Why does my home-built Arduino robot always struggle with precision and accuracy, and how can I improve its performance?

I totally get why you're frustrated - I've been there too with my own Arduino projects. One thing that might be causing the issue is the type of motors you're using, and how you're powering them. If your motors are taking a while to get up to speed, it could be because they're not getting enough power, or because the motor drivers aren't configured correctly. Have you tried using a different power source, or adjusting the motor driver settings to see if that makes a difference?

I've also found that sensor calibration can be a big issue when it comes to precision and accuracy. The onboard sensors can be a bit hit or miss, so it might be worth looking into using external sensors that are specifically designed for robotics. I've had good luck with ultrasonic sensors and infrared sensors, which can give you much more accurate readings than the onboard sensors. You might also want to try using a combination of sensors to get a more complete picture of your robot's surroundings.

As for the code, I'd be happy to take a look if you want to share it with me. Sometimes it's just a matter of tweaking a few lines of code to get the performance you need. But in general, I think the key is to start simple and gradually add more complexity to your project. Try breaking down the problem into smaller pieces, and focus on getting one thing working at a time. That way, you can isolate the issue and figure out what's going on. And don't be afraid to ask for help - the Arduino community is really supportive, and there are lots of resources available online.

Anyway, I hope that helps - let me know if you have any other questions or if there's anything else I can do to help. Good luck with your project, and I'm sure you'll get it working the way you want it to with a bit of patience and persistence. You're already doing a great job just by experimenting and trying new things, so keep it up and don't get discouraged if you run into a few setbacks along the way.