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Sienna
06-26-2008, 08:53 PM
Are you going to establish the maximum velocity and weight that the guns can fire?

(For instance, guns may not fire faster then 400fps with .2g ammo)

sthmck
06-26-2008, 08:57 PM
Safety for people or mech?

Wingzero01w
06-26-2008, 09:51 PM
Probably both. 300fps is the usual airsoft limit.

sthmck
06-26-2008, 10:00 PM
I am wondering if that will be enough to trigger the scoring sensors. What happens if the sensors are to sensitive and triggers when the mech moves wrong. OR if the mech falls over? Or bumps into a building. This is in the wrong thread

Adrenalynn
06-26-2008, 10:15 PM
300fps should be plenty enough force behind the BB. At 400fps I've seen 'em shred clothing.

JonHylands
06-27-2008, 05:14 AM
In the paintball world, we always keep our markers running below 300 fps. Most safety goggles for paintball are only rated at about 350 fps...

In terms of the ammo, I think for the first year anyways we should stick with the standard 6mm plastic BBs. Are there different weights?

Wingzero01w
06-27-2008, 05:23 AM
My paintball gun runs about 250 fps on tournaments on 15 bps. Jon do you also play paintball? And for airsoft plastic pellets don't come in weight classes i think. Im pretty sure it only applies to metal ones.

JonHylands
06-27-2008, 06:27 AM
Yeah, I've got a BT Delta Elite. I run 240 for inside fields, 280 outside.

Wingzero01w
06-27-2008, 07:28 AM
Oh, you play scenario/woodsball? Thats a very nice gun btw. My guns are an invert mini sunset orange, and a smart parts ion with maximum upgrades. I play speedball and Xball and sometimes woodsball.

Sienna
06-27-2008, 03:25 PM
In terms of the ammo, I think for the first year anyways we should stick with the standard 6mm plastic BBs. Are there different weights?

Yes, there are different weights.

0.12g is the lightest common weight, and is shot from the el-cheapo tank rifles and 'entry level' plastic gearboxes usually around 150-250 fps. (example: The tank barrels that we see in the thread)

0.2g is the next lightest common weight, and is shot from the 'mid level' metal gear boxes at 300-400 fps. (example: the metal gearboxes Matt linked too.)

0.25g, 0.3g etc, are also available. (As rounds get heavier, they get slower out of the barrel, but travel more predictably.)

I am basing all this on after hours research the past two days. I don't have an airsoft gun, although I was considering getting one (no better way to test the target sensor!)

Adrenalynn, have you done Airsoft before? If so, is there a way to slow down the metal gearboxes to keep them under 300 fps?

In terms of energy:
200 fps Paintball @ 3.2g = 5.95 J
797 fps BB @ 0.2g = 5.95 J
1030 fps BB @ 0.12g = 5.95 J

JonHylands
06-27-2008, 04:03 PM
I have a pile of airsoft BB's I got a long time ago when I bought a cheap Glock-17 look-alike (back in 1998, I think). I put ten of them on my scale, and it reads 1.8 grams, so 0.18 grams each.

Adrenalynn
06-27-2008, 04:16 PM
The MPG and above generally have adjustments, the LPG (Low Priced) don't

Even though your figures pack the same energy, the 6mm is a lot more focused (smaller area)

DresnerRobotics
06-27-2008, 04:17 PM
Do the higher end ones have a recoil?

Adrenalynn
06-27-2008, 04:43 PM
They have blow-back, which actuates the bolt/upper receiver/slide/...

Sienna
06-30-2008, 07:53 PM
How about we impose a simple 1 Joule muzzle limit? (i.e., you choose the type of ammo, but it can have a maximum kinetic energy of 1J)

Some examples:
423 ft/s @ 0.12g
328 ft/s @ 0.20g
291 ft/s @ 0.25g
265 ft/s @ 0.30g

Adrenalynn
07-01-2008, 12:22 AM
I don't know that I like that 423ft/sec @ .12. I think the entire contest is likely based on 0.12g. As we were crunching the numbers in the other thread, it doesn't look likely that a humanoid is carrying many 0.28g rounds.

It is a nice round number though.

tom_chang79
07-01-2008, 02:27 AM
People might discover that a quadrapod is in the order to carry more ammo... For now, the bipeds are quite disadvantaged in the payload department given same servos used on both types of bots...

DresnerRobotics
07-01-2008, 03:12 AM
People might discover that a quadrapod is in the order to carry more ammo... For now, the bipeds are quite disadvantaged in the payload department given same servos used on both types of bots...

Quadrapods will also have 4 target plates, much easier to hit.

DresnerRobotics
07-01-2008, 03:46 AM
David, that idea was far too good. Moved to the Target/Scoring thread to keep that in the same area of discussion, definitely something we should consider.

Sienna
07-01-2008, 06:08 PM
I think the entire contest is likely based on 0.12g.

I would have to protest most heavily to that. Limiting ammo to .12g would automatically limit what COTS gearboxes I could use to shoot with. To me, that goes over the line. That is why I was trying to stick with a energy based system, to allow the builder to use whatever size (6mm or 8mm) and weight (0.12g, 0.2g, 0.25g, 0.28g, 0.32g, etc....) they wanted.

It doesn't have to be 1J either. If people aren't comfortable with that, scale it back to .9J or something. I was basing the 1J number off of what I read as being a 'safe' number for impact energy.

Adrenalynn
07-01-2008, 08:06 PM
I'm sorry you misunderstood.

Unless you're looking to carry just a few rounds, physics is likely to dictate it. Today's humanoids just aren't strong enough for gun weight, battery weight, ammo weight, barrel weight ... It adds up pretty quick.

Wingzero01w
07-01-2008, 10:48 PM
Unless you spend alot of money to have the top of the line servos out there, those things are pretty powerful, and there getting more powerful.

A-Bot
07-01-2008, 10:51 PM
Unless you spend alot of money to have the top of the line servos out there, those things are pretty powerful, and there getting more powerful.

I agree! Humanoids keep getting better. Why not push the boundaries?

Wingzero01w
07-01-2008, 10:54 PM
Money XD.