Science Projects

Machine PCB assembly in the USA Skills Offered / Adafruit Jobs Board We are offering affordable PCB assembly in the good old USA. We purchased a MannCorp MC385-1V1 pick-and-place assembly machine for our retail and wholesale operations late last year, but our particular market will be slow for the next 6 months. We’re looking for an excuse to keep this wonderful pick-and-place machine running over the summer (it’s a shame to have it sitting there collecting dust). We are hoping to find designers who have prototype, small batch, or low to medium volume needs. Please contact us if you are looking for machine PCB assembly in the USA. Rates are negotiable – we don’t have a rate sheet because we’re new to doing contract work and it seems that every job is different. We have placed SMT’s down to and below 19 mil pitch. Machine can easily place 0402′s and 010005′s (we purchased all the bells and whistles for this machine). We can pick up reel parts, cut tape parts, waffle packs, loose parts. Our stencil printer is a manual stencil printer, we have printed SMT’s down to and below 19 mil pitch. We can handle single boards, simple matrix panels or complicated matrix panels up to about 14″ x 12″. We can do lead and lead-free. We are rather informal so we feel we are a good fit for designers who are on a budget but don’t want to send their pieces overseas. Looking forward to working with you on your project. Learn More

We love the look, and most especially the gait, of [Theo Jansen's] walker designs. We don’t fully understand them or the math behind them. But that could change if we spend enough time studying [Aaron Birenboim's] body of work. He wants to incorporate the legs in a project so he’s been trying to optimize the Jansen leg design. The calculations are delivered in a source code package available from his site. To make heads or trails out of the numbers you need a way to visualize them. He has provided that as well in the form of a MATLAB script which shows leg piece design and can even spit out an animated .gif file of the virtual legs in motion. If you have no idea what we’re talking about make sure to check out [Jansen's] original creations. We’re also excited to read more about the Klann and Ghassaei linkage designs which [Aaron] talks about in his post. Filed under: 3d Printer hacks

Born on May 21, 1799: Mary Anning, fossil collector who found her first complete skeleton, an ichthyosaur, as a young girl in Lyme Regis. What "type" of fossils did Mary Anning find—and why? In the new "Fantastic Fossilization! Discover the Conditions For Creating the Best Cast Fossils" geology Project Idea, students learn about four types of fossils and get hands-on making cast fossils in different kinds of soil. Fossils and the possibility of finding something prehistoric encased in soil or rock may excite students of all ages (and from an early age!). Whether your student's interest in fossils and paleontology and archaeology stems from a passion for dinosaurs or as an offshoot of fascination with King Tutankhamun, Mary Anning, as a female fossil hunter, is a great person in science history for students to know about. Introduce students to Mary Anning's story—and the world of fossils and paleontology— with books like these, many of which may be available at your school or local library: Looking for books for older or adult readers? Consider The Fossil Hunter: Dinosaurs, Evolution, and the Woman Whose Discoveries Changed the World (Macmillan Science) (biography) or Tracy Chevalier's New York Times bestseller, Remarkable Creatures: A Novel (fictionalized account). Hands-on Fossil Exploration The new hands-on "Fantastic Fossilization! Discover the Conditions For Creating the Best Cast Fossils" geology project lets students explore "cast" fossils. Cast fossils are one of four types of fossils. As students will discover by doing the science experiment and making their own cast fossils using shells and plaster of Paris, certain types of soil are more suitable for preserving cast fossils than others. In addition to offering an excellent independent science project, this idea can be great for classes or family exploration! Making Science Connections Our "today in Science History" posts make students, teachers, and parents aware of important discoveries and scientists in history and help connect science history to hands-on K-12 science exploration that students (and families) can do today. To follow along, join us at Facebook or at Google+. These frequent science history tidbits can be great for class, dinner, or car-ride discussion!

Years ago we covered using thermite to destroy a hard drive. The idea is that if you melt through the platters, the data is completely unrecoverable.  There are tons of videos of people doing this, but they all have a similar format. There’s a hard drive, with a flower pot or soda can sitting on top full of thermite. They then light this with a strip of magnesium and a torch. I wanted to do something a little different. I wanted to implement thermite as a self destruct mechanism inside the device. To do this, I had to come up with a way to ignite the thermite. This stuff is very difficult to light. You have to get it really really hot. The easiest way is to use magnesium, which itself isn’t the easiest thing to light. What I finally landed on was an ignition system that uses model rocket igniters, gun powder, and magnesium to light the thermite.  The model rocket igniter can be set off from the 12v line inside your computer. However, it isn’t hot enough to light magnesium shavings, much less thermite. To get it to work, I needed to add some gunpowder. A small amount of gun powder would get hot enough to light the magnesium shavings, which in turn were hot enough to light the thermite. I had to be careful though, because too much gunpowder would cause a rapid expansion, blowing the thermite everywhere instead of lighting it. You can actually see some red thermite being blown out of the external hard drive and the laptop as the gunpowder ignites. Effectiveness of external hard drive self destruction: I wasn’t sure about this one. There isn’t a whole lot of space for thermite and the ignition system inside the box. On top of that, the only space was at the side of the hard drive, where the walls are the thickest. I had no idea if the small amount of thermite I used would penetrate the drive. It did, just barely as you can see in these pictures. It looks as if it pooled in the screw holes  and made it inside. The platters are damaged. Effectiveness of laptop destruction: I decided to completely replace the cd rom with thermite. This gave me a ton of space to put things. I was pretty positive this would work. The hard drive is in the center of this laptop, which meant I had to place it on its side for this to be effective. You can see the thermite work its way down toward the drive in the video. As you can see in the pictures below, the drive cover is completely gone and the platters are destroyed. Success! Since this system can be powered by batteries or the internal power of your computer, it can be put inside a working device only to be used when needed. Obviously it is a ridiculous fire hazard that no one should bother with. It was a fun experiment though and I really feel like it is something that would fit in well in the world of [James Bond] Filed under: chemistry hacks, computer hacks, Featured

