MOSAiC Project Freezes A Boat In The Arctic Ice Pack For Science

November 4, 2020 by 5 Comments

Just over a fortnight ago, RV Polarstern, a German research vessel, sailed back into port, heralding the end of the largest Arctic research project ever undertaken. The MOSAiC expedition, short for Multidisciplinary drifting Observatory for the Study of Arctic Climate, spent a full year running experiments to measure conditions at the North Pole, and research how the unique Arctic climate is being affected by human activity.

Unprecedented In Size And Scope

The operation was regularly resupplied by visits from other icebreakers, bringing equipment, food, and fresh personnel. Alfred-Wegener-Institut / Jan Rohde (CC-BY 4.0)

With a budget exceeding €140 million, and with over 300 scientists attached to the project, the expedition aimed to study a full year-long ice cycle in the Arctic region. To achieve this, the research vessel of the project, RV Polarstern, was navigated into an ice floe, and allowed to freeze in and drift with the ice pack. As the seasons progressed, the vessel drifted with the sea ice across the polar region. Along the way, a series of rotating research teams set up equipment on the ice and took regular measurements, investigating several scientific focus areas. Different groups observed atmospheric conditions and the sea ice itself, with researchers also focusing on biogeochemistry, the ocean, and the ecosystems in the area.

Icebreakers were used to transport goods and personnel to the RV Polarstern over the duration of the mission. The project faced issues in spring, as a pre-planned changeover executed by aircraft had to be abandoned due to restrictions brought about by the COVID-19 pandemic. Instead, this was also executed by ship, with the Polarstern temporarily leaving the ice to rendezvous with RV Sonne and RV Maria S. Merian for the changeover of approximately 100 crew and to pick up provisions. The detour took three weeks, but didn’t have any major negative impacts on the mission. Continue reading “MOSAiC Project Freezes A Boat In The Arctic Ice Pack For Science” →

Scratch Built 3D Printer Goes Big

November 4, 2020 by 24 Comments

There was a time, not so very long ago, that buying a reliable 3D printer was a fairly expensive proposition. Many chose to build their own printer instead, and for a few years, we were flooded with very impressive custom designs. But as you might expect, with the prices on decent 3D printers now having hit rock bottom, the custom builds have largely dried up.

Arguably, the only reason you’d build rather than buy in 2020 is if you want something very specific. Which is precisely how [Joshendy] ended up building the Big F… Printer or BFP. No doubt the F stands for Fun, or Friendly. Either way, it’s certainly something special. With a 300 mm³ build volume and heavy-duty Z axis, this fully enclosed CoreXY machine is ready to handle whatever he throws at it.

It did take [Joshendy] a few attempts to get everything the way he wanted though. In fact, the prototype for the machine wasn’t even CoreXY, it started as an H-Bot. In his write-up he goes over the elements of the BFP did that didn’t quite live up to his expectations, and what he replaced them with. So when wobbly leadscrews and a knock-off V6 hotend both left something to be desired, they ended up getting replaced with ball screws and an authentic E3D Hemera, respectively.

To control this monster, [Joshendy] is using OctoPrint on a Raspberry Pi and a BigTreeTech SKR Pro running Klipper. OctoPrint gives him the ability to control and monitor the printer remotely, complete with a camera mounted inside the enclosure to keep an eye on things, while the Klipper firmware on the SKR board pushes all the computationally expensive aspects of 3D printing onto the vastly more powerful ARM chip in the Pi. The end result is faster and more accurate control of the steppers through the TMC2130 drivers than would be possible otherwise.

If you don’t mind tinkering, a cheap entry-level desktop 3D printer is good enough for most of hackers and makers. If you need something more capable or more reliable, there’s always higher-end options from the likes of Prusa and Ultimaker. Very few people need to build something as serious as the BFP, but when the do, we’re glad they send them our way.

Continue reading “Scratch Built 3D Printer Goes Big” →

Wheels Or Legs? Why Not Both?

November 4, 2020 by 28 Comments

Out of the thousands of constraints and design decisions to consider when building a robot, the way it moves is perhaps one of the most fundamental. The method of movement constrains the design and use case for the robot perhaps more than any other parameter. A team of researchers at Texas A&M led by [Kiju Lee] is trying to have their cake and eat it too by building a robot with wheels that transform into legs, known as a-WaLTR (Adaptable Wheel-and-Leg Transformable Robot).

a-WaLTR was designed to conquer one of wheeled robots’ biggest obstacles: stairs. By adding a bit of smarts to determine whether a given terrain is better handled by wheels or legs, a-WaLTR can convert its segmented wheels into simple legs. Rather than implemented complex and error-prone articulated legs, the team stuck with robust appendages that remind us a little of whegs.

The team will show off their prototype at DARPA OFFSET Sprint-5 in February 2021, which is a program focused on building robots that can form adaptive human-swarm teams.

