (nice boat, too!)
      FIRST Tech Challenge Judge: 2010, Referee: 2017
      FIRST LEGO League Mentor, Instructor, and/or Referee/Head Referee since 2011
      FIRST Robotics Competition judge (Chairman's Award): 2014
      Dean says I'm an "Oompa Loompa of Science"

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      • #4
        Re: Baybots 2012 Table Run

        It is odometry - aided with wall following at the end, but the tight passage between between the sink and fence is protected by a piece of code that can detect a collision and make a driving correction if necessary - this example is plugged into the first mission in case the fence is hit on the way to the rat

        http://baybots2012.weebly.com/code.html


        soon this will all be in the past and we will be back to simple tubing!

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        • #5
          Re: Baybots 2012 Table Run

          Originally posted by baybots2012 View Post
          It is odometry - aided with wall following at the end, but the tight passage between between the sink and fence is protected by a piece of code that can detect a collision and make a driving correction if necessary...
          That's clever. I am going to show your bit of code to my team to help get them started on rotation sensors, which are something they never even considered in year 1. Thanks for posting!
          Twitter --- Facebook

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          • #6
            Re: Baybots 2012 Table Run

            Originally posted by baybots2012 View Post
            It is odometry - aided with wall following at the end, but the tight passage between between the sink and fence is protected by a piece of code that can detect a collision and make a driving correction if necessary - this example is plugged into the first mission in case the fence is hit on the way to the rat
            I noticed that the bot didn't clear the fence by very much. The wall follower wheels were a nice touch, too.

            That's a very clever piece of programming. Does it exit the first loop on either reaching the safe distance, or if sensor B stalls? (the text is a little blurry).

            The most advanced programmer on the team I'm mentoring used this same method of exiting a loop, just yesterday afternoon. His robot was rotating endlessly searching for an object that was near enough to push (Turn unlimited followed by a Wait block using "distance < threshold"). He ended up replacing the wait block with a "loop until logic" exit condition, with the two conditions being "distance < threshold", or "timer > 5 seconds". It's a very powerful technique.
            FIRST Tech Challenge Judge: 2010, Referee: 2017
            FIRST LEGO League Mentor, Instructor, and/or Referee/Head Referee since 2011
            FIRST Robotics Competition judge (Chairman's Award): 2014
            Dean says I'm an "Oompa Loompa of Science"

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            • #7
              Re: Baybots 2012 Table Run

              I see no reason not to do this for every move. Write up a nice Move MyBlock with a Stalled output plug.
              Attached Files

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              • #8
                Re: Baybots 2012 Table Run

                the loop will exit if a stall occurs or if a "safe distance" is reached.

                there has to be a better way to determine or signal which of these conditions occurred first other than "re-sampling" the rotation sensor - but what that might be remains a mystery to us.

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                • #9
                  Re: Baybots 2012 Table Run

                  Originally posted by baybots2012 View Post
                  the loop will exit if a stall occurs or if a "safe distance" is reached.

                  there has to be a better way to determine or signal which of these conditions occurred first other than "re-sampling" the rotation sensor - but what that might be remains a mystery to us.
                  A problem with looping on the two conditions is that the delay will cause you to always overshoot the duration. Choosing a short delay between consecutive reads minimizes this, but there will always be some variability in the resulting distance.

                  A solution is to separate stall detection from the move. You can use the standard Move block to control the move and run the stall detection in parallel. If you detect a stall condition you use the Reset block to abort the move.

                  If you want to stay with using the dual conditions you can do sampling using a variable and a timer. Inside the loop you do a switch based on the timer value. If the timer is greater than half a second or so you compare the current rotation sensor value to a value stored in the variable. If the difference is less than some threshold the motor stalled.
                  Attached Files
                  Last edited by Dean Hystad; 02-25-2012, 12:47 AM.

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                  • #10
                    Re: Baybots 2012 Table Run

                    thank you Dean. your advice and opinions, while sometimes unvarnished, are always direct and welcome.

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                    • #11
                      Four motor function with three motor prototype

                      Four motor function with three motor prototype

                      http://youtu.be/IWXTHZSjkcI

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                      • #12
                        Re: Baybots 2012 Table Run

                        great idea.. nice job baybots2012. it can save 1 motor.

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                        • #13
                          Re: Baybots 2012 Table Run

                          4 Motor function with 3 motors prototype II

                          http://www.youtube.com/watch?v=Njg-y...ature=youtu.be

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                          • #14
                            Re: Baybots 2012 Table Run

                            Great information. Thanks for sharing it

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