optimization

24 Articles

Excuse Me, I Have To Feed The Computer

January 1, 2019 by 13 Comments

It is a staple of science fiction to see a brain in a jar or other container, maybe used as some sort of computer device. You are probably imagining a brain-powered supercomputer with a room full of humans with electrodes in their heads, or maybe some other primate. The reality though is it might be just a small dish full of single-celled amoeba.

Researchers from China and Japan have successfully made a lowly amoeba solve the traveling salesman problem for 8 cities. We’ll be honest. We don’t totally understand the value to it over traditional methods, but it does prove that you can compute with organic matter. This isn’t just any amoeba, though. It is a particular kind, Physarum polycephalum, that has an unusual property — it can shapeshift, at least to a limited degree. The tiny creature is just like us in that it tries to get things it likes and avoid things it doesn’t like. It likes food, but it doesn’t like light.

Provide food, and the tiny creature will spread out. Shine light on it, and it will retract. That’s the property used to solve the thorny problem, but before we look at how that works it helps to understand the problem it is trying to solve.

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Generative Design Algorithms Prepare For Space

November 17, 2018 by 14 Comments

NASA is famously risk-averse, taking cautious approaches because billions of taxpayer dollars are at stake and each failure receives far more political attention than their many successes. So while moving the final frontier outward requires adopting new ideas, those ideas must first prove themselves through a lengthy process of risk-reduction. Autodesk’s research into generative design algorithms has just taken a significant step on this long journey with a planetary lander concept.

It was built jointly with a research division of NASA’s Jet Propulsion Laboratory, the birthplace of many successful interplanetary space probes. This project got a foot in the door by promising 30% weight savings over conventional design techniques. Large reduction in launch mass is always a good way to get a space engineer’s attention! Mimicking mother nature’s evolutionary process, these algorithms output very organic looking shapes. This is a relatively new approach to design optimization under exploration by multiple engineering software vendors. Not just Autodesk’s “Generative Design” but also “Topology Optimization” in SolidWorks, plus others. Though these shapes appear ideally suited to 3D printing, Autodesk also had to prove their algorithm could work with more traditional fabrication techniques like 5-axis CNC mills.

This is leading-edge research technology though some less specialized, customer-ready versions are starting to trickle out of research labs. Starting with an exclusive circle: People with right tiers of SolidWorks license, the paid (not free) tier of Autodesk Fusion 360, etc. We’ve looked at another recent project with nontraditional organic shapes, and we’ve looked at generative designs used for their form as well as their function. This category of CAD tools hold a lot of promise, and we’re optimistic they’ll soon become widely accessible so we can all put them to good use in our earthbound projects.

Possibly even before they fly to another planet.

[via Engadget]

Weather Station Is A Tutorial In Low Power Design

November 4, 2018 by 15 Comments

Building your own weather station is a fun project in itself, but building it to be self-sufficient and off-grid adds another set of challenges to the mix. You’ll need a battery and a solar panel to power the station, which means adding at least a regulator and charge controller to your build. If the panel and battery are small, you’ll also need to make some power-saving tweaks to the code as well. (Google Translate from Italian) The tricks that [Danilo Larizza] uses in his build are useful for more than just weather stations though, they’ll be perfect for anyone trying to optimize their off-grid projects for battery and solar panel size.

When it comes to power conservation, the low-hanging fruit is plucked first. [Danilo] set the measurement intervals to as long as possible and put the microcontroller (a NodeMCU) to sleep in between. Removing the power from the sensors when the microcontroller was asleep was another easy step, but the device was still crashing overnight. Then he turned to a hardware solution and added a more efficient battery charger to the setup, which saved even more power. This is all the more impressive because the station communicates via WiFi which is notoriously difficult to run in low-power applications.

Besides the low power optimizations, the weather station itself is interesting for its relative simplicity. It could be built with things most of us have knocking around. Best of all, [Danilo] published the source code on his site, so most of the hard work has been done already. If you’re thinking he seems a little familiar, it’s because we’ve featured some of his projects before, like his cheap WiFi extender antenna and his homemade hybrid tube amplifier.

Learn To Optimize Code In Assembly… For Android

October 30, 2018 by 11 Comments

When programming a microcontroller, there are some physical limitations that you’ll come across much earlier than programming a modern computer, whether that’s program size or even processor speed. To make the most use of a small chip, we can easily dig into the assembly language to optimize our code. On the other hand, modern processors in everyday computers and smartphones are so fast and have so much memory compared to microcontrollers that this is rarely necessary, but on the off-chance that you really want to dig into the assembly language for ARM, [Uri Shaked] has a tutorial to get you started.

