Lasercut Gears – A Learning Experience

August 2, 2018 by 7 Comments

Lasercutters are fantastic tools: they’re highly useful for making flat things, or even flat things that you later bend! This makes them particularly well suited for making gears out of flat stock. [sharvfish] needed to get his hands dirty with producing some gears for his automaton, and decided to share what he learned in the process.

The gears in question are cut out of MDF board, which is readily usable on all but the feeblest lasercutters you’ll find in the average makerspace. The first problem faced was when producing gears with low tooth counts – depending on the exact geometry used, teeth with lower counts can tend to jam easily. For [sharvfish]’s gears, 6 teeth seems to be just a touch too small to work well. Other issues cropped up around the kerf of the cuts affecting the gear mesh and the use of pins to improve the coupling of the gears to the shaft, which [sharvfish] expands upon in the video. There’s also a cheeky cephalopod cameo, too.

It’s always interesting to see the unique challenges faced in the undertaking of a project; we could see six more lasercut projects this week, and we’d likely see six unique problems the builders faced as well. It’s a great insight into the build process and it’s great when makers share their journey as well as the finished product. Video after the break.

Wondering what lasercut gears can do for you? Check out this build that rotates an entire television.

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The Photo Lab That Flew To The Moon

August 2, 2018 by 12 Comments

When planning a trip by car these days, it’s pretty much standard practice to spin up an image of your destination in Google Maps and get an idea of what you’re in for when you get there. What kind of parking do they have? Are the streets narrow or twisty? Will I be able to drive right up, or will I be walking a bit when I get there? It’s good to know what’s waiting for you, especially if you’re headed someplace you’ve never been before.

NASA was very much of this mind in the 1960s, except the trip they were planning for was 238,000 miles each way and would involve parking two humans on the surface of another world that we had only seen through telescopes. As good as Earth-based astronomy may be, nothing beats an up close and personal look, and so NASA decided to send a series of satellites to our nearest neighbor to look for the best places to land the Apollo missions. And while most of the feats NASA pulled off in the heyday of the Space Race were surprising, the Lunar Orbiter missions were especially so because of how they chose to acquire the images: using a film camera and a flying photo lab.

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Crowdfunding: !Sinclair !ZX Vega To Lose The Sinclair Name

August 2, 2018 by 5 Comments

It’s not a good time to be a backer of the crowdfunded Sinclair ZX Vega retro console. After raising a record sum on Indiegogo, a long series of broken promises and missed dates, and a final loss of patience from the crowdfunding site, it has emerged that the owner of the Sinclair and ZX brands is to withdraw the right to use them from the console.

The Vega itself should have been a reasonable proposition, a slick handheld running the FUSE Spectrum emulator rather than Z80 hardware, and from Retro Computers Limited, a company that boasted a 25% ownership from Sinclair Research and thus Sir Clive himself. The sorry tale of its mishandling will probably in time provide enough information for a fascinating book or documentary in itself, but one thing that has come to light in the BBC’s reporting is the fate of those Sinclair brands. They famously passed to Amstrad in the 1980s, a move that gave us the Spectrum +2 and +3 with decent keyboards and built-in tape and disk drives, but long after the last Spectrum had rolled off the production line they passed with Amstrad’s set-top-box business to the satellite broadcaster Sky, who are now responsible for pulling the plug.

This is a general news story as much as a hardware story as there is little by way of a hack to be found beyond the realisation that you could almost certainly roll your own with a Raspberry Pi, a copy of FUSE, and a 3D-printed case. But it’s a fitting follow-up to our previous reporting, and unless something unexpected happens in the Retro Computers boardroom it’s probably the last we’ll hear of the product. In an unexpected twist though they are reported to have shipped a few Vegas to backers in recent days, and we’ll leave the final word to the BBC’s quote from [David Whitchurch-Bennett], one of those recipients.

“The buttons are absolutely awful, You have to press so hard and they intermittently stop working unless you apply so much pressure.”

From where we’re sitting, remembering the dubious quality of some of the keyboards on original Spectrum products, we think that it might have more in common with the original than anyone is willing to admit.

Shell Script Synthesizer Knocks Your SoX Off

August 2, 2018 by 5 Comments

Sound eXchange, or SoX, the “Swiss Army knife of audio manipulation” has been around for as long as the Linux kernel, and in case you’re not familiar with it, is a command line tool to play, record, edit, generate, and process audio files. [porkostomus] was especially interested about the generating part, and wrote a little shell script that utilizes SoX’s built-in synthesizer to compose 8-bit style music.

The script comes with a simple yet straightforward user interface to record the lead and bass parts into a text file, and play them back later on. Notes from C2 to C5 are currently supported, and are mapped to the keyboard in a two-row piano layout. The output file format itself is just a plain text listing of the played note, wave form, and note length. This lets you easily edit the song or even generate it from an alternative source, for example MIDI. Also note that there are no initial audio files required here, SoX will generate them as needed.

