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Comment Re: Robotics withotu a real robot is pointless (Score 1) 78

Ummmm.... anything involving a motor? A 6-axis accelerometer + gyro? Any off the shelf infrared distance sensor module (like Sharp's)?

Most really interesting robotics projects ultimately require some degree of computer vision. As luck would have it, CV is one of the few things directly relevant to robotics that can BE effectively learned using only a PC (with cheap webcam).

Comment Re: Isn't this what --preserve-root is for? (Score 1) 699

If the headphone jack state can be read by UEFI, one sensible option would be to require that an Android or iPhone-type 4-lead stereo headset be plugged in and the headset's "action" button (which shorts two lines together) pressed to trigger or enable actions that could be destructive (or allow recovery from them).

Example: rm -rf / borks UEFI. Plug in the headset & power up while pressing the action button to get to a menu that allows you to restore UEFI from an immutable ROM image that can then be updated to a newer one, flash a newer UEFI image, or wipe the nvram and restore it to default values from the current bootloader.

Or they could license FTDI's IP and embed a JTAG programmer in the USB controller, so you could them do a hardware reflash from another computer (or even an Android phone with USB-OTG cable).

For security (and prevent drive-by attacks by rogue USB peripherals), they could add a jumper & disable JTAG-via-USB unless explicitly jumpered. To keep people from LEAVING it jumpered, the system could refuse to continue past the bootloader until the jumper gets removed.

Comment Robotics withotu a real robot is pointless (Score 2) 78

You could, but it would be largely pointless. In the real world, unless you're an entity like NASA (with resources to match), hardware almost never behaves exactly the way it's officially supposed to. Electronics can be simulated perfectly. Mechanical devices? Not so much. Your simulated stepper motor makes certain assumptions about torque, inertia, etc. that are mostly guaranteed to be invalid once you try it in a real device with worn bearings operating running across a shag carpet or wet floor.

The sad fact is, robotics isn't a hobby for poor people. The electronics part is cheap thanks to Arduino and RasPi (and Edison, and ...), but once it's time to start adding hardware, all bets are off. Sure, you can make a sub-$100 robot that can follow lines and avoid running into walls, but the moment you get bored and want to add real sensors & stuff, prepare to fork out some SERIOUS cash.

Just to give one example:'s AX12-AHW robotic arm kit. It's $399... not counting the 7 Robotis AX-12A digital servos you'll have to buy for around $45 apiece, and the power supply, and the controller, unless you already have them. Now, this is an awesome, kick-ass robotic arm. It's well-designed, and can probably be used to do useful things. But damn, it's expensive.

All kidding aside, the iRobot Create is one of the best platforms to get started with... it's under $100 at Amazon, and gives you not only the ability to detect walls and collisions, but also gives you the ability to avoid running down stairs & furnishes data about its actual, measured motion.

If you really want to do something meaningful without a real robot, get a cheap webcam for your PC and learn how to use OpenCV. If you ever get to work on a real robot someday, OpenCV programming knowledge will be very useful... especially since RasPi-based robot controllers can use the same cheap webcams as desktop PCs (assuming they support Linux & have open-source drivers you can build for the Pi).

Big tip to programmers who want to get into robotics: if you anticipate needing hardware that can't be purchased off-the-shelf, become friends with a mechanical engineer. They understand things like drivetrains the same way you understand things like recursion & objects... and he (or she) probably finds programming to be about as frustrating and alien as you find trying to bolt things together (dropping screws & nuts into the carpet, gouging your finger with the screwdriver, etc). There's a tiny bit of overlap between the electronic and mechanical realms, but most people who develop robots are teams of two (or more) with complementary skill sets.

Comment Re:Fallacy (Score 1) 329

The big difference is that if an American, European, or Japanese company makes a good-faith effort to source quality components and produce high-quality stuff, there's a very good chance it will ultimately be of high quality.

In China, it's almost impossible to guarantee quality because supply-chain integrity can't be objectively guaranteed.

In the US, Boeing can read the laser-etched serial number from a screw or bolt and literally audit it backwards to every step from mine to factory to delivery. In China, you'd be laughed at if you even tried to do that, because auditing only works when the auditors themselves are trustworthy. When you have to start recursively checking and cross-checking literally everyone down to the office cleaning lady and employees at the truck stop where the truck driver ate dinner, the task becomes completely hopeless.

