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Powerhead

Thread Status: Hello , There was no answer in this thread for more than 60 days.
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I

Iyadiver

Mr. Long Post
Apr 22, 2002
998
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SK,

Just trying to tweak the design a bit.

A CO2 cartridge u will be using can't be the 10 x 3 cm size. Must be the one size up ..correct ?

As far as I can recall , the time required to discharge the entire CO2 content will be at least 3-4 seconds, depending on where you hit cause total fish meat will restrict air flow and how big is the internal air hole diameter of the needle.

What I am still figuring out is how do you keep the needle that poke the CO2 canister to remain in place (inside the CO2 canister ) while liquid CO2 is being transformed to gas state.
There must be so form of lock you must use to keep needle in CO2 canister or the entire housing must be air-tight, thus air can only escape to the hole in the needle.

At 1,800 psi of pressure, even with an air-hole in the needle to release CO2, the CO2 will have enough pressure to push away the needle assy cause of this massive pressure.

I guess u must make that needle lock and gas tight chamber for maximum delivery both in volume and pressure.

That barb is a must, great idea cause the jet effect of the CO2 will push away the needle from the fish flesh. Even when u are using a stick, I doubt the shark will remain in position as long as 4 seconds.........I bet it will run off.

Just my thoughts...he he he

IYA
 
Murat

Murat

Promethian
Jun 21, 2002
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Originally posted by Shadowkiller
IThe trick is to keep the needle in the shark while the cartridge is emptying. And we cant expect co-operation from the shark..




Yea cetainly you can`t expect co-operation from shark:D :D :D

So your system must deliver all the CO2 in the tube in milliseconds.:hmm
 
Shadowkiller

Shadowkiller

Digital Hunter
Jul 30, 2002
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Iyadiver: I was thinking of using the beer keg type cartridges. And yes the needle will get pushed out but the subsequent increase in pressure will drive the assembly into a self sealing situation. A rubber seal between the case and "B" (inside the case naturally) will ensure an airtight casing with the only exit being through the needle. Plumbers tape will keep the threaded cap sealed.

Murat: with a barb to keep the needle in place we can afford to let all the CO2 discharge more slowly... I dont think we need to deliver all the CO2, its not as if there is a prescribed dosage for sharks. Just enough to make the shark want to be somewhere else.

Ultimately someone is going to have to build a prototype and fix any unforseen problems as they occur. Hopefully without serious harm to the pioneer..
 
Murat

Murat

Promethian
Jun 21, 2002
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Barb??? If you use barb how will you protect the powerhead from the shark that take it with itself????
 
Griff

Griff

Certified SCUBA Rider
May 7, 2002
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Guys, you've all been saying how dangerous using live rounds for a powerhead is, but i'd be more worried about a CO2 into hyperdermic needle. what i am thinking, and please correct me if i'm wrong, when accidents happen, and they do happen, a bullet needs to find some vital organ etc, but a CO2 needle just needs to find an artery or vein and you have more bends than a bowl of spagettie.
maybe you'd be better off paying an arm or a leg to the shark, than having fizz-pop for blood.
what do the docters say?

what about going for more of a bang than a bite?
has anyone tried something like a stun grenade.
 
Abriapnea

Abriapnea

New Member
Jan 16, 2002
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Sheesh , Griff ; that might be getting a bit extreme . Imagine the effect a stun grenade would have on YOU :duh
I think I'll rather take my chances with the shark , has worked for me till now .
 
Shadowkiller

Shadowkiller

Digital Hunter
Jul 30, 2002
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Griff,

I have to agree with Abri, a stun grenade is a little indiscriminate. Not to mention that few of us have access to military surplus. :D

Your point on safety is well taken. However I firmly believe that the gas powerhead is a safer alternative to a bullet powerhead. My experience with shotgun shell kangaroo traps and pop sticks have taught me a few lessons and left me slightly deaf in one ear.

The gas PH will not be triggered simply by being dropped. A simple plastic clip will prevent the needle from being driven home accidentally during transport. When it is made ready for use then the user must, of course, take great care not to fire it into him/her self or slam it home by hand. A simple rubber cover will prevent accidental punctures while it is stored on a dive belt (or up a sleeve).

A bullet powerhead can go off simply by being dropped or roughly handled. And it can do some serious damage even a few feet from the user. Such injuries often comprise of severed limbs or eye/facial damage.

