Computer Boxes

[Hamley]

This is a idea i had and it prob has been though of before.
But is it possible to write a computer programe to act like a box. You would hook the reels into a thing you attach to a USB port. It would be cool because you would only have to modified the programe each time a new ruling came out, and it would be cheaper in the long run.

[telkanuru]

I can see the FIE seisuring as we speak.

I think the parallel port would be more appropreate. Actually, I think such a system would be relatively easy to create.

[DHCJr]

It has been done both with a PC and I even saw one that used an old Atari game computer.

[neevel]

Problem is, what happens when the laptop you're running it on gets whacked in the screen with an errant blade or knocked off of the table (this WILL happen eventually). An Eigetek, for example, will come through either without much more than a scuff mark to the case-- unless you're going to spend a chunk for something like a Panasonic Toughbook, a laptop won't take quite so kindly to such abuse. At $350-$400, Eigertek or Favero boxes cost no more than a rescued-from-the-company's-junkpile Pentium II laptop bought on E-bay, and will be much more reliable.

-Dave

[R. Exnicios]

What about older laptops that you can get for next to $0 ?

Food for thought

[darius]

Hrm, but that's not the killer app, at least for the needs of a mid-sized university club. In reality, even cheap-*** commodity PC hardware is more expensive than the cheapest boxes (eigertek, favero, SG11, blue sky).

What I'd love to see work done on is eliminating the reel system (and maybe boxes) from the equation.

People have talked about using weaponry as antennae, and triggering signals on the box based on that. Unfortunately, my hardware knowledge is pretty spotty; where would one go about beginning to solve this problem?

This is kinda a general call to see if anybody knows enough about EE to play with this stuff, or maybe point me in the right direction...I could totally do the software work, and I know Will Read, whom I haven't seen around here much lately, would also love to play.

An FIE solution isn't even the preliminary goal; a quick-and-dirty way of getting the correct on-target vs off-target lights, with the right timing, would be a great place to start!

darius

[neevel]

Laptops that old are probably going to be pretty close to worn out, so reliability will be a problem. Regardless of whether the screen gets smashed by a blade or the drive heads decide they've spent too much time next to all this pretty spinning metal without ever knowing what it feels like to touch it, you'll wind up with an unusable scoring apparatus where an Eigertek would still be running. As my division's main armorer & keeper of scoring equipment, I haul enough stuff around to tournaments as is-- I'd rather not have to bring along a few spare Pentium 133-MHz laptops to swap out when you get a BSOD at 14-14 in a semi-final bout.

As Donald said, it's been tried before, and never took off. It'd be a cool thing to make work, but good engineers know that being cool is not the same thing as being the best solution for the application at hand. For a scoring box, you want something that can be hit hard with an epee, dropped on the floor, knocked off of a table, have a bottle of Gatorade spilled on it, be jostled around in a car trunk by Uhlmann upright reels tipping over on top of it, be subjected to freezing & scorching temperatures in same said car trunk, be left in a humid basement over the off-season, and then still be plugged-in and work for 20 years or more, requiring nothing in the way of maintenance beyond perhaps replacing a wall-outlet adapter.

-Dave

[TheArmourer]

Daruis.
There are a couple of problems with eliminating the reels and boxes.
(Talking primarly about foil here - epee is simple and the readily available wrist mounted "boxes" already do most of the job - tho not the timing bit.)
For the sake of avaoiding the wrath of the uber-techies, this is a simplified explanation. I know there are other issues like metalic pistes etc but I'm only considering this as a "a quick-and-dirty way of getting the correct on-target vs off-target lights", as per Darius's question.

There are two primary roles of the circuit.
1. Registering a hit
2. Determining whether or not it is on target.

The first part is easy as a hit is only a case of opening (or closing for epee) a switch. From the point of view of pure circuits, you only need one fencer, one battery and one bulb / buzzer per fencer and you can have two entirely independant circuits. You only need these to interact when it comes to determining the timing between hits.

