Mission Possible C

[Trumpsta]

Notice that a match is lit by friction. The ETL does not claim a mechanical>chemical transfer, what is actually happening, but instead claims mechanical>thermal. I see this as an application of the "black box" principle - what happens "inside" something you didn't make cannot be counted as a transfer. The match has an input (friction - mechanical) and an output (heat - thermal) or (light - EM spectrum).

interesting, i saw this as an application of "a single action must contribute to only one sscoreable transfer" the action being the input of striking the match and the output being what you harness, which would be the thermal (or ems). it wouldnt matter what happens inbetween (the chemical) not because it doesnt happen but because you arent taking advantage of the chemical to interface with something else. so, it's like each energy form is associated with one component; the mechanical is associated with whatever the match is striking against, the thermal is associated with the match, etc.

also on the etl on soinc, the title is "task sequence list" should we change this to "energy transfer list" chalkers? so it'd be "(tournament) Energy Transfer List"

[olympiaddict]

The importance of what is posted on the example ETL is definite, that's a good point about how the match is scored there.

However I have a problem with this. Rule 4b says "an energy transfer can receive points when it directly transfers from one Basic Energy Form to a different Basic Energy Form."
When a match is struck, the transfers I see are
M-> t Friction between head and striker
T -> c Heat from friction is activation energy for chem reaction of combustion
C -> t Matchstick burns and releases heat

I can't agree that that is converting "directly"- there is the chemical intermediate step.

Thus I see a few possibilities.

1) consider rule 4: "a single action must contribute to only one scorable transfer". Perhaps whoever wrote the sample ETL interpreted striking a match as one "action" and therefore only one conversion is scoreable- the initial mech -> therm of friction. This seems semi plausible since no non-scoreable transfers are listed on the sample ETL. Possibly they are just to be ignored. (I think the "ignoring" thing is unlikely though.)

2) whoever made the sample ETL just made a mistake and didn't fully consider the "directly transfers" rule when writing this document. This is possible, after all it is labeled "task sequence list", a remnant of mission possible B from recent years, instead of "energy transfer list", so it's possible another error was made.

3) I'm missing something, maybe you guys see something I don't.

I just think it's unlikely that the version of the "black box rule" in which any commercial component can be viewed as only input-output is actually a rule- nothing indicates that in the written rules. Plus, one could home-make matches or something that raises the same questions , and then would two devices that are functionally the same be scored differently?

[Trumpsta]

what exactly constitutes an "action"? it seems to imply some kind of movement, best seen in a change in location. under one action one transfer, perhaps the to and from chemical transfers in a match dont count because it happens in the same place? same for incandescent...

[Robotica]

All of these interpretations are leaving us builders/competitors scratching our heads. How are we suposed to know how an event supervisor is going to interpet these transfers. We have been to 4 invitationals with regionals approaching soon, and every event was run different. One event supervisor dissalowed a thermal switch because it was not a visable action, yet no one else ever questioned it.

[torqueburner]

All of these interpretations are leaving us builders/competitors scratching our heads. How are we suposed to know how an event supervisor is going to interpet these transfers. We have been to 4 invitationals with regionals approaching soon, and every event was run different. One event supervisor dissalowed a thermal switch because it was not a visable action, yet no one else ever questioned it.

I've been a Mission event supervisor several times in past years, in both B and C division, at invitationals and at our Regional tournament. But they were previously "task oriented" Missions, so most of the issues currently being discussed didn't apply. This year, I have once again agreed to supervise Mission. In an attempt to reduce confusion, I wrote a short document explaining how I interpret some of the rules and other issues that are currently under debate on this forum. This was emailed to all of the participating schools, and I invited the students to send me their ETLs in advance of the submission deadline. I offered to look them over, and to comment on anything that I might have an issue with on the day of the competition. Most schools took me up on this, and we managed to iron out our differences of interpretation. There were very few problems on the day of the the competition (other than the usual Mission problems ), no resulting disappointment, no hard feelings.

I'll do the same at our Regional in March, with a caution to all advancing teams that the State supervisor may have different ideas. A good point that has been made numerous times is that the event supervisor's interpretation is paramount. Every Mission supervisor has to judge your device with the same set of rules that you use to build it, and we can see that some of those rules are subject to more than one interpretation, one often as valid as another. As an event supervisor I know that the last thing I want is a surprise on competition day that requires me to make a quick judgement. So in the absence of further clarifications or FAQs that might elucidate some of these things, contacting your upcoming event supervisor is probably the best thing you can do.

[themaker]

Does anyone have any idea on how to run an infrared led directly off a battery? I have look on other websites and it seems like you will always need a resistor in the circuit, . Otherwise, the current from the battery would be too big (even from a 1.5 volt). Resistors aren't listed as a legal electrical component though. Does the fact that leds are allowed imply that resistors are allowed? Otherwise it would seem like it would be impossible to use leds anyways.

[olympiaddict]

That was what I thought originally as well, and I don't see the logic behind disallowing resistors. But anyways, I was able to run a 20mA visible light LED with a voltage drop of 2.4 v off of two 1.5v AA alkaline batteries in series.
I think you just have to see what works since in the real world LED's are not used like this.

[iwonder]

Yeah, in reality LEDs are considered current driven devices, so the brightness is based on current (thus the current limiting resistor) but in this case it's probably safe to use 2 AA's or AAA's to run them, just don't go over 6-9v or you'll find a tiny shard of plastic embedded on the other side of the room and hear a nice little pop.

[Uncle Fester]

Three solutions, some more elegant than others:

One, just use AAA's, as their low current sourcing ability and your short-time use should prevnt damage.

Two, use a blue or white LED. They have a much higher forward voltage drop, like 4-5 volts.

Three, find something of resistance that's not a resistor. A thin length of brass, a pencil split mengthwise with two gator clips on tghe exposed lead completing the circuit.

Bt the way, Kudos for knowing how LEDs actually work.

[chalker]

Three solutions, some more elegant than others:

One, just use AAA's, as their low current sourcing ability and your short-time use should prevnt damage.

Two, use a blue or white LED. They have a much higher forward voltage drop, like 4-5 volts.

Three, find something of resistance that's not a resistor. A thin length of brass, a pencil split mengthwise with two gator clips on tghe exposed lead completing the circuit.

Bt the way, Kudos for knowing how LEDs actually work.

4. get an LED with an integrated resistor (they aren't as common as 'normal LEDs', but aren't too hard to find
5. wait for us to officially issue a clarification in the near future that might clear this up (hint hint;)

As always, this isn't the place for official statements or clarifications though......