Please believe me when I say that I would not have posted this design if I did not believe that it was a safer alternative to the existing bullet powerheads. Being an engineer by profession I am all too aware of my responsibilties and obligations where safety and the well being of others are concerned.

Of course no design is flawless and anything designed to kill is dangerous, not only to its intended target but also to the user. Consider firearms and our spears themselves. Accidents can and do happen (Greek incident) but as long as we have discussions like this we can work together to minimise the risks and make each other aware of the dangers. Ultimately the individual has to make the choice of whether to build and use this design or not. I can give no gurantees or assurances concerning the safety of the user as a lot depends on the quality of the materials used, the workmanship and the care taken by the user.

Your life, your choice.

:)

Chose life, chose to dive!
 
DeepThought

DeepThought

Freediving Sloth
Sep 8, 2002
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Grenades, Ammos etc...

:)

Ok, so here is the new design:

a power head with a Co2 cartridge, and a grenade louncher mounted below the spear gun.

Someone should also check, maybe liquid Co2 conduits electricity better than water and thus with the little addition of a stun gun alow us to build a nice and jolty thunderstorm inside the shark's body before blowing it to hell.

Ofcourse don't forget to collect the remains and take them to the land for proper cyanide immersion before burinng them.

Though I personally will never feel safe before harnessing the power of cold fusion for those purposes. :duh

Can't we just invent a pressure squirt-gun with some sea cucumber (Oceanus Skunkus) scum cartridges?

Michael.
 
Griff

Griff

Certified SCUBA Rider
May 7, 2002
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Ja, ja, ja. i know that a stun grenade is a tad overkill. i was thinking more on the lines of a cherry bomb that will work underwater. iya, how?
with the CO2 injection, my point is that if you do get jabbed, then the result is probably fatal, and there is no way to 100% guarantee not getting jabbed, especially considering the conditions on a boat. so i think that putting a cap on ect is making it a lot safer. i guess it comes down to risk. what are the chances of dying to sharkbite, bullet or CO2. take the smallest risk and use that. i personally think that if there is a big shark that wants you for dinner, you wont even see it before it hits you.
I was watching that program on the whites in false bay. they use the murk to stalk the seals, and charge straight up at them, like an ambush. scary stuff, but at least its over quickly. for the smaller stuff, then i like anderson's bayonette idea.

mark
 
Shadowkiller

Shadowkiller

Digital Hunter
Jul 30, 2002
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You are absolutely right Griff. Most people who get bitten dont see the shark before it hits them. Its more about swimming in areas with know shark populations that are naturally aggressive and may need "putting down".

Does anyone know what freqency the Anti-Shark pods emit? It should be pretty simple to rig up an electronic circuit which emits the same freq.

I am after all an ELECTRICAL engineer...

:king
 
Griff

Griff

Certified SCUBA Rider
May 7, 2002
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Originally posted by Shadowkiller
I am after all an ELECTRICAL engineer...

:king

electrical, isnt that one of those sub categories of civil :king :king :king engineering? :t

i've got a question regarding electronics. is there a circut that emmits a random signal that could be used on a switch?

mark
 
Shadowkiller

Shadowkiller

Digital Hunter
Jul 30, 2002
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Originally posted by Griff


electrical, isnt that one of those sub categories of civil :king :king :king engineering? :t


mark
Funny Griff. Reeaaaallll funny.:ban

:D

Im not to sure what exactly you mean. Do you mean a randomly activated switch or a switch that activates a random sound?

Either is pretty simple if youre using a PIC or similar microprocessor.

Heres to us Engineers! (I assume youre one)
:friday
 
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Griff

Griff

Certified SCUBA Rider
May 7, 2002
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yep, the only problem with being an engineer is the amount of explaining that you have to do.

thanks for the info on the PIC
 
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Murat

Murat

Promethian
Jun 21, 2002
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There are gates for this kinds of job.Basics are AND OR NOR NAND FLOOPERS and so so so......If you have enough knowledge you can make unbelivable microproccesors with them.But its too challanging even to very good engineers to make complex chips but not impossible.It`s even depends on your bugget how much can you pay for the research??? And can you offer 10k dollars after making the design to produce it?


