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  • I had a heck of a time finding the referred to posts. I had to experiment around with different forum settings until I found the switch that displays the post #, unfortunately that conflicts with displaying the most recent posts on top.

    Most of the stuff I post is along the line of "The solution is left as an exercise for the reader." For the invert motor direction post the hidden case puts +1 on the wire exiting the block. Leaving the case empty should cause an error (and wouldn't work) because all cases in a switch block should provide values for all wires exiting the block. What is the value in a wire with no source? The software may provide a "cover your bottom" value (probably 0), but I've never tested for that.

    For most wheels you cannot directly measure track. We cannot predict the location of the wheel contact patch. What I do is guess by measuring from the outside of the left wheel to the inside of the right. This gives you the same number as "center to center", but is easier to measure. Then I command the robot to turn 10 revolutions and adjust the value accordingly.

    A little while back I wrote a program that calculated all the constants for my robot. First you push the robot forward and press a button. This tells the robot if the motors are reversed or not. Next you place the robot 36" from a wall and press a button. The robot drives forward until it stalls and uses the rotation sensor feedback to calculate wheel circumference. Next the robot spins in place for 10 revolutions (using gyro sensor feedback) and calculates robot track. Finally the robot moves the attachment motors until they stall. All the measurements are saved in files. These files are read and the values used in move and turn blocks. As long as the sensors/motors are connected to the same ports I can write a mission on any robot and run it on any other robot and the results are really close. Would this provide any benefit for FLL? Probably not.
    Last edited by Dean Hystad; 01-25-2019, 01:59 PM.

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    • Originally posted by Dean Hystad View Post
      I had a heck of a time finding the referred to posts. I had to experiment around with different forum settings until I found the switch that displays the post #, unfortunately that conflicts with displaying the most recent posts on top.

      Most of the stuff I post is along the line of "The solution is left as an exercise for the reader." For the invert motor direction post the hidden case puts +1 on the wire exiting the block. Leaving the case empty should cause an error (and wouldn't work) because all cases in a switch block should provide values for all wires exiting the block. What is the value in a wire with no source? The software may provide a "cover your bottom" value (probably 0), but I've never tested for that.

      For most wheels you cannot directly measure track. We cannot predict the location of the wheel contact patch. What I do is guess by measuring from the outside of the left wheel to the inside of the right. This gives you the same number as "center to center", but is easier to measure. Then I command the robot to turn 10 revolutions and adjust the value accordingly.

      A little while back I wrote a program that calculated all the constants for my robot. First you push the robot forward and press a button. This tells the robot if the motors are reversed or not. Next you place the robot 36" from a wall and press a button. The robot drives forward until it stalls and uses the rotation sensor feedback to calculate wheel circumference. Next the robot spins in place for 10 revolutions (using gyro sensor feedback) and calculates robot track. Finally the robot moves the attachment motors until they stall. All the measurements are saved in files. These files are read and the values used in move and turn blocks. As long as the sensors/motors are connected to the same ports I can write a mission on any robot and run it on any other robot and the results are really close. Would this provide any benefit for FLL? Probably not.
      Thanks so much. I nearly attached the images I was referencing, but felt sure it'd be overkill. Sorry for the fire drill.
      _____________________
      Bryan H
      Engineering & Robotics Teacher
      HEB Independent School District
      Bedford, TX

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      • Hi.I need help.i couldnt find my hi technic color sensor block in my port dock in the labview.but it exists in my ev3 port view please i need this asap

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        • Originally posted by Mr Builder View Post
          Hi.I need help.i couldnt find my hi technic color sensor block in my port dock in the labview.but it exists in my ev3 port view please i need this asap
          Having a sensor block available in EV3 has nothing to do with the sensor having a .vi in LabVIEW. You will have to find a .vi file for your sensor (HiTechnic may have it available on their website) and copy it into your project.

          Start looking here.

          http://www.mindsensors.com/blog/how-...indstorms-2015

          Comment


          • Originally posted by Dean Hystad View Post

            Having a sensor block available in EV3 has nothing to do with the sensor having a .vi in LabVIEW. You will have to find a .vi file for your sensor (HiTechnic may have it available on their website) and copy it into your project.

            Start looking here.

            http://www.mindsensors.com/blog/how-...indstorms-2015
            Thanks for the reply.I'm still stuck on how to use the Hi Technic Color Sensor on my robot.The photos that I uploaded is what the Hi Technic website has ordered me to download in order use the Hi Technic Color Sensor.I have downloaded a .ev3b file that I am using to import the sensor command block into my LEGO MINDSTORM EV3 Home Edition.However,when I plugged the Hi Technic Color Sensor into my ev3,my programming platform do not detect the sensor.I am truly if this wasting your time because I am still new in this area of programming.Your help is much appreciated.If I need anything more I will ask directly through the private message chat.

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            • You need to install the sensor block in the EV3 programming environment before use. Here's a link on how to do that:

              http://www.mindsensors.com/content/1...-blocks-in-ev3

              Here's a youtube video of someone actually installing and using the hithechnic color sensor.

              https://www.bing.com/videos/search?q...C422&FORM=VIRE

              After you do this you should see programming blocks for the sensor. I don't have any 3rd party sensors, so I don't know if they show up on sensor view. I could not find a video that showed using port view to see what values the sensor returns.
              Last edited by Dean Hystad; 05-09-2019, 03:40 PM.

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              • Hello Dean,I am new in this robotics competition.Is there any tips in building football/soccer ev3 robot?
                Your help is much appreciated.

                Comment


                • Originally posted by Mr Builder View Post
                  Hello Dean,I am new in this robotics competition.Is there any tips in building football/soccer ev3 robot?
                  Your help is much appreciated.
                  There are some instructions on building and programming EV3 robots that play soccer in this document
                  https://robocupjunior.org.au/sites/d...e%20Tris10.pdf

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