Beginner to Vex IQ and iqblocks - Help required autonomous - Accuracy and precision in driving and taking turns

Hello, we’re a new elementary team and having difficulty with our autonomous program. The kids understand the basic commands, they used the measurements etc and built a program(straight forward commands) to clear both the corrals, but oh boy! they have success may be 1 /20 runs. They have spent many weekends of 8-12+ hrs every day with very little success, they are pretty demotivated right now. We did some research and found out different ways to solve our problem such as PID and motor encodes. Came across the Caution tape’s videos. However, we have no idea how to incorporate any of this code to our existing program, because i don’t know how to code and the kids are pretty young 9-10 yr and being their first time they are having difficult time to understand. Could somebody help us, explain to move our drivetrain straight and take precise turns using some sample Pcontroler/PID? We need something simple because as I said we’re new to coding. We’re using Vex Code . Thank you all for your time and valuable inputs

Can you share any of your existing code and videos of your autonomous runs? For things like clearing the Corrals using complex code should not be necessary so maybe something else is wrong?
Are you using a gyro on your robot?


I think clearing the corral should not need any PID it anything of that sort. I made a quite consistent 65 point autonomous with only the built-in commands. Maybe share more information about your problem? Probably your code and a video of your autonomous routine would go a long way, as @calvc01 said.


Sorry i should have been more specific, i meant clearing the balls from corral and try to score in the high goal. They are able to get to the balls, but they can never make those precise turns to go back and shoot the balls consistently
I will take a video of the auto run and the snippet of the code and share it today after work. Thank you so much!

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Sorry i should have been more specific, i meant clearing the balls from corral and try to shoot it in the high goal. They are able to get to the balls, but they can never make those precise turns to go back and shoot the balls in the corral consistently.
I will take a video of the auto run and the snippet of the code and share it today after work. Thank you so much!

How many points are you trying to get?

  1. How many balls can you hold?
  2. What route are you following?
  3. Any gyro?
  4. Make sure you’re extremely particular when setting up the robot?
    One thing that helps is having parts on the back of your robot that you line up with holes in the field perimeter.
  5. Try ramming fully into the corner and then backing out?
  6. What’s your score goal?
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Thank you for your response and sorry for the late response, was kind of taking break from here due to hectic work. These are elementary kids but have put in many hours in auton, their robot can shoot balls to the high goal, so they don’t have a limit on how many balls they want to target. At this point they have written code for 82 points, but they have never been able to execute successfully 20-30% of the time consistently.

Running a program to clear the corral and score in the high goal is pretty hard. If they aren’t using a gyro and doing at least a P loop it’s just going to be really hard. The components need some help.

I’ve looked at the Caution Tape videos, and while I understand the concepts it’s a little above what most of my middle school students can do as well.

It seems like that’s not where the kids are, and that’s fine. Seems like their “unsuccessful” runs are going to go pretty well, and will score at least 34 points.

Would be a good time to maybe focus on driving and making sure that part of the competition goes well. That’s what they are going to be doing more than anything else at the tournament, right?

Yeah, I kind of agree with @sankeydd: Your kids seem pretty young to try a PID or anything that complex. I would suggest just trying to figure out a route where you can run into walls and corners to realign. I made a surprisingly consistent 65ish point program with nothing more than go forward x inches, turn right x degrees, etc, plus backing into a corner to align. (I think the most amazing part is that I made it from scratch the day before States and it got 61 points there: the best at the tournament.)

I explained in another place about backing into a corner using back 0.2 seconds and the like.


That is what my kids are doing as well, the straightforward command blocks. When things did not improve, to help them with their frustration I surfed here looking for suggestions and came across the PID principle which even i can’t understand, i mean i get the high level logic but don’t understand how to translate it to a code and make it work. So my kids tried using the caution tape’s code, since I could not mentor them on this further, they are back at their original program.

All I can really say is, I’m sorry they’re frustrated. As far as I know, programming is routinely inconsistent. The best option for you, I think, in terms of difficulty and effectiveness, is probably just to run into the wall as much as reasonably possible. I did that and it worked surprisingly well. I think if you and the ten-year-olds tried to make a PID loop with the amount of frustration and pressure already built up, you and they would just get frustrated.

I tried for about a full 9-hour day two days before States to make a PID loop and my plans and I were frustrated. The next day I set to work and made a normal program using regular commands plus backing into the wall, and I got it to 4 balls in the goal nearly every time. The rest was just clearing the corral and backing up to the goal again, which I finished at States the next day. My only problem was that I was running out of time; I was about 0.5 seconds away from 71 points.

I think your best bet is to realign with the wall periodically. I’m not sure if you’re aware of this, but you’re also allowed to pick up your robot in the middle of a run a start it again in a starting position, which basically means you only have to write half the code, because you just set it down again on the identical other half of the field.

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Thank you for your suggestions!
Yes, kids have 2 sets of code with 2 touch LED, so they are able to repeat the code on the other side by resetting the robot. I am not able to visualize ‘realign with the wall periodically/backing to the wall’ is it ok if i ask you to send me a video of your run or an example of realigning to the wall, i can show it to my kids. Thank you again for your support.


Yeah looks like to achieve high goal score they need some level of sophisticated programming so my kids went back to their basic code and hoping it will fetch them some points. They do focus on their driving but they are also much interested to learn how to program, unfortunately as a coach i am not able to cater to their needs but i am definitely looking to see if someone can have few sessions or classes with my team to teach them so they can use the learnings for the next season. I wish there was some way to reach out to the middle school teams who might be graduating to high school and they can mentor beginners such as mine.

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