using the rules of this years game as who know what rules we will have for 04, what type of communication /sensors do you think is ok? FIRST says no wireless communication is allowed, but let you use some items. I mean, you can use optical sensors to get information about your environment. those obviously do not operate with wires. instead they are using readily available information and processing it. I’m assuming that the reason they are ok is because they are a passive devices? so would other passive devices be allowed? theoretically, if gps would reach inside a building and you could make a receiver for under 200, could you use it? you aren’t generating any signals, mearly reading those that already exist. the reason im wondering is because i have a great idea for next year, but it is highly involved and complex. in order to do it, i would need to start researching general info so my team and I would be ready by build season. However, if it would not be legal, I dont want to waste everyones time!
I do not know the answer that you seek, but also remember the accuracy needed to have a gps system usable with in such a small space, plus the $400 electronics price limit.
Other than the optical sensors, you cannot use any powered switches. You can use electronics components Up to $200 (U.S.) worth from Future FAI or Digi-Key. No individual part cost > $100.
no, its not gps. that was an example. you both are kinda of mising the point, which is “are passive sensors allowed?” ie, they may be reading input/signals, but have no control over the input and or signal being sent (such as gps, gps devices only recieve a signal being sent by another device, they dont communicate back, nor do they have any control of the incoming signal ).
GPS (atleast the commercial versions) use very weak signals and usually require an unobstructed view of the sky to lock onto the various satelites. Even so, commercial accuracy is not all too good (not sure of the exact number, but I found this here:
Improving the GPS
Since 1990, when the U.S. government made available the Global Positioning System (GPS), there have been calls for correcting the built-in error that the Department of Defense (DoD) required when the system was launched. The error, called Selective Availability (SA), was installed by the request of the DoD to deter the system from being utilized by terrorists or other potential enemies. The DoD intentionally varies the timing mechanisms aboard each GPS satellite in order to limit the accuracy of the system. Without SA the commercial GPS accuracy would be about 20 meters. With SA, the system’s accuracy can degrade by as much as 100 meters. There have been continued calls for removal of SA and the government has stated it will phase it out over the next few years. However, in the meantime, users of GPS have found methods for overcoming the error. Entrepreneurs have improved GPS accuracy by using differential techniques to measure and correct the artificial error. And while the removal of SA would increase the accuracy of the system, at this time many users desire even greater accuracy. Thus, many GPS users say the need now is for the development of better differential techniques with or without the presence of SA.
The point of this is that you’re not going to get anything more accurate than a few (dozen) meters - inside a building, even if you do get a signal, it would be a few hundred meters. For travelling around town, that would fine. For travelling around a FIRST field, it’s completely useless.
As for other things, I don’t know what else you could use them for. The only use I can possibly imagine (without broadcasting anything back) would be to create some kind of secondary remote control. This of course brings a whole different set of rules into question, mainly the ones about participation from the audience and how it’s frowned upon.
Aside from GPS (which turns out to be useless for our purposes), I can’t really think of any reason that is legal or any useful purpose. What specifically did you have in mind?
Speculation:
Since GPS signals are blocked by buildings, anyone think it’s possible to create a ‘relative’ gps system - like set up transmitters around the arena and create some triangulation technique to get relative motion from those?
Speculation 2: Actually, it would be 1000x easier to do what WildStang did this year to keep track of relative motion.
If I am following your thinking here, this is what I would expect next year…
Auto mode stays in for 15 seconds, BUT…
Teams that can avoid objects and/or other robots will gain bonus points or multipliers. OR
Teams that can maneuver a small maze or make it to a prescribed area in auto mode get bonus points or multipliers. OR
For a real difficult twist, auto mode in engaged at random and the robot has to seek out a target area for bonus points or multiplier. (sort of like musical chairs, find a seat.)
Any of these game additions require additional sensors, perhaps requiring the raising of the single component cost limit. Ultrasonic detectors, sound seekers, reflection seekers, bar code readers all are possibilities.
I am assuming this is illegal: You set up two or three radio transmitters, on different frequencies (maybe not radio, but something that wouldn’t interfere with the OI stuff) and have the bot able to read each on, and compute a distance based on signal strength. Having told the bot where the transmitters would be, then the robot would know its location with absolutely no error due to wheel slippage or inaccurate sensors . . .
However, I am assuming that the transmitters would be illegal,
what he is asking is can you have something on the robot that reads some existing feild without creating or modifying it.
Hell, thats what a compass does, I know there was a team that read the earth’s magnetic feild last year or something.
So maybe, yes, but I wouldn’t push your luck and create a feild of somesort over the playing feild. I doubt GPS is feasible, but you could probably use a compass.
*Originally posted by Frank(Aflak) *
**I am assuming this is illegal: You set up two or three radio transmitters, on different frequencies (maybe not radio, but something that wouldn’t interfere with the OI stuff) and have the bot able to read each on, and compute a distance based on signal strength. Having told the bot where the transmitters would be, then the robot would know its location with absolutely no error due to wheel slippage or inaccurate sensors . . .
However, I am assuming that the transmitters would be illegal… **
exactly, setting up transmitters would be illegal. nor do I want to set any other devices up to generate any fields. I could easily tell everyone what I’m thinking, but a lot of FIRST is innovation and I want to see if other teams can come up with this idea on their own. However, I’ll give you all a hint: what signal is readily avialible at every competition that could be used in such a way as to be useful to your robot?
*Originally posted by Frank(Aflak) *
**I am assuming this is illegal: You set up two or three radio transmitters, on different frequencies
However, I am assuming that the transmitters would be illegal, **
Frank,
No that would not be illegal. The FCC has some pretty soft rules concerning low power transmitters. Stuff under 1 watt output and typical 100mW outputs do not need licensing as long as they don’t interfere with critical services, i.e. heart monitors and military radios. There is one problem, field strength is affected by objects in the pattern. Moving robots, judges and referees, cameras and drive team will all affect how the individual transmitters will be received. That does not rule out Radio Direction Finding or RDF. That would be a pretty cool thing and something we have been looking into this year as an addition to auto mode sensors. As such, the addition of a transmitter is illegal under FIRST rules but there are many possibilities.
yah, by illegal, I think he meant in terms of FIRST’s rules. I know I was! it may be all well and good in the legal goverment sense, but if FIRST won’t allow it, whats the point (for competition)?
The GPS I have takes a minute or two or four to lock in the open, and never if in the vicinity of reflecting surfaces (like large buildings).
GPS dithering was removed several years back, but the resolution of ordinary equipment is metre, not centimetres, Surveyors have equipment that measures the phase of the received carriers, to calculate to millimetres.
A setup that had three transmitting stations in the field corners similar to the VOR stations used for air navigation, which allow the receiver to determine the course to the transmitter in degrees true, would be neat - and if First set them up, everyone could use it, and position would not be a problem. They work like a flashlight rotating round and round at constant speed, casting a horizontal beam as it does. In effect, another light flashes as the beam goes past true north. You start timing when you see the flash, and stop when you see the beam. Three receivers would not be expensive, but the 1 degree phase-shifting antenna for the transmitter might be, as well as having 12 of them at finals.
If you have seen little round buildings wearing white conical witches hats with vertical spikes around the brim, you have seen a VHF Omni Range statoin. We used to see one beside I-5 (in Ohio ?). Use two or three to determine your position. In flying an aircraft, the transmitter locations are on the map, and are thus a known quantity.
Perhaps coloured lights could work. As an added advantage, your heading could be determined. using any one of the three. You’d have to be line of sight to at least two. Wouldn’t that be fun programming ?