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Comment: Re:While I hate the media circus... (Score 0, Troll) 265

by Hillgiant (#48301263) Attached to: Ferguson No-Fly Zone Revealed As Anti-Media Tactic

Slow down sparky. The First Amendment doesn't have the "In order to maintain a well regulated militia"-type clause.

Moreover, even thought the First Amendment clearly forbids Congressional abridgment of the Press, the Supreme Court has allowed multiple exceptions.

So. Take your pocket copy of the Bill of Rights and put it back in your pocket. Grownups are talking.

Comment: Re:Poor material choice (Score 1) 162

by Hillgiant (#47711959) Attached to: Wheel Damage Adding Up Quickly For Mars Rover Curiosity matter how beefy you make an aluminum part, after enough cyclic stresses it will suffer fatigue failure.

You realize that chart has a log scale, right? It is not a matter of designing for infinite life, it is a matter of designing for "infinite enough". This is how they make aluminum engine blocks and heads. Sure it will fail in fatigue eventually. But after 50 years or so, it is time to replace the dern thing anyway. In other words, fatigue strength is just one more variable to design around. Even if the part was made from titanium or steel, they still might make the decision to not design for "infinite" life due to other overriding design considerations. Weight, for example.

The concern with the wheel design was not fatigue itself, but rather a higher peak load during the fatigue cycle. The wheels were not designed for the type of terrain they landed on. More bad luck than bad planning because the type of terrain they landed on had not been observed on Mars before.

In my experience, it is very difficult to successfully design for conditions that have never been observed before.

An inclined plane is a slope up. -- Willard Espy, "An Almanac of Words at Play"