Comment Re: Android security? lol! (Score 1) 126

That was briefly true for a short time in the 90s (the ESS switching protocol exposed functionality whose security assumed it was under the control of a responsible phone company, but could be abused by malicious clients), but not any more. The vulnerability was fixed, and the FCC made it clear that any charges for fraudulently redirected calls HAD to be refunded to consumers. That's part of the reason why mobile phone carriers block calls to those numbers outright... they aren't required by law to participate, and they don't want to be bothered by the customer service nightmare (and financial losses) every time some incident occurs.

Comment Re:Not needed (Score 1) 481

Unless it has a hard food disposer. Then, you can load up dishes that have literal chunks of food on them.

IMHO, two non-negotiable features any dishwasher I buy has to have:

* hard food disposer

* heated dry. I don't give a fuck if unheated drying modes get the non-plastic dishes mostly dry. I want my goddamn dishes sterilized, baked, and bone-dry when they come out.

#2 was the entire reason why I didn't buy a Samsung DW80J3020US last month. It's a damn shame, too... Samsung has nice dishwashers that just happen to be gimped by the omission of heated drying.

Comment Re:So we never own anything buy? (Score 1) 197

Except nimble competitors who outsource everything will NEVER be able to compete long-term against massive vertically-integrated companies like IKEA, if only because their vertically-integrated competitors will always be able to under-bid them to get the Walmart purchase, and will be the only ones with the means to shave that last fraction of a cent that means the difference between eventual bankruptcy and ongoing profitability.

Nimble companies that outsource everything are good at driving innovation and bringing revolutionary new products to market, but in the long run the best they can hope for is to get purchased before they get bankrupted by a slower-moving vertically-integrated competitor who'll sell products that are kind of good for a fraction of the price and ultimately wring 100% of the economies of scale from the process.

Case in point: General Motors. Say what you like about its cars and bloat. They don't just build cars... they literally own their own bank, and can effectively print money by making loans. If you can't get approved by a bank for an auto loan, and only GM will finance your purchase, the value and quality of GM's competitors is meaningless. That gives them a staggering market advantage over companies like Tesla. Back when Tesla started selling cars, you'd have been laughed at if you walked into your bank and asked them to approve a loan for 100% of the purchase price, but the same bank would have rubber-stamped the approval for a zero-down loan to buy a regular car at twice the price.

Comment Re:You can't lock up hardware (Score 1) 201

For the most part, all x86-IA32/AMD64-based PC architecture hardware (except for anything involving 3D graphics, HDCP, the decryption and playback of protected media content, hard drive controllers, and pretty much anything involving the firmware of a radio chip intended for use by anyone who isn't a licensed ham radio operator) is Open Hardware.

There. Fixed it for you.

Comment Re:Billions of people vs. thousands (Score 1) 289

Not really. Most of South Florida was ORIGINALLY low-lying, but AFAIK, it hasn't been legal to build a new structure whose main living floor isn't at least several feet above sea level since at least 1926. Our roads don't flood because of rising sea levels, they flood because our county government is criminally incompetent and doesn't maintain storm drains properly.

Comment Re:To higher ground? (Score 1) 289

> The ground is water permeable.

So dig Florida-style finger canals to create new, valuable waterfront property to sell to foreigners for vacation homes, and use the revenue to pay for raising the rest of the main island for Kiribati's own residents.

Permeable ground just means you can't rely on levees or dikes to keep land that's below sea level dry. Raise the terrain itself (via dredged fill dirt) above sea level, and the problem is solved. The city of Chicago literally raised most of its land & buildings (and reversed the direction of the Chicago river) more than a hundred years ago. See:

Guaranteed: if Kiribati were formally abandoned by its inhabitants and evacuated in some grand public gesture of eco-catastrophe, someone else (China, Russia, militant libertarians, etc) would show up, occupy the islands one by one, and declare ownership & sovereignty within a matter of days.

Comment Re:To higher ground? (Score 1) 289

> The Russian won't be able to heat his home when the economy collapses due to climate change

Er.... out of all the countries on Earth, with the possible exception of Canada, I struggle to think of a country that's more likely to be a net beneficiary of climate change than Russia.

Obligatory joke: In Soviet Russia, climate changes YOU...

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