Thanks!
Color Sensors and Ultrasonic sensors are really fragile and our school didn’t have any that worked so haven’t been able to test much . We did get a new color sensor before the UK nationals but I’m pretty sure that it was broken or very inaccurate too as it was just giving random values and definitely couldn’t detect the difference between black and white. I’m also guessing they would be quite hard to use accurately as they would change according to outside environment so you may have to make some kind of calibration program to use effectively
We only use a gyro sensor which we calibrate to factory precision (thanks to this forum post) at the start of every code to minimize zero level drift. To create 100 percent accurate turnings we used a PD loop for the gyro as although you can predict inertia and make angles less , if you want to get tit accurate at a very high speed the only way (i think ) was some form of deceleration