The tutorial starts with a “hello, world” program for Android written entirely in assembly. [Uri] goes into detail on every line of the program, since it looks a little confusing if you’ve never dealt with assembly before. The second half of the program is a walkthrough on how to actually execute this program on your device by using the Android Native Deveolpment Kit (NDK) and using ADB to communicate with the phone. This might be second nature for some of us already, but for those who have never programmed on a handheld device before, it’s worthwhile to notice that there are a lot more steps to go through than you might have on a regular computer.

If you want to skip the assembly language part of all of this and just get started writing programs for Android, you can download an IDE and get started pretty easily, but there’s a huge advantage to knowing assembly once you get deep in the weeds especially if you want to start reverse engineering software or bitbanging communications protocols. And if you don’t have an Android device handy to learn on, you can still learn assembly just by playing a game.

Learning Software In A Soft Exosuit

April 16, 2018 by 2 Comments

Wearables and robots don’t often intersect, because most robots rely on rigid bodies and programming while we don’t. Exoskeletons are an instance where robots interact with our bodies, and a soft exosuit is even closer to our physiology. Machine learning is closer to our minds than a simple state machine. The combination of machine learning software and a soft exosuit is a match made in heaven for the Harvard Biodesign Lab and Agile Robotics Lab.

Machine learning studies a walker’s steady gait for twenty periods while vitals are monitored to assess how much energy is being expended. After watching, the taught machine assists instead of assessing. This type of personalization has been done in the past, but the addition of machine learning shows that the necessary customization can be programmed into each machine without a team of humans.

Exoskeletons are no stranger to these pages, our 2017 Hackaday Prize gave $1000 to an open-source set of robotic legs and reported on an exoskeleton to keep seniors safe.

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Optimizing Linux For Slow Computers

January 19, 2017 by 100 Comments

It’s interesting, to consider what constitutes a power user of an operating system. For most people in the wider world a power user is someone who knows their way around Windows and Microsoft Office a lot, and can help them get their print jobs to come out right. For those of us in our community, and in particular Linux users though it’s a more difficult thing to nail down. If you’re a LibreOffice power user like your Windows counterpart, you’ve only really scratched the surface. Even if you’ve made your Raspberry Pi do all sorts of tricks in Python from the command line, or spent a career shepherding websites onto virtual Linux machines loaded with Apache and MySQL, are you then a power user compared to the person who knows their way around the system at the lower level and has an understanding of the kernel? Probably not. It’s like climbing a mountain with false summits, there are so many layers to power usership.

So while some of you readers will be au fait with your OS at its very lowest level, most of us will be somewhere intermediate. We’ll know our way around our OS in terms of the things we do with it, and while those things might be quite advanced we’ll rely on our distribution packager to take care of the vast majority of the hard work.

Linux distributions, at least the general purpose ones, have to be all things to all people. Which means that the way they work has to deliver acceptable performance to multiple use cases, from servers through desktops, portable, and even mobile devices. Those low-level power users we mentioned earlier can tweak their systems to release any extra performance, but the rest of us? We just have to put up with it.

To help us, [Fabio Akita] has written an excellent piece on optimizing Linux for slow computers. By which he means optimising Linux for desktop use on yesterday’s laptop that came with Windows XP or Vista, rather than on that ancient 486 in the cupboard. To a Hackaday scribe using a Core 2 Duo, and no doubt to many of you too, it’s an interesting read.

In it he explains the problem as more one of responsiveness than of hardware performance, and investigates the ways in which a typical distro can take away your resources without your realising it. He looks at RAM versus swap memory, schedulers, and tackles the thorny question of window managers head-on. Some of the tweaks that deliver the most are the easiest, for example the Great Suspender plugin for Chrome, or making Dropbox less of a hog. It’s not a hardware hack by any means, but we suspect that many readers will come away from it with a faster machine.

If you’re a power user whose skills are so advanced you have no need for such things as [Fabio]’s piece, share your wisdom on sharpening up a Linux distro for the rest of us in the comments.

Via Hacker News.

Header image, Tux: Larry Ewing, Simon Budig, Garrett LeSage [Copyrighted free use or CC0], via Wikimedia Commons.

Running Intel TBB On A Raspberry Pi

December 1, 2016 by 17 Comments

The usefulness of Raspberry Pis seems almost limitless, with new applications being introduced daily and with no end in sight. But, as versatile as they are, it’s no secret that Raspberry Pis are still lacking in pure processing power. So, some serious optimization is needed to squeeze as much power out of the Raspberry Pi as possible when you’re working on processor-intensive projects.

This simplest way to accomplish this optimization, of course, is to simply reduce what’s running down to the essentials. For example, there’s no sense in running a GUI if your project doesn’t even use a display. Another strategy, however, is to ensure that you’re actually using all of the available processing power that the Raspberry Pi offers. In [sagiz’s] case, that meant using Intel’s open source Threading Building Blocks to achieve better parallelism in his OpenCV project.

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