Check out this BeagleBone Black update of the 3D printing-friendly Replicape Beagle Bone cape project from Hipster Circuits: There it is, the new revision of Replicape. This revision is more compatible with the new BeagleBone Black that has a built in eMMC. There are a lot of other changes as well on this revision. The most important is the moving of the stepper motor  connectors to the outside of the receptacles so removing is no longer necessary. Furthermore there is no need for a separate 12V and 5V power supply. You can now power the whole board with a single 12 to 24V PSU. Other things to mention is a major upgrade to the tracks and connectors for the heater cartridges and heated build platform, the addition of a fuse and finally a new color so that there will be no doubt which BeagleBone this belongs to : ) I’ve gotten a lot of help from Dirk Eichel on this revision, especially on the fat power tracks, the addition of a freewheeling diode across the MOSFETs to suppress voltage spikes and grips to reduce noise on the ADC lines. Although there are a lot of nice changes, there has also been a lot of work put into keeping the cost down. The total cost of the board is the the same (BOM is ~$90). I’ll give it a couple of days to get input from the community both on bugs in the layout/schematic and feature requests. Have a look at the RevA2 tag of the repository. Read more. Every Thursday is #3dthursday here at Adafruit! The DIY 3D printing community has passion and dedication for making solid objects from digital models. Recently, we have noticed electronics projects integrated with 3D printed enclosures, brackets, and sculptures, so each Thursday we celebrate and highlight these bold pioneers! Have you considered building a 3D project around an Arduino or other microcontroller? How about printing a bracket to mount your Raspberry Pi to the back of your HD monitor? And don’t forget the countless LED projects that are possible when you are modeling your projects in 3D! The Adafruit Learning System has dozens of great tools to get you well on your way to creating incredible works of engineering, interactive art, and design with your 3D printer! If you’ve made a cool project that combines 3D printing and electronics, be sure to let us know, and we’ll feature it here!

The ultimate simple DIY with LEDs — kazuhiro yamanaka created this sweet and simple rolled paper LED flashlight. via designboom. The paper serves as both the encasement for the battery-powered LED and the source of illumination. The torchlight unrolled. Planning illustration from Yamanaka.

Most project tips involving brainwaves get passed over because it’s hard to make much out of that type of control. This project doesn’t necessarily make progress on the control side on this, but you have to admit that herding life forms with your thoughts deserves a closer look. [Geva] set up a rig that allows him to interact with paramecium — tiny single cell organism that are happy to swim around all day long. Just like vertebrates they’re not big fans of electric shocks. Run some current through the fluid and they’ll swim toward the negative electrode. This experiment uses four pencil leads as electrodes. These are driven by an Arduino which reacts to the input from a toy brain wave device. Concentrate in just the right way and they will swim wherever you will them to. This isn’t quite as involved as cockroach mind control, but it’s every bit as interesting Filed under: Medical hacks

Here’s short review from SolidSmack.com addressing the recent crowdfunding project 3D Printer Test Kit by 3DKitbash.com — a set of tools designed to help you calibrate and analyze the calibration of your desktop or professional 3D printers: As the number of 3D printers purchased each week increases exponentially, many proud new owners of a 3D printer are also learning the limitations of their new device. Chances are, an entire weekend may have been spent calibrating your printer or waiting for that very first test print. But what about the other limitations of your material? Recently posted on Kickstarter, the 3D Printer Test kit offers eight unique sample chip files that allows a user to test everything from ridges to flexibility to overhangs so you’ll know exactly where the limitations and strengths are for your 3D printer…whether it’s a Replicator 2 or a Fortus. FOR PROS AND CONSUMERS With the rise of consumer-level personal manufacturing, there will oftentimes be a disconnect between the understanding of material properties and expectations for a final product. As professional toy developers, the designers at 3DKitBash have no doubt done their homework and deciphered an affordable and accurate method for teaching both professionals and consumers how far they can stretch their 3D prints. We want to help Makers, Inventors, and 3D Explorers do their thing Better & Faster. It’s a passion of ours and one that keeps us constantly on the move. -3DKitBash The kit consists of 8 ‘Tolerance Chips’ that each highlight a unique material characteristic to see how your 3D printer performs with various shapes and forms. While your 3D printer and material may excel in one characteristic, it may not do so hot in another, which can ultimately save you a lot of time and money down the road. And here are the tests: Read more.

