Which sensors are the most effective.
My team currently uses:
Potentiometer
Encoder
Gyro
Bumper Sensor
Are there any other other sensors that could be useful for this year’s competition?
Yes, literally all are useful
Have you used all of them?
I don’t see use for sonar sensors.
But line sensor can work.
Sonars can be used to sensw distance from the wall, or other robots if your so inclined i have used all of them, theyre all useful
I like button sensors too. Much more durable than a limit switch
But with sonars, what is the possible advantage of sensing another robot in a competition. And wouldn’t it sense all objects and not the one I want it to go to?
True. But limit sensors are made for pressure sensitive touches.
It is generally easier to activate them.
We used to run auto in nbn that ran into other robots to throw off their autos, we used sonar for it. And every other sensor also tracks everything so… they have their uses
Just a word of advice: DON’T USE IME’S!!! Use the red shaft encoders instead; they’re soooo much better.
That is what I use 
Yes it can be used for that
True, but I would rather go through the extra difficulty of getting the button sensor to activate than risk a limit switch breaking mid-match
Depends on placement of the sensor
3116 had a great side roller bot for starstruck that used button sensors very effectively with no issues in the same way we used a limit switch
We only use button sensors usually for positioning the bot if it bumps into a wall.
Limit switches are useful only if placed correctly
There’s no real advantage of sensing another robot during the driver period, but during the autonomous period you could make your robot avoid other robots or potentially run into them like @9065_parker said:
We used sonars to sense how far away from the wall we were in Starstruck. It worked really well, we beat 2 of the best teams in the state with that auton.
Quad Encoders, Gyro, Bump Sensors, Potentiometers.
After Toss Up, I have swore off IMEs. Good lord I wanted to punt the VEX U robots into the stands after those things just failed to respond.
This was my year to swear off IMEs! From the first tournament to the very last, they were just a crap shoot on whether they would operate as programmed. So frustrating. I think the parents were starting to think there was something wrong with me as a coach because I couldn’t help my kids get their robot to act right! When we take the robots apart, we are taking every IME off every motor and putting them somewhere way far away!! My favorite expression for my team is “well, the program is doing exactly what you told it to do!” and that’s just really not the case with IMEs - they act erratically and there’s no explaining why!
That being said, we use the same sensors as Oscar - quad encoders, bump sensor, potentiometer. We bought gyros in the off season and have been experimenting with them and will probably incorporate them if they prove to be reliable.
I’ve found that the students frequently blame things other than their own misunderstanding and lack of experience for things that go wrong. (“Battery voodoo” is how we named one set of incorrect attribution.) So, when one of them starts telling me “this part is going crazy” or “the code won’t work if you hook that up” I usually think they haven’t done enough work to be sure. So, we did some work on these. We were able to show autonomous failed 3 out of 5 times in one series of tests with the IME cabled in. Remove the cable, and autonomous ran 5 out 5 times. We did this on two separate robots on different fields on different days with similar statistics. (2 out of 5 failures on the second robot, different day.) Note that they weren’t using the IMEs, they just plugged them in. So, not voodoo, and not for me.
@jpearman describes the reset-on-static-pulse nature of the I2C chip in the IMEs, (IME - Technical description and software workarounds - Technical Discussion - VEX Forum) so it’s not without technical backing.
Note that several of the EC3 teams used IMEs in their Startstruck robots, sometimes to good effect. However, nobody was immune to the reset effect, and everybody knew their one minute autonomous just might not work. It was a bigger problem in the colder drier winter months than it was at the end of the season. Still, I wouldn’t personally recommend using the IMEs.
Be sure to mount the gyro on the vex rubber links or suspended on rubber bands. If you use a solid connnection to secure the gyro the vibrations from motor operation can cause significant drift error. Also, you have to scale the output of your gyro. There is a variation between devices in the reported angle turned. Once you put that in your calibration, these devices seem to work pretty well.