Category: Technology & ideas

scientific developments, inventions, design, sci fi

Systems and safety

What I’ve failed to report for a couple of months is that the boat finally became a catamaran, same overall dimensions, same walls, same slightly narrower deck, it required little reworking.

Main reason was overall safety.  Even though cats suffer one overwhelming negative – that if flipped, they stay flipped – giving them sufficient beam [usually half the length, therefore 21 feet] and reducing sail area, has usually been sufficient around the world.… More here ...

Ventilation

For Ivan – difficult to make it shortwinded:

All sailboats can be upended and there must be design/build strategies in place if that continues past 6 seconds [rule of thumb] in 180 degree knockdowns.  That’s the usual keelboat allowance but a multihull stays over.  Most commercial charter cats are designed never to go over – if they do, they’ll flood and sink.

Most larger monos have dorades and commercial versions of these devices sometimes use a ballfloat mechanism to block the gap when the boat is inverted and water pressing.  I don’t like them.… More here ...

Reflections on stability

Dearieme wrote, about these machines:

We used a hovercraft once. Dear God it was noisy.

Good to see he found God but apart from that, if dem hovercraft are noisy but soft in ride, and hydrofoils, I can attest, are noisy and hard in ride, then it seems to make sense that either an in-the-water boat or a WIG would be the way to go.

What finally put me off hydrofoils was this:

That was a puzzle as cats of this size are usually far more stable. On a second look, they were using four foils but the tech says that when foils reach a certain angle, they react and stabilize, so what went wrong?… More here ...

“Self-driving car” and “disaster” is no oxymoron

We probably need go no further than the opening paragraphs to get to the nub of the matter:

IT’S BEEN NEARLY a year and a half since Joshua Brown became the first person to die in a car driving itself.

In May 2016, Brown was on a Florida highway in his Tesla Model S using Autopilot, the semi-autonomous driver assist feature that handles steering and speed during highway driving.

Tesla has always warned drivers that Autopilot isn’t perfect. According to car’s driving manual and the disclaimer drivers accept before they can engage it, the system should only have been used on highways with clear lane markings, strict medians, and exit and entrance ramps.

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Tracking the future

The future:

The USA is embarking upon a further upgrade of the M1 Abrams series, the M1A2 SEP v.3, with the SEP v.4 to follow in the 2020’s.  Russia has unveiled the T-14 Armata, a main battle tank that will be accompanied by a series of other armored vehicles built on the same platform.

Israel has been working on a successor to its Merkava series tanks for some time.

Here’s a video simulation, showing what it calls the Carmel tank project.  It’s still a concept, and doesn’t even exist in prototype form yet, but shows how that country is thinking about the future of main battle tanks and armored fighting vehicles.  It’s rather different to US and Russian thinking on the subject.

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Voyager moons

The Voyager probes launched to study the planets, but they discovered the wonder of the solar system’s moons:

Voyager 2 actually launched first, on August 20, 1977. Voyager 1, the faster craft, left Earth 40 years ago today—September 5, 1977. With thousands of photographs, Voyagers 1 and 2 revealed the outer solar system in all its splendor for the very first time. But for as much as they told us about the gas giants planets, the legendary probes may have made their most shocking revelations by showing us that our own moon is one of the least interesting natural satellites around.

The Voyager flybys of alien moons led to profound discoveries, including active geology in the frigid outer reaches of the solar system, volcanoes that spew lava hundreds of miles high, and early indications of surface lakes and rivers of flowing hydrocarbons.

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