definitive statement regarding PCA rules and ISAAC?
01-07-2008, 06:23 PM
#46
Three Wheelin'
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1) You cannot push on a rope:
2) Dampers control velocity which are key to kinetic energy (KE=0.5mv^2):
There is no way a tether can manage energy as effectively as a damper.
01-07-2008, 09:16 PM
#52
Lifetime Rennlist Member
There are two characteristics of dampers that are drastically different than ropes in a dynamic environment. Compare the Isaac and the Isaac Link. The Link has ropes, the original Isaac has dampers.
1) You cannot push on a rope:
2) Dampers control velocity which are key to kinetic energy (KE=0.5mv^2):
There is no way a tether can manage energy as effectively as a damper.
1) You cannot push on a rope:
2) Dampers control velocity which are key to kinetic energy (KE=0.5mv^2):
There is no way a tether can manage energy as effectively as a damper.
You did not say how these relate to injury. Where is the evidence that a lower number is better than a number almost as low? If they both mitigate injury, then what is the REAL WORLD difference?
And, if the issue is rope vs. damper, how come the HANS numbers (whatever they mean) seem so much better than the Isaac Link. If the HANS is so bad, why would you sell a product that is even worse?
I am sure I am coming off as an a$$hole, but you keep evading the questions about real world data and injuries so I will keep coming across that way.
01-07-2008, 09:42 PM
#53
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Well...
Alive is indeed alive, Mark, but a lower number will always be theoretically better. How can anyone quantify things any better than that? It stands to reason that given the variability, the lower number may help someone, somewhere, someday, under some cirtcumstance. The driver with the cerebral annurism that doesn't pop because of a lwo number.
Real hard-fact results where none exist. How can anyone have enough data to prove this point either way? There are likely not enough instances to prove anything definitively, with any statistical certainty.
Alas, in the world of the engineer, in this case, lower is better. It stands to reason. How high it stands is a question awaiting proof.
One thing for sure; for $300, you can't beat the Link!
Alive is indeed alive, Mark, but a lower number will always be theoretically better. How can anyone quantify things any better than that? It stands to reason that given the variability, the lower number may help someone, somewhere, someday, under some cirtcumstance. The driver with the cerebral annurism that doesn't pop because of a lwo number.
Real hard-fact results where none exist. How can anyone have enough data to prove this point either way? There are likely not enough instances to prove anything definitively, with any statistical certainty.
Alas, in the world of the engineer, in this case, lower is better. It stands to reason. How high it stands is a question awaiting proof.
One thing for sure; for $300, you can't beat the Link!
01-07-2008, 10:46 PM
#54
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Normally I get enough tech and engineering argument at work, however this time I can't resist to argue this statement. It just bothers me when people say never in regards to engineering. How do you know the dampener isn't the reason it wasn't allowed by SFI?
What is the ISAAC's dampening media - hydraulic, pneumatic? How can you accurately control the loss of that media over a period of time (seals leak!)? One could argue that the tether used on the HANS is easier to maintain over a period of time (especially by untrained personnel - like most club racers when compared to professional racers) than the dampening system of the ISAAC. It is easier to control the construction of a fiber in a factory than the maintenance of a dampener over time.
I'm no professional racer or mechanic, just a lowly working engineer that calls 'um like I see 'um. If I missed something major, please somebody let me know - I'll admit it when I'm wrong.
What is the ISAAC's dampening media - hydraulic, pneumatic? How can you accurately control the loss of that media over a period of time (seals leak!)? One could argue that the tether used on the HANS is easier to maintain over a period of time (especially by untrained personnel - like most club racers when compared to professional racers) than the dampening system of the ISAAC. It is easier to control the construction of a fiber in a factory than the maintenance of a dampener over time.
I'm no professional racer or mechanic, just a lowly working engineer that calls 'um like I see 'um. If I missed something major, please somebody let me know - I'll admit it when I'm wrong.