So it not that easy man to specific microchip.This why the electrical and electronic enginners gets the one of the highest incomes monthly:D :D :D ;) ;)
 
Shadowkiller

Shadowkiller

Digital Hunter
Jul 30, 2002
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uhhmmm Murat. Where do you get your info from? :hmm

No-one builds Microprocessors from scratch anymore..
They all contain the basic components, ie ROM, cache, R/W module etc. So pre-existing design are modified to suit new streamlining processes.

A PIC or AVR chipc is programmable. That means its has a PC interface and you write a program in C or Assembler language, write the program to the EPROM and the chip will perform the programmed functions.

A very basic laboratory excersise at Uni is to do frequency analysis and processing on a I86 chip. It similar to an AVR but simpler to use. Costs a lot more too.

Modern IC chips are designed by a computer program after the engineer enters the required circuit descriptions. No research required, just production costs. But that isnt what Griff is after, why re-invent the wheel? (Modern research in microprocessor areas is focused on breaking the micron barrier.)

For Griff's purpose I would recommend he go to an Electronics store where they can advise him on Microprocessor learning packages which he can take home and program to his hearts content. All he has to do is learn C. :D

Griff: PM me with more details on what you want to do and I can get more specific.
 
Murat

Murat

Promethian
Jun 21, 2002
2,982
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Originally posted by Shadowkiller
uhhmmm Murat. Where do you get your info from? :hmm

No-one builds Microprocessors from scratch anymore..
They all contain the basic components, ie ROM, cache, R/W module etc. So pre-existing design are modified to suit new streamlining processes.

A PIC or AVR chipc is programmable. That means its has a PC interface and you write a program in C or Assembler language, write the program to the EPROM and the chip will perform the programmed functions.

A very basic laboratory excersise at Uni is to do frequency analysis and processing on a I86 chip. It similar to an AVR but simpler to use. Costs a lot more too.

Modern IC chips are designed by a computer program after the engineer enters the required circuit descriptions. No research required, just production costs. But that isnt what Griff is after, why re-invent the wheel? (Modern research in microprocessor areas is focused on breaking the micron barrier.)


Well i get these infos. from prev. courses.I passed digital logic design last year.Did you mean comp. does all the design for u? U just enter what you want? What is this software`s name? I although know little c++ i will take algorithms and datacharts this semester.Computer does the design so your job is writing the right software for this chip by using C ????Its sounds like end for Electrical And Electronical Engineers long live Comp. Engineers:king .

Griff;

If you need help be more clear plz.I will glad to help you if i can.
 
Shadowkiller

Shadowkiller

Digital Hunter
Jul 30, 2002
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Originally posted by Murat

Its sounds like end for Electrical And Electronical Engineers king .

You are not too far off the mark there. Most advanced designs are done by a computer program. Intel and Athlon use Supercomputers to work out chip configurations. I dont know the name of the software they use but I can gurantee its not for sale!

My elective subjects (I'm in my seventh and last year of study) that dealt with chip design focus on the basic outlays of an Integrated Chip and how to program Microprocessors.

You can get software to do most things these days. From circuit board layouts to self-writing genetic algorithms.

Thanks the big blue Dolphin we still have to spearfish by hand!
 
Murat

Murat

Promethian
Jun 21, 2002
2,982
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Originally posted by Shadowkiller


You are not too far off the mark there. Most advanced designs are done by a computer program. Intel and Athlon use Supercomputers to work out chip configurations. I dont know the name of the software they use but I can gurantee its not for sale!


As i know the super comp. is not for sale toorofl
Supercomputers! ! ! I wish to had one.Beyond the quantum physic.Liquid Hydrogen for cooling procces.May be the MUONIUM is not very far! ! !
 
andrsn

andrsn

Just visiting...
Aug 26, 2001
1,213
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keepin it simple..

first off, here's to all the double E's out there. :friday

why use a ferrari to dig a ditch? no need for a ucontroller or uprocessor at all. use a 555 timer w/ a variable resister(pot) for frequency changing. just need a driver to power your output. much simpler than using a controller chip. :D no programming. and costs about $3usd. :eek:

i'm in the works of designing a fish attractor w/ this setup. highly illegal for spearfishermen but it's soley for research, i assure you. ;) :D :cool:

later,
anderson

is the glass half empty or half full? pessimist: half empty; optimist: half full; engineer: twice as big as it needs to be! :D
 
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