This Year’s Nobel Prizes Are Straight Out Of Science Fiction

In the 1966 science fiction movie Fantastic Voyage, medical personnel are shrunken to the size of microbes to enter a scientist’s body to perform brain surgery. Due to the work of this year’s winners of the Nobel Prize in Physics, laser tools now do work at this scale.

Arthur Ashkin won for his development of optical tweezers that use a laser to grip and manipulate objects as small a molecule. And Gérard Mourou and Donna Strickland won for coming up with a way to produce ultra-short laser pulses at a high-intensity, used now for performing millions of corrective laser eye surgeries every year.

Here is a look at these inventions, their inventors, and the applications which made them important enough to win a Nobel.

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Hack My House: Running Raspberry Pi Without An SD Card

Many of us have experienced the pain that is a Raspberry Pi with a corrupted SD card. I suspect the erase-on-write nature of flash memory is responsible for much of the problem. Regardless of the cause, one solution is to use PXE booting with the Raspberry Pi 3. That’s a fancy way to say we’ll be booting the Raspberry Pi over the network, instead of from an SD card.

What does this have to do with Hacking My House? As I discussed last time, I’m using Raspberry Pi as Infrastructure by building them into the walls of every room in my house. You don’t want to drag out a ladder and screwdriver to swap out a misbehaving SD card, so booting over the network is a really good solution. I know I promised we’d discuss cabling and cameras. Think of this as a parenthetical article — we’ll talk about Ethernet and ZoneMinder next time.

So let’s dive in and see what the Preboot Execution Environment (PXE) is all about and how to use PXE with Raspberry Pi.

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Will Drones And Planes Be Treated As Equals By FAA?

Soon, perhaps even by the time you read this, the rules for flying remote-controlled aircraft in the United States will be very different. The Federal Aviation Authority (FAA) is pushing hard to repeal Section 336, which states that small remote-controlled aircraft as used for hobby and educational purposes aren’t under FAA jurisdiction. Despite assurances that the FAA will work towards implementing waivers for hobbyists, critics worry that in the worst case the repeal of Section 336 might mean that remote control pilots and their craft may be held to the same standards as their human-carrying counterparts.

Section 336 has already been used to shoot down the FAA’s ill-conceived attempt to get RC pilots to register themselves and their craft, so it’s little surprise they’re eager to get rid of it. But they aren’t alone. The Commercial Drone Alliance, a non-profit association dedicated to supporting enterprise use of Unmanned Aerial Systems (UAS), expressed their support for repealing Section 336 in a June press release:

Basic ‘rules of the road’ are needed to manage all this new air traffic. That is why the Commercial Drone Alliance is today calling on Congress to repeal Section 336 of the FAA Modernization and Reform Act of 2012, and include new language in the 2018 FAA Reauthorization Act to enable the FAA to regulate UAS and the National Airspace in a common sense way.

With both the industry and the FAA both pushing lawmakers to revamp the rules governing small remote-controlled aircraft, things aren’t looking good for the hobbyists who operate them. It seems likely those among us with a penchant for airborne hacking will be forced to fall in line. But what happens then?

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How Precise Is That Part? Know Your GD&T

How does a design go from the computer screen to something you hold in your hand? Not being able to fully answer this question is a huge risk in manufacturing because . One of the important tools engineers use to ensure success is Geometric Dimensioning and Tolerancing (GD&T).

A good technical drawing is essential for communicating your mechanical part designs to a manufacturer. Drafting, as a professional discipline, is all about creating technical drawings that are as unambiguous as possible, and that means defining features explicitly. The most basic implementation of that concept is dimensioning, where you state the distance or angle between features. A proper technical drawing will also include tolerances for those dimensions, and I recently explained how to avoid the pitfall of stacking those tolerances.

Dimensions and tolerances alone, however, don’t tell the complete story. On their own, they don’t specify how closely the geometric form of the manufactured part needs to adhere to your perfect, nominal representation. That’s what we’re going to dig into today with GD&T.

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Bitcoin’s Double Spending Flaw Was Hush-Hush During Rollout

For a little while it was possible to spend Bitcoin twice. Think of it like a coin on a string, you put it into the vending machine to get a delicious snack, but if you pull the string quickly enough you could spend it again on some soda too. Except this coin is worth something like eighty-grand.

On September 20, the full details of the latest fix for the Bitcoin Core were published. This information came two days after the fix was actually released. Two vulnerabilities were involved; a Denial of Service vulnerability and a critical inflation vulnerability, both covered in CVE-2018-17144. These were originally reported to several developers working on Bitcoin Core, as well as projects supporting other cryptocurrencies, including ABC and Unlimited.

Let’s take a look at how this worked, and how the network was patched (while being kept quiet) to close up this vulnerability.

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Remember When Blockbuster Video Tried Burning Game Cartridges On Demand?

By the onset of the 1990s one thing was clear, the future was digital. Analog format sales for music were down, CD sales were up; and it was evident, at least in the US, that people were bringing more computing devices into their homes. At the beginning of the decade, roughly 1 in 3 American households had a Nintendo Entertainment System in them, according to this Good Morning America segment.

With all those consoles out there, every shopping season became a contest of “who could wait in line the longest” to pickup the newest titles. This left last minute shoppers resorting to taking a rain check or return home empty handed. Things didn’t have to be this way. The digital world had emerged and physical media just needed to catch up. It would take an unlikely alliance of two disparate companies for others to open their minds.

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Laser Noob: Getting Started With The K40 Laser

Why spend thousands on a laser cutter/engraver when you can spend as little as $350 shipped to your door? Sure it’s not as nice as those fancy domestic machines, but the plucky K40 is the little laser that can. Just head on down to Al’s Laser Emporium and pick one up.  Yes, it sounds like a used car dealership ad, but how far is it from the truth? Read on to find out!

Laser cutting and engraving machines have been around for decades. Much like 3D printers, they were originally impossibly expensive for someone working at home. The closest you could get to a hobbyist laser was Epilog laser, which would still cost somewhere between $10,000 and $20,000 for a small laser system. A few companies made a go with the Epilog and did quite well – notably Adafruit used to offer laptop laser engraving services.

Over the last decade or so things have changed. China got involved, and suddenly there were cheap lasers on the market. Currently, there are several low-cost laser models available in various power levels. The most popular is the smallest – a 40-watt model, dubbed the K40. There are numerous manufacturers and there have been many versions over the years. They all look about the same though: A blue sheet metal box with the laser tube mounted along the back. The cutting compartment is on the left and the electronics are on the right. Earlier versions came with Moshidraw software and a parallel interface.

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