How Art Became Science In Machining

Machining is one of those fascinating fields that bridges the pre-scientific and scientific eras. As such, it has gone from a discipline full of home-spun acquired wisdom and crusty old superstitions to one of rigorously analyzed physics and crusty old superstitions.

The earliest machinists figured out most of what you need to know just by jamming a tool bit into spinning stock and seeing what happens. Change a few things, and see what happens next. There is a kind of informal experimentation taking place here. People are gradually controlling for variables and getting better at the craft as they learn what seems to affect what. However, the difference between fumbling around and actually knowing something is controlling for one’s own biases in a reproducible and falsifiable way. It’s the only way to know for sure what is true, and we call this “science”. It also means being willing to let go of ideas you had because the double-blinded evidence clearly says they are wrong.

That last part is where human nature lets us down the most. We really want to believe things that confirm our preconceived notions about the world, justify our emotions, or make us feel better. The funny thing about science, though, is that it doesn’t care whether you believe in it or not. So go get your kids vaccinated, and up your machining game with scientific precision. Let’s take a look.

Continue reading “How Art Became Science In Machining” →

X-Rays Are The Next Frontier In Space Communications

Hundreds of years from now, the story of humanity’s inevitable spread across the solar system will be a collection of engineering problems solved, some probably in heroic fashion. We’ve already tackled a lot of these problems in our first furtive steps into the wider galaxy. Our engineering solutions have taken humans to the Moon and back, but that’s as far as we’ve been able to send our fragile and precious selves.

While we figure out how to solve the problems keeping us trapped in the Earth-Moon system, we’ve sent fleets of robotic emissaries to do our exploration by proxy, to make the observations we need to frame the next set of engineering problems to be solved. But as we reach further out into the solar system and beyond, our exploration capabilities are increasingly suffering from communications bottlenecks that restrict how much data we can ship back to Earth.

We need to find a way to send vast amounts of data back as quickly as possible using as few resources as possible on both ends of the communications link. Doing so may mean turning away from traditional radio communications and going way, way up the dial and developing practical means for communicating with X-rays.

Continue reading “X-Rays Are The Next Frontier In Space Communications” →

New Part Day: Lynxmotion Smart Servos

Anyone who shops for robotics kits would have come across a few designed by Lynxmotion. They’ve been helping people build robots since 1995, from robot arm kits to hexapod chassis and everything in between. We would expect these people know their motors, so when they launched their own line of servo motors called Lynxmotion Smart Servos (LSS), it is worth spending a bit of time to look over what they offer.

While these new devices have a PWM mode compatible with classic remote control servos, unleashing their full power requires bidirectional communication over a serial bus. We’ve previously given an overview of three serial bus servos already on the market for comparison. A quick look at the $68-$100 price tags listed on Lynxmotion’s parent company RobotShop made it clear they do not intend to compete on price, so what interesting features do these new kids on the block have?

Digging into product documentation found some great details. Acceleration and deceleration rates are adjustable, which can help with smoother robot movement. There’s also an adjustable level of “stiffness” that adds some “give” (compliance) so a robot won’t have to be as stiff as… well, a robot!

Mechanically, the most interesting internal component is the magnetic position sensor. They are far more precise than potentiometers, but more importantly, they allow positioning anywhere within full 360 degrees. Many other serial bus servos are constrained to positions within an arc less than 360 degrees leaving a blind spot.

An interesting quirk of the LSS offerings is that the serial communication protocol uses human-readable text characters, so sending a number 255 means transmitting a three byte string ‘2’, ‘5’, and ‘5’ instead of single byte 0xFF. This would make debugging our custom robot code far easier, at the cost of reduced bandwidth efficiency and loss of checksum for detecting communication errors. It’s a trade-off that some robot builders would be happy to make, but others might not.

Externally, these servos have bountiful mounting options including some we didn’t know to ask for. Historically Lynxmotion kits have used a wide variety of servo mounting brackets, so they are motivated to make mechanical integration easy. The most novel offering is the ability to bolt external gears to the servo body. A set of 1:3 gears allow for gearing the servo up or down, or you can use a set of 1:1 gears for a compact gripper.

As you’d expect of servos in this price range, they all have metal gears, but they also have the ability to power the motor directly from a battery pack (a 3 cell lithium polymer is recommended). There are additional features, like an RGB LED for visual feedback, which we didn’t cover here so dig into the documentation for more. We look forward to seeing how these interesting little actuators perform in future robotics projects.

How-To: Mapping Server Hits With ESP8266 And WS2812

It has never been easier to build displays for custom data visualization than it is right now. I just finished one for my office — as a security researcher I wanted a physical map that will show me from where on the planet my server is being attacked. But the same fabrication techniques, hardware, and network resources can be put to work for just about any other purpose. If you’re new to hardware, this is an easy to follow guide. If you’re new to server-side code, maybe you’ll find it equally interesting.

