Relay to control 2 outputs

[Micah Chetrit]

Oh, I didn't know about that.
what specifically is forbidden? Can I wire the leds and put them in a tube (therefore just creating a part), but not wire it to a relay? or is making custom parts before season not legal?

[Travis Hoffman]

Originally Posted by Micah Chetrit

Oh, I didn't know about that.
what specifically is forbidden? Can I wire the leds and put them in a tube (therefore just creating a part), but not wire it to a relay? or is making custom parts before season not legal?

The latter case is true. Until the rules change, you cannot fabricate custom parts or construct custom assemblies for your official FRC robot prior to the start of the season. This is one of the core tenets of the FRC program - every team must engineer their robot within the same time window.

[Micah Chetrit]

Thank you for pointing that out. I guess I only have to make one set this summer then.

[Al Skierkiewicz]

Micah,
It is also possible that this wiring method would be illegal during next year's game and rules. I would hope that the GDC allows teams to use this method but you never know for sure. As stated the Spike is capable of switching either or both outputs between high and low states. The manual for the Spike explains this.

[Hugh Meyer]

Micah,

If you connect them to a Jaguar or Victor you could dim them. With different colors that could give you some interesting effects. You would need to put the LEDs in series to be able to tolerate the 12 volts...maybe 6 LEDs and a current limiting resistor. Just an idea...

-Hugh

[slijin]

Just as a note, what Travis said is perfectly true; any design done preseason is not legal for use during competition. However, if the design is modified (i.e. improved or optimized during competition) for the robot, then it is indeed legal.

[Warlord]

Although it is worth noting that given that this seems to be more decorative than functional - designing a whole drive train in the offseason is one thing, designing some pretty lights is something else entirely. I wouldn't worry too much about breaking the intent of the "6 weeks" thing.

[Steve Warner]

I don't have the latest version of the C++ WpiLib source code available to look at right now, but I don't think it allows both relay outputs to be turned on at the same time. Could someone explain why the Relay class was written this way and if it can be changed for the next library release.

[Ether]

Originally Posted by Steve Warner

I don't have the latest version of the C++ WpiLib source code available to look at right now

Whenever you have access to the web, V20110203rev2259 is available online for browsing.

The only stated differences from V20110203rev2262 are:
1. A NetConsole error in the cRIO that under some circumstances corrupt memory in the cRIO.
2. Fixed an error with the ADXL345 I2C accelerometer.
3. Fixed an error with allocation tracking in the Counter class.

[Steve Warner]

Thanks Ether. So in Relay::Set there is no way for the kOn case to set both outputs true. I think this is something that could be easily fixed.

[slijin]

To my memory, I believe controlling the 4 states of a Spike involves splicing together two outputs into the Spike input, though I could be wrong.

[Ether]

Originally Posted by slijin

To my memory, I believe controlling the 4 states of a Spike involves splicing together two outputs into the Spike input, though I could be wrong.

http://content.vexrobotics.com/docs/...uide-sep05.pdf

The White input (0/1) controls the M+ output (GND/+12v).

The Red input (0/1) controls the M- output (GND/+12v).

Thus, the Spike can drive a motor forward, reverse, or brake (no coast).

or

Drive two solenoids (or LEDs, etc) independently.

[Micah Chetrit]

Originally Posted by Hugh Meyer

Micah,

If you connect them to a Jaguar or Victor you could dim them. With different colors that could give you some interesting effects. You would need to put the LEDs in series to be able to tolerate the 12 volts...maybe 6 LEDs and a current limiting resistor. Just an idea...

-Hugh

Thanks for the Jag Idea, it sounds like a great idea. I was going to use team color LEDs though, so I am not going to lay too much with colors.

I was planning to put them in parallel however and use a Zenner Diode to regulate the voltage, simply because a 6 led chain isn't very long. I Have not tested the idea yet. I have never used Zenner Diodes before, Any opinion/experience with it? Other ideas?

[Ether]

Originally Posted by Micah Chetrit

I was planning to put them in parallel however and use a Zenner Diode to regulate the voltage, simply because a 6 led chain isn't very long.

You can make the chain as long as you like.

I have never used Zenner Diodes before, Any opinion/experience with it?

You didn't mention a resistor. Could you post a sketch showing how you plan to use the Zener to regulate the voltage to the LEDs?

[Micah Chetrit]

Originally Posted by Ether

You can make the chain as long as you like.

I didn't think about it that way before.

I believe I attached a basic drawing of my idea. I might have the directions of the diodes backwards, I don't really do any work in schematics.

Please bear with me, I am still not very experienced.