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Originally posted by Rotwang:
I don’t think I totally trust Matt to take his finger off the button in the heat of battle.

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I would be thinking of it driving a changeover relay so the vent valve is powered up as soon as the bot is turned on.

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Originally posted by DumHed:

The other nice thing about the manual control is that you can hold the flipper up if you need to.
Holding the button down will fire the ram to full extension (limit switch turns off the gas, but the vent solenoid stays closed until you release the fire button) and it'll sit at the level of the exhaust ports.

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yeah the Ballistic system certainly seemed to work very well.
I think the SodaStream setup could be a nice way to increase performance and give much more "rapid fire" capability (which is probably the best thing about Stealth)
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The Engine Whisperer - fixer of things

Yes the pressure dropped quickly in Ballistic in rapid-fire situations and weight issues resulted in only one 10 or 11-cell 2.4-amp battery pack powering the drive and the compressors.
The hot melt glue was melting after a lot of his fights.

Is anyone going to try to set out the wording for the rules covering the modified rams?

This is how the FRA deals with this type of situation.

8.7.1
Custom made components, or an parts operating above the suppliers max working pressure, must be independently tested and certified at 120% of the maximum system pressure available at that point.
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So even the rain that falls isn't actually going to fill our dams and our river systems

If we are using the Soda stream PRD the ram is going to be operating on only a maximum of 100PSI.
Drilling round holes in the ram to vent the gas IMHO wont make it explode, Quite the opposite it will let the gas out so it has no pressure in it as in ambient pressure.

If it will make you feel better about it I am sure we can pressure test them. 120 PSI coming right up.

I think that would be a good safe gaurd against the inexperienced builder drilling too bigger holes which would weaken the ram to an extend where the ram could fail. You could imagine the impact on our sport if some young fellow shoots a ram end through his chest while playing with his robot in the garage.

Independant certification of modified rams would be a good way to protect the interests of builders, spectators and EOs.
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So even the rain that falls isn't actually going to fill our dams and our river systems

Just so you don’t get the wrong Idea Philip I didn’t mean to give the impression that Robowars or anyone else is going to accept soda stream systems now or at any time in the future, Ajax is trying to get a soda stream machine so he can have a good look at one and he is the one who has Brett’s confidence.

As things stand at the moment I don’t know whether my advice on anything will be welcome but for my own information I am spending time and money researching the situation.

Given my inexperience with Pneumatics, I'm just watching the back and forth of discussion to see when/if a consensus is arrived at.

Personaly, I'm of the opinion that in most cases, it is the builders themselves who should have technical requirements applied to them, rather than the bots, since a technical rulebook assumes that the person who wrote the rules knows more about it than the person building the bot does, which isnt always the case.

No amount of technical rules is going to make a bot built by an idiot safe, and a lot of clever builders will often push the edges of rules in a fairly safe fashion.

However, the rules are there to keep people happy that the playing field is level, and to keep the paper-pushers (insurance companies, venue owners etc) happy that there are some rules.

So, you guys who have strong opinions on how it should be argue out a set of rules, get someone other than me to ok it (since I dont consider myself qualified to do so), and as long as it looks to the paperpushers that its all "by the book", I'm happy too.
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Great minds discuss ideas. Average minds discuss events. Small minds discuss people

thing is who is going to modify their gear then get it tested without testing it themselves first?

so saying it needs to be tested wont really stop the "machine down the bottle to save weight" level of stupidity.
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Mechanical engineers build weapons, civil engineers build targets

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Is anyone going to try to set out the wording for the rules covering the modified rams?

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keep in mind its not just the "surface area" of the holes that gives you the mass flow through the hole.
especially as the holes get smaller
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Mechanical engineers build weapons, civil engineers build targets

If we are talking static pressure test then the ram would need to be held in a suitable jig to limit its travel to a point below the level of the vent holes otherwise the air will leak out.

If the piston is below the level of the vent holes I don’t think the holes are going to have any effect on the pressure the ram can take.

If the question is not the test pressure as Philip has asked but the possibility of the ram tearing in half as it hits the end of its travel then that’s a different type of test altogether.

That involves the weight of the flipper attachment, ratio of the ram to flipper, velocity of the piston and shaft, type of bump stop, diameter of ram and whether it has tie rods or not.

In my earlier post I did suggest that we specify the size and number of holes, It is something that I think will need to be decided if we do get to the stage of working out rules.

The holes probably don’t need to be very big, the vent valve is starting to open at the 75% mark and the firing valve should be closed by the time the ram reaches full travel so the acceleration of the ram and the pressure there in will be dropping of as the volume displaced by the moving piston continues to increase in the last 25% of its travel.

yeah I think engineering some of those sorts of tests would be massively more complex than building the robot in the first place!

Then there's the question of normal, unmodified rams being used in robots. Are they being used safely?
No ram is generally designed to be fired super fast into its end stopper, so some rams will probably fail even at their specified pressure - especially after a lot of hard use.
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The Engine Whisperer - fixer of things

At the moment I don't think there is a requirement for any rule changes.

The current rules cover every thing needed.

The issue at the moment is modified rams. It is clear that if a ram is modified then the manufactures specs are null and void. There for certification is required.

This is only needed if the EO requests it.

Rules

7.2.4. All components must be used within the specs provided by the manufacturer or supplier. If the specifications aren't available or reliable, then it will be up to the EO to decide if the component is being used in a sufficiently safe manner.

and

7.6. All pneumatic components within the robot must be rated or certified for AT LEAST the maximum pressure in that part of the system. You may be required to show rating or certification documentation on ANY component in your system.

Both cover modified pneumatics.

If any thing, a guide for the 'RoboWars Wiki' to help builders would be more beneficial than making the rules harder and more limiting in robot innovation.


Something to remember is that most pneumatics that are available, have been certified at 145 - 150 psi by the manufacture.


Sorry for the slow respones I am working long hours at the moment. I will write some more on the weekend.
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It's all about the destruction.