Recommended Sensors

[Clem1640]

Originally Posted by adciv

The main question comes down to what do you want to sense, and then how do you do that.

That's the key question. What do you want to sense?

For our swerve drive, we need to know absolute angle: 360 degrees and stop-less. We use BI Technologies Magnepot Hall Effect Potentiometer Part # 6127V1A360L.5FS to do this. The analog sensor works very well and is ~$11 ea.

[Tyler2517]

It depends a lot on what you are doing. Along with accurate do you need to be.

For instance when we started redesigning out swerve drive we sat down and listed all of the sensors we would want / have to use.
1. Steering encoder (absolute ,continuous)
2. Drive encoder (quadrature)
3. Gyro for field based control.
4. Limit switch to auto home swerve.

[adciv]

To give a bit more background, our 2012 Rebound Rumble robot was... interesting. We used the following sensors:

Axis M11 Camerax2
Hall effect x1
Proximity Sensor x3
Light/Dark sensor x1
IR Prox Switch x1 (from LogoMotion)
Limit Switch x1
Encoder x2
Absolute Encoder x1 (analog)
Ultrasonic Rangefinder x2

I think we maxed out all the DIO on the sidecare that year, and I'm pretty sure I'm missing at least some sensors.

[Gregor]

Originally Posted by adciv

To give a bit more background, our 2012 Rebound Rumble robot was... interesting. We used the following sensors:

Axis M11 Camerax2
Hall effect x1
Proximity Sensor x3
Light/Dark sensor x1
IR Prox Switch x1 (from LogoMotion)
Limit Switch x1
Encoder x2
Absolute Encoder x1 (analog)
Ultrasonic Rangefinder x2

I think we maxed out all the DIO on the sidecare that year, and I'm pretty sure I'm missing at least some sensors.

Sounds awesome! Lets try and guess what they were for.

Axis M11 Camerax2
Vision tracking and a ball pickup camera.

Hall effect x1
Shooter feedback

Proximity Sensor x3
Ball sensors?

Light/Dark sensor x1
?

IR Prox Switch x1 (from LogoMotion)
?

Limit Switch x1
Turret soft stop

Encoder x2
Drivetrain

Absolute Encoder x1 (analog)
Turret feedback

Ultrasonic Rangefinder x2
?

[Hugh Meyer]

Here is a link to a sensor presentation I have done at worlds in 2013 and Purdue. It shows several types and explains how to wire them.

http://rar.meyermat.net/workshops/sensors/index.html

-Hugh

[adciv]

Originally Posted by Gregor

Sounds awesome! Lets try and guess what they were for.?

Axis M11 Camerax2
Vision tracking and a ball pickup camera.
- Distance/angle to Target using binocular vision. Ball Pickup is something we're looking at adding now that we have an example to work from. We used this system as (at the time) it provided better accuracy & noise rejection over using one.

Hall effect x1
Shooter feedback
- Correct

Proximity Sensor x3
Ball sensors?
- Correct. We used this for managing the balls in the robot. We maintained positive control & position knowlege over all three at all times through the use of a state machine.

Light/Dark sensor x1
?
- Used for telling us when our turrent was in the home position.

IR Prox Switch x1 (from LogoMotion)
?
- We used this at the front of the ball intake to let us know when a new ball was coming in. The proximity sensors were further up the system, and with the three ball limit we wanted to ensure we never possessed a fourth.

Limit Switch x1
Turret soft stop
- We had a "spear" that would come down for lowering the bridge. It was used as a softstop for that.

Encoder x2
Drivetrain
- Correct.

Absolute Encoder x1 (analog)
Turret feedback
- Correct, although we would loop it and had to add code which would note this. Our turret had a range of about 3 full encoder revolutions.

Ultrasonic Rangefinder x2
- Ball Detection.