Admittedly, the command line interface may not be the most convenient way to create music, but nevertheless, it is a way — and that is [porkostomus]’s main mission here. Also, SoX is fun — and versatile, you can apply its audio effects even on images, or decode strange signals sent from a helicopter with it.

Raspberry Pi On The Go Powers Car System

August 1, 2018 by 9 Comments

Most new cars have GPS, rear cameras, and all the other wonders an on-board system can bring. But what if you have an old car? [Fabrice Aneche] has a 2011 vehicle, and wanted a rearview camera. He started with a touch screen, a Raspberry Pi 3, and a camera. But you know how these projects take on a life of their own. So far, the project has two entries in his blog.

It wasn’t long before he couldn’t resist the urge to add a GPS. But that’s no fun without maps. Plus you need turn-by-turn directions. [Fabrice] did a lot of the user interface using Qt5 and QML. He started out running it with X11 but that was slow. It turns out though that Qt5 can drive the Pi’s video directly without using X11, so that’s what he wound up doing. The code that isn’t in QML — mainly dealing with the GPS location — is written in Go, while the code for MOCS (My Own Car System) is on GitHub.

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Hanky-Deprived Drones Taste Whale Snot For Science

August 1, 2018 by 5 Comments

A whole world of biomass floats in the boogers of a whale’s exhaust, and it’s a biologist’s dream to explore it. Whale snot carries everything from DNA samples to hormone signatures. But getting close enough to a surfacing whale for long enough to actually sample this snot turns out to be a nightmare when done by boat. Researcher [Iain Kerr] and a team from Olin College of Engineering thought, why not use a drone instead? Behold, the Snotbot was born!

Snotbot is essentially a petri-dish-equipped commercial drone that users can pilot into the exhaust of a whale to collect samples before the cetacean dives back under. After 7 missions and over 500 collected samples, Snotbot is putting-to-rest years of frustration from researchers anticipating their next chance for a shot of snot. Along the way, the team have also leveraged it to image the whale’s fluke (a fingerprint equivalent), drop underwater mics, and collect poo samples. As opposed to darts, Snotbot is non-invasive, and the whales don’t seem to mind (or even notice) who’s downstream of their boogers.

Drones are almost ubiquitous at this point in our lives–to the point where they now fall under regulations by the US government. With so many of us building our own drones at home, it’s wonderful to see groups starting to ask the next question: cool drone; now what? With reliable drones at prices that are within reach for the everyday citizen, we’re excited that we will see dozens of applications that leverage this new skyward-bound platform over the coming years. If you can’t wait, have a quick look back in time, where drones are doing maritime deliveries and blowing up debris.

Quadcopter Hardware Gets Classic Lake Bed Test

August 1, 2018 by 6 Comments

You’d be hard pressed to find an aircraft that wasn’t designed and tested without extensive use of simulation. Whether it’s the classic approach of using a scale model in a wind tunnel or more modern techniques such as computational fluid dynamics, a lot of testing happens before any actual hardware gets bolted together. But at some point the real deal needs to get a shakedown flight, and historically a favorite testing ground has been the massive dry lake beds in the Western United States. The weather is always clear, the ground is smooth, and there’s nobody for miles around.

Thanks to [James] and [Tyler] at Propwashed, that same classic lake bed approach to real-world testing has now been brought to the world of high performance quadcopter gear. By mounting a computer controlled thrust stand to the back of their pickup truck and driving through the El Mirage dry lake bed in the Mojave Desert, they were able to conduct realistic tests on how different propellers operate during flight. The data collected provides an interesting illustration of the inverse relationship airspeed has with generated thrust, but also shows that not all props are created equal.

The first post in the series goes over their testing set-up and overall procedure. On a tower in the truck’s bed a EFAW 2407 2500kV motor was mounted on a Series 1520 thrust stand by RCBenchmark. This stand connects to the computer and offers a scripted environment which can be used to not only control the motor but monitor variables like power consumption, RPM, and of course thrust. While there was some thought given to powering the rig from the truck’s electrical system, in the end they used Turnigy 6000mAh 4S battery packs to keep things simple.

A script was written for the thrust stand which would ramp the throttle from 0% up to 70% over 30 seconds, and then hold it at that level for 5 seconds. This script was run when the truck was at a standstill, and then repeated with the truck travelling at increasingly faster speeds up to 90 MPH. This procedure was repeated for each of the 15 props tested, and the resulting data graphed to compare how they performed.

The end result was that lower pitch props with fewer blades seemed to be the best overall performers. This isn’t a huge surprise given what the community has found through trial and error, but it’s always good to have hard data to back up anecdotal findings. There were however a few standout props which performed better at high speeds than others, which might be worth looking into if you’re really trying to push the envelope in terms of airspeed.

As quadcopters (or “drones”, if you must) have exploded in popularity, we’re starting to see more and more research and experimentation done with RC hardware. From a detailed electrical analysis of hobby motors to quantifying the latency of different transmitters.