The second bit - on or off target - is where you need the circuits to be interdependant and it starts to get dificult. The way it's done currently is still analagous to a simple switch circuit:
Open the "foil switch" (ie depress the tip) - registers hit.
Close the "foil to lame switch" - registers on target.

Conventionally, a switch will have two wires connected to it.
In the "foil to lame switch", the foil is connected to one wire and the lame is connected to the other, both via the spools.
If you get rid of a spool, you get rid of one side of the switch, and no switch means no way of determing the on/off target.

To remove the spools and boxes, you effectively need two entirely seperate circuits that can be influenced by each other in a specific way.

One way to do this is to effectivly have a circuit that monitors its own capasitance. When you make the connection between foil point and lame, you can change the capasitance of the circuit, thus recording an on target (provided the hit is regisrered as well).
The easiest example of this effect is with a trasistor radio - find a poor signal, grab the antenna and the reception changes.

It is possible to design a circuit to do this. But, as I'm sure others will confer, the fact that a system isn't comercially available to do it indicates it's quite difficult to do in a simple and reliable way. (And unfotunately my electronics isn't up to in on anything more than a "systems" level.)

BTW - There's no need to use the waepon as an antenna as good small antennae are radily available these days. Just look at your mobile phone.

IMO designing a code based circuit won't help as many clubs as circuit based around logic gates. Components for this are easily available, but not everone has access to eprom progaming kit.

[Epeecurean]

I pretty sure this has been hashed & re-hashed before, but how about just a wireless epee system for a club? I'm thinking of those little plug in epee beeper/buzzers but instead of a beep or buzz it transmits a signal (via bluetooth? radiowave? I have no idea) to a CPU/box which, after a 1/40th-1/50th second delay, shuts off reception of any signal from the other epee's transmitter. This would take care of the single light vs. double light question.

The question of grounding is trickier. Though the whole body is target and we don't have to distinguish between on-target and off-target, we still have to ground out the opponent's guard/weapon and the metallic piste, if there is one. The plug-in could perhaps send a (small) electric current down one of the two wires to the point such that when the point is in contact with the other epee guard it causes that epee's transmitter to send a signal to the CPU blocking the other weapon from sending its signal.

Any electrical/signal engineers here who know whether this is technically possible or are there (as I'm suspecting) some fundamental flaws? I know the FIE and various companies have been working on some solutions, but their requirements are much higher: a three-weapon system that can't be spoofed. I'm thinking of a just a solution for epee in a club environment, where there aren't concerns over electronic cheating.

[TheArmourer]

It's not that simple unfortunately. A signal on one wire has to be with respect to something else connected. It would be like only connecting one pin on an LED and expecting it to light up.

And I wouldn't even bother thinking about trying to get into Bluetooth - complex stuff.

[suregrip]

Hamely, look what you started.

[jeff]

Originally Posted by neevel

the drive heads decide they've spent too much time next to all this pretty spinning metal without ever knowing what it feels like to touch it

Thanks, Dave - that's fhe funniest description of a head crash I've ever read!

[shlepzig]

PC's would probably be fine for a club or a community center that has a few PC's around and want's some extra electric strips.

It would not be good for competitions. PC's are easily reprogrammed and tampered with and could be used to cheat in competitions. The dedicated scoring machines being essentially closed would not be as easy to cheat with without tampering being obvius.

The manufacturers can more easily conform to standards of ruling bodies, and certify that their apparatus works within those standards.

There are ways to secure the software and all that, but then you get out of the range where you are gaining savings or convienence to do so.

As for wireless, and all that, there are ways to do it. They are not that easily and from what I have read the FIE is concerned about jamming or other forms of tampering with the registering of touches in such a system. One using RF especially so. Blue Tooth or IEEE 802.11 are probably good ways for developers to go, but are complicated and require some material investment to develop The market for such things is small, probably too small for the R&D to be really worth it.

