The LVL1 Hackerspace held a hackathon back in June and this is one of the projects that was created in that 24-hour period. It’s a 3D scanner made from leftover parts. The image gives you an idea of the math used in the image processing. It shows the angular relations between the laser diode, the subject being scanned, and the webcam doing the scanning.
The webcam is of rather low quality and one way to quickly improve the output would be to replace it with a better one. But because the rules said they had to use only materials from the parts bin it worked out just fine. The other issue that came into play was the there were no LCD monitors available for use in the project. Because of that they decided to make the device controllable over the network. On the right you can see a power supply taped to the top of a car computer. It connects to the laser (pulled out of a barcode scanner which produces a line of red light) and the turntable. A Python script does all of the image processing, assembling each slice of the scan into both an animated GIF and an OBJ file.
[Jack Crossfire] took one of those inexpensive indoor helicopters and made it autonomous. He didn’t replace the hardware used for the helicopter, but augmented it and patched into the remote control to make a base station.
The position feedback is provided in much the same way that the Wii remote is used as a pointing device. On the gaming console there is a bar that goes under the TV with two IR LEDs in it. This is monitored by an IR camera in the Wii remote and used to calculate where you’re pointing the thing. [Jack’s] auto-pilot system uses two Logitech webcams with IR filters over the sensors. You can see them mounted on the horizontal bar in the cutout above. The helicopter itself has an IR LED added to it that is always on. The base station follows this beacon by moving the cameras with a pair of servo motors, calculating position and using it when sending commands to the remote control’s PCB.
Don’t miss the demo video of the rig after the break.
Continue reading “Autonomous helicopter works like a Wii remote”
The folks at the London-based startup GoCardless have a pool table at their office. Being the techies they are, they decided to build a system that automatically scores games. The results, while not fully complete, are still pretty impressive for something whipped up during a 48 hour hackathon.
The automated score keeper uses a webcam duct taped to the ceiling right above the center of the pool table, The balls – red and yellow balls replace the rainbow of solids and stripes to make things easier – are found using OpenCV.
This build isn’t quite finished yet. The people at GoCardless are looking to improve the accuracy of their setup by using a camera with a higher frame rate and possibly moving on to physics simulation to predict where the balls should be. If these guys get the time, they could add something like augmented reality pool table to improve shot accuracy.
Vidia after the break.
Continue reading “Computer tracking of billiard balls”
Hackaday reader [Tom Price] often uses Skype to communicate with family near and far, but he was getting tired of adjusting his webcam each time his kids moved out of frame. While the solution he came up with isn’t fully automated, it is hands-free, which is good enough for his purposes.
[Tom] was looking around for an electronic foot pedal of some sort when he came across a wireless 3rd party Guitar Hero peripheral that happened to fit the bill. Using an Arduino library created by [Bill Porter], he was quickly able to get the toy to communicate with an Arduino-flashed Atmega8, but things kind of fell flat when it came time to relay signals back to his computer. Using another Atmega8 along with the PS2X library, he was able to emulate the Guitar Hero controller that his foot pedal was looking for.
With the pedal portion of his project wrapped up, he focused on his webcam. [Tom] mounted the camera on a small servo, which he then wired up to the receiving end of his foot pedal rig. As you can see in the video below, he can now pan his camera across the room with a tap of his foot, rather than leaning in and manually adjusting it.
Continue reading “Controlling your webcam with an old Guitar Hero pedal”
[Jeremy Blum] wrote in to share his LibeTech QR Code Door Lock project. He developed it during his Senior year at Cornell University along with three of his classmates. It seeks to move away from magnetic card locks in favor of optical locks that authenticate based on a QR code.
The hardware he’s using here is definitely cost prohibitive, but we’re sure the concept could be greatly simplified. In this case a BeagleBone running embedded Linux monitors a feed from a webcam. When it detects a QR code it compares it with a database of approved keys and will unlock the door for you.
There are problems with this technique, one being that an attacker might be able to get a usable photograph of your key without you knowing. But the majority of hotel locks in use right now are even less secure than that. On the upside, the key to your room can be emailed to you for use on just about any device with a screen, or printed out on a piece of paper.
You can find [Jeremy’s] presentation video embedded after the break.
Continue reading “QR code opens doors to you”
The guys over at Section9 Hackerspace in Springfield, Missouri just finished building this treaded robot. Despite the juxtaposition of the cat, it really doesn’t defend anything. The project is a reconnaissance robot controlled over the network with video feedback.
The team started off with some lofty goals. They wanted to the robot to be able to climb stairs and to feature a detachable flying portion in order to get a better look at hard to reach places. Cost and complexity are cited as the reasons they ditched the idea of the flyer. The rest of the features came out much as planned. The motor controller for the treads is connected to an Arduino. This uses an Ethernet shield to connect to the WRT54G router which is also coming along for the ride. This seems a bit over-powered but it makes it easy to connect the webcam on the front (also via Ethernet).
On the software side they wrote an Android app. It controls the movement of the robot, as well as that of the camera. Of course you need to see where you’re going so they went the extra mile to include video from the webcam. Check out their show-and-tell video after the break.
Continue reading “Tank router defends your pets?”
If you want to find out what something is made out of, you’ll probably be using a spectrometer. These devices allow scientists to determine what something is made of by shining light through an object and recording what colors are absorbed. Professional spectrometers cost many thousands of dollars, but you can build your own using a simple USB web cam, an old DVD-R, and a VHS cassette case.
In this tutorial of Public Labs’ DIY video spectrometer, [Jeffery] takes us through the process of building a spectrometer. After cutting a small bit of plastic from a DVD-R and mounting it on the lens of a web cam, [Jeff] puts the webcam in a VHS case and shines a light through a small slit. The result is a rainbow pattern captured by the webcam, and by putting different translucent materials in front of the light source, the spectrum slightly changes.
Of course a DIY spectrometer is nearly useless without a library of materials and their associated spectra. [Jeffery] is working on this as well with a wiki-style app called Spectral Workbench.
There’s a video tutorial for making your own DIY spectrometer available after the break. It seems like an easy build, if you can find the requisite VHS cassette case in your basement and/or attic.
Continue reading “Turning a webcam into a spectrometer”