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Links for 2012-09-06

  • Dublin City contact numbers for potholes, dangerous drivers, illegal parking etc.

    I’m sure these are about as useful as a chocolate teapot, but what the hey

    (tags: dublin parking cycling roads safety potholes reporting)

  • Knots on Mars! (and a few thoughts on NASA’s knots)

    amazing post from the International Guild of Knot Tyers Forum:

    While a few of the folks here are no doubt aware, it might surprise most people to learn that knots tied in cords and thin ribbons have probably traveled on every interplanetary mission ever flown. If human civilization ends tomorrow, interplanetary landers, orbiters, and deep space probes will preserve evidence of both the oldest and newest of human technologies for millions of years. Knots are still used in this high-tech arena because cable lacing has long been the preferred cable management technique in aerospace applications. That it remains so to this day is a testament to the effectiveness of properly chosen knots tied by skilled craftspeople. It also no doubt has a bit to do with the conservative nature of aerospace design and engineering practices. Proven technologies are rarely cast aside unless they no longer fulfill requirements or there is something substantially better available. While the knots used for cable lacing in general can be quite varied — in some cases even a bit idiosyncratic — NASA has in-house standards for the knots and methods used on their spacecraft. These are specified in NASA Technical Standard NASA-STD-8739.4 — Crimping, Interconnecting Cables, Harnesses, and Wiring. As far as I’ve been able to identify in the rover images below, all of the lacings shown are one of two of the several patterns specified in the standard. The above illustration shows the so-called “Spot Tie”. It is a clove hitch topped by two half-knots in the form of a reef (square) knot. In addition to its pure binding role, it is also used to affix cable bundles to tie-down point.
    Some amazing scholarship on knot technology in this post — lots to learn! (via Tony Finch, iirc)

    (tags: via:fanf mars nasa science knots tying rope cables cabling geek aerospace standards)