It seems like holiday decorations come up earlier and earlier every year. You might not have room for a full-blown tree in your lab, but if you have an arbitrary waveform generator and a scope, Tektronix has a way for you to show your spirit electronically.
You can see the video below. Naturally, it features Tektronix gear, but we are pretty sure you could make it work with any arbitrary waveform generator that has at least two channels and a scope with an XY mode.
Continue reading “A Christmas Tree for your Lab”
Here’s a camera rig that makes it a snap to produce photorealistic 3D models of an object. It was put together rather inexpensively by an indie game company called Skull Theatre. They published a couple of posts which show off how the rig was built and how it’s used to capture the models.
They’re using 123D, a software suite which is quite popular for digitizing items. The rig has a center table where an object is placed, and a movable jig which holds three different cameras (or one camera for three rotations). You can see the masking tape on the floor which marks the location for each shot. These positions are mapped out in the software so that it has an easy time putting them all together. The shaft which connects the jig to the base is adjustable to accommodate large or small items.
One thing that we found interesting is the team’s technique for dealing with reflections. They use a matte spray to make those surfaces less reflective. This helps 123D do its job but also allows them to map reflective surface more accurately using the game engine.
This turntable can automatically digitize objects for use in 3D rendering software like Blender3D. [James Dalby] built it using a high-quality DSLR, and some bits and pieces out of his junk box. The turntable itself is a Lazy Susan turned on its head. The base for the spinning model is normally what sits on the table, but this way it gives him an area to rest the model, and the larger portion acts as a mounting surface for the drive mechanism.
He used the stepper motor from a scanner, as well as the belt and tension hardware from a printer to motorize the platform. This is driven by a transistor array (a ULN2003 chip) connected to an Arduino. The microcontroller also controls the shutter of the camera. We’ve included his code after the break; you’ll find his demo video embedded there as well.
The concept is the same as other turntable builds we’ve seen, But [James] takes the post-processing one step further. Rather than just make a rotating gif he is using Autodesk 123D to create a digital model from the set of images.
Continue reading “Scanning turntable digitizes objects as 3D models”
Elaborating on an item previously mentioned among last weekend’s Cornell final projects list, this time with video:
For their ECE final project, [Adam Papamarcos] and [Kerran Flanagan] implemented a real-time video object tracking system centered around an ATmega644 8-bit microcontroller. Their board ingests an NTSC video camera feed, samples frames at a coarse 39×60 pixel resolution (sufficient for simple games), processes the input to recognize objects and then drives a TV output using the OSD display chip from a video camera (this chip also recognizes the horizontal and vertical sync pulses from the input video signal, which the CPU uses to synchronize the digitizing step). Pretty amazing work all around.
Sometimes clever projects online are scant on information…but as this is their final grade, they’ve left no detail to speculation. Along with a great explanation of the system and its specific challenges, there’s complete source code, schematics, a parts list, the whole nine yards. Come on, guys! You’re making the rest of us look bad… Videos after the break…
Continue reading “Human Tetris: object tracking on an 8-bit microcontroller”
This method of book digitization allows you to scan an entire book by fanning through the pages. It uses a high-speed camera that captures 500 frames per second to get a good look at each page. Processing software isolates each pages, analyzes any curve in the paper due to the flipping, and smooths out the image for better optical character recognition results. The greatly reduces the time it takes to digitize a book, even compared to setups that automatically flip pages.
For those of you who have been dreading the day that you have to dig out those old family films in Super 8 format and take them to get digitized, dread no more. Now you could turn it into a cool project. [Photobsen] has posted pictures of an automated system for scanning and compiling the film into a digital movie. There was already software available, called CineToVid, which would take the scanned segments and create a video from them, but doing the actual scanning was quite laborious. [Photobsen] built a quick automated system using an old floppy drive connected to his computer via parallel port. He now scans about 80 seconds of film per hour, unattended.
Google has acquired reCAPTCHA and plans to use the system for digitizing books. Wait… what? CAPTCHA is the method of requiring a user to type in a visually obscured word to prove they are human. How can this digitize books? The answer is a bit obscure and takes some time to discover, but you’ll have fun along the way. Continue reading “Are you human? Then type out this book”