Thanks to the rise of 3D printers and hobbyist electronics there are more open-source experimental robot designs than ever. We’ve seen smaller versions of the famous Boston Dynamics’ Spot as well as simpler quadruped bots with more servos. a-WaLTR isn’t the first transforming robot we’ve seen, but we’re looking forward to seeing more unique takes on robotic locomotion in the future.

Thanks to [Qes] for sending this one in!

“Brain In A Vat” 6502

November 3, 2020 by 39 Comments

The 6502 was a revolutionary processor for its time. Offered at a small fraction of the cost of other processors available when it was released, it became adopted in such iconic computers at the Atari 2600, the Apple II, the NES, and the Commodore 64. For that reason it’s still extremely popular among retrocomputing enthusiasts who will often go to great lengths to restore these computers or build them from scratch. [jamesbowman] had an idea to build a 6502-based computer with the processor only, leaving the rest of the computer up to an FPGA.

He describes the system as a “brain in a vat” since a real 6502 is used as the “brain” and all other functions are passed off to the FPGA. In his build he uses an FPGA board with built-in graphics abilities, but the truly interesting part of this build is how the FPGA handles memory. If a particular value is placed on the data bus of the 6502, it loops forever through the entire memory and executes all of the instructions it finds. This saved a lot of time getting this system up and running, and he is able to demonstrate it by showing a waveform on the video output of the device.

Of course you can take an FPGA and emulate an entire computer based on a 6502, but using the actual silicon in a build like this really ensures that the user can learn and understand the hardware involved without some of the other tedium of doing things such as converting old video signals to HDMI for example. It’s a great take on retrocomputing that we expect to see more of in the future.

Make Some Noise Or Simulate It, At Least

November 3, 2020 by 6 Comments

Noise is a fact of life, especially in electronic circuits. But on our paper schematics and just as often our simulations, there is no noise. If you are blinking an LED on a breadboard, you probably don’t care. But if you are working on something meatier, handling electrical noise gracefully is important and simulation can help you. [Ignacio de Mendizábal] has a great piece on simulating EMC filters using LTSpice that can get you started.

There are many ways of classifying noise and [Ignacio] starts with common-mode versus differential noise, where common-mode is noise with current flowing in the same direction without regard to the circuit’s normal operation, and differential noise having currents that flow in the opposite direction of normal current flow.

Continue reading “Make Some Noise Or Simulate It, At Least” →

E-Paper Weather Display Is A Great Base To Build From

November 3, 2020 by 26 Comments

As e-paper modules have become more affordable, we’ve started to see them pop up more and more in hacker projects. It used to be that you had to force a second-hand Kindle to do your bidding, but now you can buy just the screen itself complete with a header to plug right into your Raspberry Pi. It will still cost you as much as a used Kindle…but at least it comes with some documentation and there are Python libraries to talk to it.

But where to start? If you need some inspiration, and perhaps a little source code, this very slick weather display put together by [James Howard] is a great as baseline. Not that it really needs any additional refinement, as we think it already looks gorgeous. But rather than starting from scratch for your own project, it would be much easier to graft some additional functionality onto his code.

A lot of that has to do with how concise and well commented his code is. We’ve seen enough of these projects to know the kind of spaghetti that’s often running on the backend, but there’s none of that here. [James] assembles the display using the powerful Pillow graphics library, which lets you draw primitives and drop in text and icons with just a couple lines of code.

Once all the data is plugged in, the entire screen is saved as an image file which is then opened up on the e-paper display. Even if you aren’t a Python expert, you should be able to understand what’s happening and how to bend it to your will.

We’ve always had high hopes for electronic paper, and it seems the technology might finally be hitting critical mass. While it’s still a bit expensive, we’ve started seeing it pop up in unexpected places to great effect. Hopefully projects like this one will inspire others to take the B&W plunge.

Computer Vision Maps Christmas Lights

November 3, 2020 by 27 Comments

There’s a small but dedicated group of folks out there who spend all year planning their Christmas decorations. These aren’t simple lawn ornaments or displays, either, but have evolved into complex lightning performances that require quite a bit of computer control. For some things, hooking up a relay to a microcontroller can get the job done, but [Andy] has turned to computer vision to solve some of the more time-consuming aspects of these displays.

Specifically, [Andy] has a long string of programmable RGB LED lights to wrap around a Christmas tree, but didn’t want to spend time manually mapping out each light’s location. So he used OpenCV to register the locations of the LEDs from three different camera angles, and then used a Python script to calculate their position in the 3D space. This means that he will easily be able to take the LEDs down at the end of the holidays and string them back up next year without having to do the tedious manual mapping ever again.

While [Andy] notes that he may have spent more time writing the software to map out the LEDs than manually doing it himself, but year-after-year it may save him a lot of time and effort, not to mention the benefits of a challenge like writing this software in the first place. If you want to get started on your own display this year, all you really need is some lights and a MIDI controller.