Pistons being lasered into existence. Image via The Drive
These pistons are printed from high-purity aluminium alloy powder that was developed by German auto parts manufacturer Mahle. Porsche is having these produced by Mahle in partnership with industrial machine maker Trumpf using the laser metal fusion (LMF) process. It’s a lot like selective laser sintering (SLS), but with metal powder instead of plastic.
The machine dusts the print bed with a layer of powder, and then a laser melts the powder according to the CAD file, hardening it into shape. This process repeats one layer at a time, and supports are zapped together wherever necessary. When the print job is finished, the pistons are machined into their shiny final form and thoroughly tested, just like their cast metal cousins have been for decades. Continue reading “Porsche’s Printed Pistons Are Powerful And Precise”→
The jet engine has a long and storied history. Its development occurred spontaneously amongst several unrelated groups in the early 20th Century. Frank Whittle submitted a UK patent on a design in 1930, while Hans von Ohain begun exploring the field in Germany in 1935. Leading on from Ohain’s work, the first flight of a jet-powered aircraft was in August 27, 1939. By the end of World War II, a smattering of military jet aircraft had entered service, and the propeller was on the way out as far as high performance aviation is concerned.
China’s development of ballpoint pen tips was a national news story in 2017. Source: Xinhua
In the age of the Internet and open source, technology moves swiftly around the world. In the consumer space, companies are eager to sell their product to as many customers as possible, shipping their latest wares worldwide lest their competitors do so first. In the case of products more reliant on infrastructure, we see a slower roll out. Hydrogen-powered cars are only available in select regions, while services like media streaming can take time to solve legal issues around rights to exhibit material in different countries. In these cases, we often see a lag of 5-10 years at most, assuming the technology survives to maturity.
In most cases, if there’s a market for a technology, there’ll be someone standing in line to sell it. However, some can prove more tricky than others. The ballpoint pen is one example of a technology that most of us would consider quaint to the point of mediocrity. However, despite producing over 80% of the world’s ballpoint pens, China was unable to produce the entire pen domestically. Chinese manufactured ballpoint tips performed poorly, with scratchy writing as the result. This attracted the notice of government officials, which resulted in a push to improve the indigenous ballpoint technology. In 2017, they succeeded, producing high-quality ballpoint pens for the first time.
The secrets to creating just the right steel, and manipulating it into a smooth rolling ball just right for writing, were complex and manifold. The Japanese, German, and Swiss companies that supplied China with ballpoint tips made a healthy profit from the trade. Sharing the inside knowledge on how it’s done would only seek to destroy their own business. Thus, China had to go it alone, taking 5 years to solve the problem.
There was little drive for pen manufacturers to improve their product; the Chinese consumer was more focused on price than quality. Once the government made it a point of national pride, things shifted. For jet engines, however, it’s somewhat of a different story.
If you take to the outdoors for your exercise, rather than walking the Sisyphusian stair machine, it’s nice to grab some GPS-packed electronics to quantify your workout. [Bunnie Huang] enjoys paddling the outrigger canoe through the Singapore Strait and recently figured out how to unpack and visualize GPS data from his own Garmin watch.
By now you’ve likely heard that Garmin’s systems were down due to a ransomware attack last Thursday, July 23rd. On the one hand, it’s a minor inconvenience to not be able to see your workout visualized because of the system outage. On the other hand, the services have a lot of your personal data: dates, locations, and biometrics like heart rate. [Bunnie] looked around to see if he could unpack the data stored on his Garmin watch without pledging his privacy to computers in the sky.
These IoT devices are by all accounts amazing, listening for satellite pings to show us how far and how fast we’ve gone on web-based interfaces that are sharable, searchable, and any number of other good things ending in “able”. But the flip side is that you may not be the only person seeing the data. Two years ago Strava exposed military locations because of an opt-out policy for public data sharing of exercise trackers. Now Garmin says they don’t have any indications that data was stolen in the ransomware attack, but it’s not a stretch to think there was a potential there for such a data breach. It’s nice to see there are Open Source options for those who want access to exercise analytics and visualizations without being required to first hand over the data.
There’s no denying that the reach and variety of internet radio is super cool. The problem is that none of the available interfaces really give the enormity of the thing the justice it deserves. We long for a more physical and satisfying interface for tuning in stations from around the globe, and [Jude] has made just the thing.
The other encoder is on the left side of the globe, and reads whatever latitude is focused in the reticle. Both encoder are connected to a Raspberry Pi 4, though if you want to replicate this open-source project using the incredibly detailed instructions, he says a Raspberry Pi 3 B+ will work, too.