[This post is originally from my blog. I'm bringing this spectrum analyzer to Darren Kitchen's Hak5 event at OMSI this Saturday (2013/05/25).] Here's some details of my radio spectrum analyzer hack at Maker Faire. But first, a quick video of the hack in action: src="http://www.youtube.com/embed/rmVu_mw3aJU" width="640"> Technical Details This project is built around the HackRF, a software-defined radio transciever. I programmed it to sample 20MHz of radio spectrum from an antenna, do a frequency analysis on the data, and display the results on a Noritake vacuum fluorescent display. I added the tuning wheel mid-afternoon on Sunday, and it really improved the interactivity of the display. It felt really cool to spin the wheel around and watch the spectrum scroll back and forth. Too bad I didn't capture that in the video... href="http://www.sharebrained.com/wp-content/2013/05/radio-spectrum-analyzer1-e1369184474197.jpg"> alt="" class="aligncenter size-medium wp-image-1009" height="560" src="http://www.sharebrained.com/wp-content/2013/05/radio-spectrum-analyzer1-e1369184474197-420x560.jpg" title="Radio Spectrum Analyzer at Maker Faire 2013" width="420"> The HackRF's microcontroller is an ARM Cortex-M4F + Cortex-M0 "dual core" chip. Both are running at 204MHz. The M4F has hardware floating point, which drastically simplifies the signal processing code. The ARM grabs 512 complex samples at a time from the radio analog-to-digital converter (ADC). It applies a href="http://en.wikipedia.org/wiki/Window_function">window function that reduces artifacts from sampling arbitrary chunks of a radio signal. The windowed samples are converted to href="http://en.wikipedia.org/wiki/Frequency_domain">frequency domain data through a 512-point href="http://en.wikipedia.org/wiki/Fft">fast-Fourier transform (FFT). The frequency data that comes out of the FFT (frequency vs. a complex vector) is converted to real magnitudes. I take the logarithm of each magnitude to get values vs. frequency that resemble href="http://en.wikipedia.org/wiki/Decibel">decibels. Then, I scale the log-magnitude data to fit nicely on the vacuum fluorescent display, which is 384 x 32 pixels. For each frequency in the scaled data, I render a bar into a frame buffer I maintain in RAM, using cute bit-shifting tricks. Then, I render marks at 1MHz intervals to provide a tick-mark scale on the display. In the left corner of the display, I render minimum and maximum sample buffer values for each of the two sampling channels -- this is so I can tell if I need to turn up or down the gain on the receiver. I draw the current tuning frequency in MHz at the center of the display. Lastly, I scan out each of the pixels, one byte at a time, into the VFD's parallel 8-bit interface, using the display's "Graphic DMA" mode. The optical href="http://en.wikipedia.org/wiki/Rotary_encoder#Single-track_Gray_encoding">quadrature encoder runs purely on interrupts. Whenever a positive- or negative-going edge is detected on either of the two optical sensors, an interrupt is generated. Based on the current and previous values of the optical sensors, the software (borrowed from PJRC's Encoder Library) decides if the wheel has moved, and if so, which way it has moved. Based on that decision, the tuning frequency is incremented or decremented. There was a hairy bit of wiring between the HackRF and the VFD. I needed to interface the HackRF, which is a 3.3 Volt device, to the VFD, which communicates at 5 Volts. So I needed to translate several signals between those two voltages. I had an old circuit board from my Robotron-FPGA project that did exactly that, for a completely different purpose. But with enough wires and headers and disgusting rewiring, I made it work. But it wasn't pretty. I had to keep poking it and twisting it, as some signals were intermittent and sometimes needed my help. The Faire Experience The HackRF can tune from below 10MHz (where it

Check out Greg Petchkovsky’s fascinating “real world mashups” shared in his Instructables project “A sandstone block built from lego, blending real objects with 3d prints“: By combining 3d scanning, 3d digital modeling, and 3d printing, it is possible to create amazing and surprising effects, objects that can seamlessly blend between reality and imagination. In this tutorial, I describe the process of making a full colour 3d printed object that seamlessly fits on to a real sandstone wall, producing the illusion that the wall is built from pieces of lego. But the techniques described  have a more general usefulness, almost limitless potential, and  are easier and less expensive than you might think! Staring with a real physical object, in this case a sandstone brick wall, I create an inexpensive but high quality digital 3d scan using a stills camera and the program Agisoft Photoscan. I then model the lego brick shapes over this scan using 3d software, I make this model fit perfectly onto the scanned wall by using boolean subtraction, I add colours clone stamped from the photos, correct the scale, and finally I do a colour 3d print, which fits seamlessly onto the sandstone wall, producing a novel illusion that would be difficult to achieve by other methods…. Read more.