An enterprising individual could probably use some ingenuity and Kludge together some existing technology and protocols to make a clever device that does the job. You can use it an enjoy fencing, but it would be difficult to get it to pass regulatory muster from the governing bodies of fencing.

Mind you, I say difficult, not impossible.

Shlep.

[noodle]

Originally Posted by Epeecurean

I pretty sure this has been hashed & re-hashed before, but how about just a wireless epee system for a club? I'm thinking of those little plug in epee beeper/buzzers but instead of a beep or buzz it transmits a signal (via bluetooth? radiowave? I have no idea) to a CPU/box which, after a 1/40th-1/50th second delay, shuts off reception of any signal from the other epee's transmitter. This would take care of the single light vs. double light question.

The question of grounding is trickier. Though the whole body is target and we don't have to distinguish between on-target and off-target, we still have to ground out the opponent's guard/weapon and the metallic piste, if there is one. The plug-in could perhaps send a (small) electric current down one of the two wires to the point such that when the point is in contact with the other epee guard it causes that epee's transmitter to send a signal to the CPU blocking the other weapon from sending its signal.

Any electrical/signal engineers here who know whether this is technically possible or are there (as I'm suspecting) some fundamental flaws? I know the FIE and various companies have been working on some solutions, but their requirements are much higher: a three-weapon system that can't be spoofed. I'm thinking of a just a solution for epee in a club environment, where there aren't concerns over electronic cheating.

this system is possible. i'd be willing to try and play with it if i had the time and resources.

[telkanuru]

Perhapsthis may be of assistance to those who wish to save money. Sabre and perhaps foil following when I get time.

.ckt file is made in Circut Maker. Google for it and DL the student edition (2nd result, I think), if you want. .gif is there otherwise.

[Pepster]

We've mentioned this before (See Thread Epee Beeper Box)

the question was asked there:

Originally Posted by Epeecurean

telkanuru, pepster, cowpaste: have any of you made any progress in creating a wireless epee system which grounds out bellguards and distinguishes between single/double touches?

The answer is : What do they do at the international competitions? I have heard they tried wireless systems there, but never how they work.

There are two basic ways (that I know of) to get around the independent circuit problem. One is the capacitance method - IF my tip is in contact with a piece of metal/lame then the circuit capacitance will be larger. This can be difficult to measure, and is incresingly unreliable with lame's as a fencer sweats. I don't want to try this, because it screams PITA....

The second is the AC signal method. Here comes the science, and I apollogize if this gets heady. Check stuff I've written before on this, as I may have gotten it clearer. In a standard setup, you can detect the closing of the switch by pasing current through it, or measuring a voltage change across it. (i.e.- if your lame is normally GND, and it goes to 6V on a touch, the box knows you got hit) This requires the lame and the opponent's balde have a common ground reference,

To get around this, one can use an AC signal, one that move from, say +6V to -6V 5000 times a second. This is called a 5kHz wave. To receive this signal, you DON'T need a common ground reference. It helps, but it can be gotten around, since the signal is moving. The point isn't for your opponent's circuit to recognize the Voltage level, but the frequency. Which can be done with some simple filters, so long as you use frequencies far enough apart.

SO, to put that together: (Epee) Each fencer has a wireless connection to their blade. Each bell has a 1kHz signal on it, same as the Piste, so when Fencer A hits B's bell, their wireless box sees a signal to tell it "No hit", otherwise, it sends a wireless signal to a box that "I scored a hit, start the lockout timer"

Foil is more complicated: Each Fencer's Lame is 5kHz, the Piste is 1kHz. When a touch is scored, the wireless box looks for no signal (off target) 1kHz (NO hit, piste) or 5kHz (On Target)


Issues with this are many - There can be LOTS of interference problems, or issues with signals crostalking over that nice long 32" antenna. There are also the generic wireless communications issues of interference or Jamming that the bout comitte will require the know-how to moniter for or to stop.

-Pep
- Fogive the typos, I have fat fingers this morning.