In the base there’s an LCD that shows the coordinates, the city, and the station ID. Other stations in the area are tune-able with the jog wheel on the base. There’s also an RGB LED that blinks red while the station is being tuned in, and turns green when it’s done. We totally dig the clean and minimalist look of this build — especially the surprise transparent bottom panel that lets you see all the guts.
There are three videos after the break – a short demo that gives you the gist of how it works, a longer demonstration, and a nice explanation of absolute rotary encoders. Those are just the tip of the iceberg, because [Jude] kept a daily vlog of the build.
For those getting started with 3D printers, thermoplastics such as ABS and PLA are the norm. For those looking to produce parts with some give, materials like Ninjaflex are most commonly chosen, using thermoplastic polyeurethane. Until recently, it hasn’t been possible to 3D print latex rubber. However, a team at Virginia Tech have managed the feat through the combination of advanced printer hardware and some serious chemistry.
Sample cubes printed with the new process. Note the clarity of the sample at the top right.
The work was primarily a collaboration between [Phil Scott] and [Viswanath Meenakshisundaram]. After initial experiments to formulate a custom liquid latex failed, [Scott] looked to modify a commercially available product to suit the project. Liquid latexes are difficult to work with, with even slight alterations to the formula leading the solution to become unstable. Through the use of a molecular scaffold, it became possible to modify the liquid latex to become photocurable, and thus 3D printable using UV exposure techniques.
The printer side of things took plenty of work, too. After creating a high-resolution UV printer, [Meenakshisundaram] had to contend with the liquid latex resin scattering light, causing parts to be misshapen. To solve this, a camera was added to the system, which visualises the exposure process and self-corrects the exposure patterns to account for the scattering.
It’s an incredibly advanced project that has produced latex rubber parts with advanced geometries and impressive mechanical properties. We suspect this technology could be developed quickly in the coming years to produce custom rubber parts with significant strength. In the meantime, replicating flexible parts is still possible with available filaments on the market.
When [Deadline] couldn’t find a replacement control module for his Masterbuilt electric smoker, he could have just tossed the thing in the trash. Instead, he decided to come up with his own system to take over for the smoker’s original brain. Basing it around the nearly 40 year old Commodore 64 probably wouldn’t have been our first choice, but it’s hard to argue with the end result.
Connectors to control the smoker’s hardware.
At the most basic level, controlling an electric smoker like this only requires a temperature sensor, a relay to control the heating element, and something to get those two devices talking to each other. But for the best results you’ll also want some kind of a timer, and an easy way to change the target temperature on the fly. Connecting the relay and temperature sensor up to the back of the C64 was easy enough, all he had to do was write the BASIC code to glue it all together.
This hack was made considerably easier thanks to the fact that the Masterbuilt’s original controller interfaced with the smoker by way of a couple relatively well documented connectors. So instead of having to mess with any of the mains voltage electronics, he simply had to bring a wire in the connector high to fire up the smoker’s heating element. This bodes well for anyone looking to replace the controller in a similar smoker, with a C64 or otherwise.
Put simply, the goal of any reusable booster is to reduce the cost of getting a payload into space. The comparison is often made to commercial aviation: if you had to throw away the airliner after every flight, nobody could afford the tickets. The fact that the plane can be refueled and flown again and again allows operators to amortize its high upfront cost.
In theory, the same should hold true for orbital rockets. With enough flight experience, you can figure out which parts of the vehicle will need replacement or repair, and how often. Assuming the fuel is cheap enough and the cost of refurbishment doesn’t exceed that of building a new one, eventually the booster will pay for itself. You just need a steady stream of paying customers, which is hardly a challenge given how much we rely on our space infrastructure.
But there’s a catch. For the airliner analogy to really work, whatever inspections and repairs the rocket requires between missions must be done as quickly as possible. The cost savings from reuse aren’t nearly as attractive if you can only fly a few times a year. The key to truly making space accessible isn’t just building a reusable rocket, but attaining rapid reusability.
Which is precisely where SpaceX currently finds themselves. Over the years they’ve mastered landing the Falcon 9’s first stage, and they’ve even proven that the recovered boosters can be safely reused for additional flights. But the refurbishment process is still fairly lengthy. While their latest launch officially broke the record for fastest reflight of a space vehicle that had previously been set by Space Shuttle Atlantis, there’s still a lot of work to be done if SpaceX is ever going to fly their rockets like airplanes.