I used an ESP8266 module with a small 128×32 pixel OLED display connected via an SSD1306 controller. The map itself doesn’t have to be very accurate, roughly knowing the country would suffice, as it was more a decorative piece than a functional one. It’s a good excuse to put the 5 meter WS2812B LED strip I had on the shelf to use.

The project itself can be roughly divided into 3 parts:

  1. Physical and hardware build
  2. ESP8266 firmware
  3. Server-side code

It’s a relatively simple build that one can do over a weekend. It mashes together LED strips, ESP8266 wifi, OLED displays, server-side code, python, geoip location, scapy, and so on… you know, fun stuff.

Continue reading “How-To: Mapping Server Hits With ESP8266 And WS2812” →

Twenty Five Years Since The End Of Commodore

This week marks the twenty-five year anniversary of the demise of Commodore International. This weekend, pour one out for our lost homies.

Commodore began life as a corporate entity in 1954 headed by Jack Tramiel. Tramiel, a Holocaust survivor, moved to New York after the war where he became a taxi driver. This job led him to create a typewriter repair shop in Bronx. Wanting a ‘military-style’ name for his business, and the names ‘Admiral’ and ‘General’ already taken, and ‘Lieutenant’ simply being a bad name, Tramiel chose the rank of Commodore.

Later, a deal was inked with a Czechoslovakian typewriter manufacture to assemble typewriters for the North American market, and Commodore Business Machines was born. Of course, no one cares about this pre-history of Commodore, for the same reason that very few people care about a company that makes filing cabinets. On the electronics side of the business, Commodore made digital calculators. In 1975, Commodore bought MOS, Inc., manufacturers of those calculator chips. This purchase of MOS brought Chuck Peddle to Commodore as the Head of Engineering. The calculators turned into computers, and the Commodore we know and love was born.

Continue reading “Twenty Five Years Since The End Of Commodore” →

The Stratolaunch Is Flying, But Can It Do Cargo?

The world’s largest aircraft is flying. Stratolaunch took to the skies in test flights leading up to its main mission to take rockets up to 20,000 feet on the first stage of their flight to space. But the Stratolaunch is a remarkable aircraft, a one-of-a-kind, and unlike anything ever built before. It can lift a massive 250 tons into the air, and it can bring it back down again.

By most measures that matter, the Stratolaunch is the largest aircraft ever flown. It has the largest wingspan of any aircraft, and it has the largest cargo capacity of any aircraft. In an industry that is grasping at interesting and novel approaches to spaceflight like rockoons and a small satellite launcher from a company whose CTO is still a junior in college, the Stratolaunch makes unexpected sense; this is a launch platform above the clouds, that can deliver a rocket to orbit, on time.

But the Stratolaunch is much more than that. This is an aircraft whose simple existence deserves respect. And, like others of its kind, the Antonov AN-225, the Spruce Goose, there is only one. Even if it never launches a rocket, the Stratolaunch will live on by the simple nature of its unique capabilities. But what are those capabilities? Is it possible for the Stratolaunch to serve as a cargo plane? The answer is more interesting than you think.

Continue reading “The Stratolaunch Is Flying, But Can It Do Cargo?” →

Teardown: Refuel Propane Tank Monitor

Regular Hackaday readers will know that the clearance section of your local big box retailer is a great place to pick up oddball gadgets and gizmos for dirt cheap. In an era where manufacturers are rushing to make their products “smart” whether they need to be or not, the occasional ideas which fail to gain traction are just the cost of doing business. If you keep an eye out, you’re almost guaranteed to see one of these Internet of Things rejects collecting dust on a back aisle, often selling for pennies on the dollar.

Case in point, the “Refuel” propane tank monitor from Wink. Though there’s also logos for Quirky and GE on the package as well, and even a picture of the guy who came up with the idea. Essentially what we have here is a digital scale that reports the current weight of your grill’s propane tank to your phone via the Internet. A trick we might consider a fairly simple hack with a load cell and an ESP8266 under normal circumstances, but as this is a commercial product with an MSRP of $49.99 USD, its naturally been over-complicated to the point of absurdity.

Of course, one could simply lift the propane tank and get a decent estimate of its contents; a trick mastered by weekend grill masters since time immemorial. But then you wouldn’t have to make an account with Wink, or go through the very strange process of attempting to configure the device by using the flashing light of your smartphone’s screen (seriously). All so you can check how much propane is left in your grill while you’re away from home. You know, as one does.

Frankly, it’s hard for me to imagine who would actually have purchased such a thing at full retail. But of course, that’s likely why I was able to pick it up for the princely sum of $5. At that price, we can’t afford not to take a peek into this gizmo from Wink, Quirky, GE, and Anthony from Boston.

Continue reading “Teardown: Refuel Propane Tank Monitor” →