What sensors do your teams use

[gerthworm]

Originally Posted by Steven Smith

AKA, in addition to WHAT to use, do you feel there are adequate resources on HOW/WHY to use sensors, that could be addressed by linking existing content or creating new content specific to FRC?

I've seen a number of resources online of various qualities, but it would be nice to see a single published whitepaper that describes how to design a robot sensing system from top to bottom.

Challenges with such a document:

• Keeping it up to date with changing technologies and parts availability.
• Satisfying a large range of audiences.

I'd expect some mentors or students don't want to think about sensing system design much, and just need a quick answer as to "what should I use for situation XYZ". Others will have this design experience, and just aren't familiar with what's commonly used for FRC...

Perhaps a community-maintained wiki for this (and other topics) is an option? I haven't seen one yet, although I haven't looked very hard either...

EDIT: After a brief amount of searching, I came across https://firstwiki.github.io/wiki/tech , but it looks like there is plenty of work to be done still.

[marshall]

We use students as limit switches... the robot runs into them and they let us know about it. Decent feedback but a little slow and if they get hit too hard then they stop working sometimes. The good thing is we seem to have a never ending supply of them for replacements.

[seg9585]

Originally Posted by marshall

We use students as limit switches... the robot runs into them and they let us know about it. Decent feedback but a little slow and if they get hit too hard then they stop working sometimes. The good thing is we seem to have a never ending supply of them for replacements.

Same here! We have some good video demos of using our student limit switches in autonomous mode:
https://www.youtube.com/watch?v=WumkMeRE6Iw

Seriously though, this year Team 4276 used the following sensors:

Optical encoders (drive)
LIDAR (drive, tower distance)
Gyro/Accelerometer (rotation and inertial distance measurement)
Hall Effect Switch (arm position reset)
Hall Effect Counter (gear tooth sensor -- shooter wheel sped control)
Rotary Encoder (Arm position)
USB Camera (Telemetry/Drive Vision)
2nd USB Camera (Autonomous target detection)
Vex Pushbutton Switch (intake ball detection)

[KJaget]

Originally Posted by marshall

We use students as limit switches... the robot runs into them and they let us know about it. Decent feedback but a little slow and if they get hit too hard then they stop working sometimes. The good thing is we seem to have a never ending supply of them for replacements.

As I remember our programming team also used the lab wall as a limit switch. Good thing our school's facilities guys are good with sheetrock.

Our actual list from this year :

line break sensors
lots of encoders (wheels and turret)
Stereolabs ZED depth camera

Probably missing something, but those are the major ones.

[snekiam]

We try not to use students or our build space as a limit switch; wouldn't want to damage the robot.

[Hitchhiker 42]

Our robot this year had the following sensors:

• 2 Optical Encoders for our Drivetrain*
• 2 Magnetic Encoders for our flywheel shooter
• Potentiometer for our actuating wedges
• Gyro
• 2 Cameras**

*In the offseason, we switched those out for magnetic encoders because one optical encoder never seemed to work (despite switching everything out from shaft to port.

**We got vision working in the offseason

[GeeTwo]

Originally Posted by snekiam

We try not to use students or our build space as a limit switch; wouldn't want to damage the robot.

Then how do you train your pit crew?

[snekiam]

Originally Posted by GeeTwo

Then how do you train your pit crew?

I said try not to, not don't. Don't worry, pit crew gets plenty of training