LiPo Powered Stellaris Launchpad

October 16, 2012 by 20 Comments

Want mobile power for your Stellaris Launchpad development board? [Philipp] was looking to add some lithium power for the Launchpad. He used an off the shelf single cell LiPo battery and connected it to the 5V rail of the Launchpad board. It didn’t work.

So [Philipp] started looking through the schematics and noticed that the regulator was working fine, but the Stellaris wasn’t starting up. He tracked down a voltage supervisor connected to the Stellaris reset pin. After some investigation, it was clear that this supervisor was holding the device in reset.

The solution is a quick and dirty hack: cut the trace that connects the reset line to the voltage line. With this modification, the device starts up from the LiPo without any issues. [Philipp] does note that you should be careful about battery under-voltage and over-voltage. This hack doesn’t handle charging the LiPo battery, but we’ve discussed that in the past.

Magic Finger Input Device Is A Camera On Your Finger Tip

October 16, 2012 by 35 Comments

What if we could do away with mice and just wear a thimble as a control interface? That’s the concept behind Magic Finger. It adds as movement tracking sensor and RGB camera to your fingertip.

Touch screens are great, but what if you want to use any surface as an input? Then you grab the simplest of today’s standard inputs: a computer mouse. But take that one step further and think of the possibilities of using the mouse as a graphic input device in addition to a positional sensor. This concept allows Magic Finger to distinguish between many different materials. It knows the difference between your desk and a piece of paper. Furthermore, it opens the door to data transfer through a code scheme they call a micro matrix. It’s like a super small QR code which is read by the camera in the device.

The concept video found after the break shows off a lot of cool tricks used by the device. Our favorite is the tablet PC controlled by moving your finger on the back side of the device, instead of interrupting your line of sight and leaving fingerprints by touching the screen.

Continue reading “Magic Finger Input Device Is A Camera On Your Finger Tip” →

Face Tracking With An Android Device

October 15, 2012 by 7 Comments

This Android device can recognize faces and move to keep them in frame. It’s a proof of concept that uses commonly available parts and software packages.

The original motivation for the project was [Dan O’s] inclination to give the OpenCV software a try. OpenCV is an Open Source Computer Vision package that takes on the brunt of the job when it comes to discerning meaning from images. To give the phone the power to move he designed and printed his own mounting brackets for the phone and a couple of hobby servos. An IOIO board connects to the Android device in order to control the motors. On the software side all [Dan] needed to do was write some code to interface the output of the OpenCV face tracking modules with the input of the IOIO. See the finished project demonstration after the jump.

This system can easily be implemented with other hardware, like this Arduino-based version we looked at earlier in the year.

Continue reading “Face Tracking With An Android Device” →

Mirage 2.0 Lights Up The Desert With 4,024 LEDs

October 15, 2012 by 17 Comments

Registering a mutant vehicle at the Burning Man Department of Mutant Vehicles (DMV) is rough. To be allowed to operate at night, wacky rolling creations have to have a certain degree of lighting presence. This keeps vehicles  from blending into the scenery. Unfortunately Mirage 1.0 was built specifically with this in mind,  using reflective surfaces to turn a van into a semi-invisible shiny slab. Not even EL wire, an illuminated dance floor, and spot lights could placate the DMV. The solution? Wrap the entire friggen vehicle in a netting of 4,000 LEDs! Take that officials!

Most of the hardware is Phillips display stuff, digital LED fixture controllers are used to interpret HDMI data and then pipe out color data to addressed chains. All this mapping and addressing means that the entire setup functions like a 168×24 pixel monitor.  Split chains of LEDs also happen to allow the crew to operate the doors and get in and out of the vehicle.

The underlying car was built on the same sort of principal that hid the wheels of  Skywalker’s landspeeder, only in this case the idea was to cover an entire car with mylar and mirror. An interesting side effect of this mirror wrapping is that a sheen of desert dust helps reflect the ambient LED light quite well, blurring pixel colors together. It sort of makes us wonder about picking up a bucket of Mylar for some of our spaced out displays.

The Mirage crew has plans for next year, and have videos of several ideas on the site (portions of the test videos are NSFW).  Check out the video of Mirage 2.0 in action after the jump! Thanks [erland]!

Continue reading “Mirage 2.0 Lights Up The Desert With 4,024 LEDs” →

Arduino Parking Lot Attendant

October 15, 2012 by 25 Comments

Here’s an automatic parking gate for toy cars. There’s no need to press a button, the electronics detect the presence of a vehicle on either side of the gate, raising it after verifying that the lot is not already full. It’s the same idea as counting how many people enter a room in order to switch the lights but the hardware is just a bit different.

The system is controlled by a pair of sensors in the paper which serves as the parking lot. There are three sheets of heavy stock, the top and bottom both have aluminum foil on them, with the center layer  as a separator. There are holes cut in the separator where the hash marks are seen above. By adding a little pressure to the car when you drive it up to the gate this completes a circuit instructing the Arduino that there’s a vehicle in position.

You can see a demonstration, as well as the guts of the build, in two videos after the break.

Continue reading “Arduino Parking Lot Attendant” →

Singing Pumpkins

October 15, 2012 by 6 Comments

This Halloween table will sing a sweet serenade to spook your guests. Each of the animatronic pumpkins were quite easy to build, but you may end up spending a bit more time choreographing the performance.

Inside each Jack-o-lantern you’ll find a custom Arduino compatible board called a Minion board. These include a wireless connection which lets the system sync with the computer playing the audio. The pumpkins are fake, which means that can be reused year after year (unlike our LED matrix inside a real pumpkin). The mouth is connected to a servo with a short piece of bent wire, allowing it to flap along with the words of a song. You can see a performance of the Ghostbusters theme in the clip after the break.

A custom GUI was written in C# to aid in the choreography. It handles the playback of the song, with a few buttons that can be used to record the light and mouth effects. This ‘recording’ is then used to drive the pumpkins during a performance.

Continue reading “Singing Pumpkins” →

Repairing A Junked Signal Generator

October 15, 2012 by 21 Comments

We must be walking past the wrong dumpsters because we certainly haven’t encountered equipment like this just waiting to be salvaged. [Shahriar] found an HP 8648C Synthesized Signal Generator while he was ‘dumpster diving’ and set out to fix the malfunctioning lab equipment. He posted a 1-hour video on the project, which you can find embedded after the break. The actual fix happens in the first half, the rest of the video is spent testing the resurrected device.

The back corner of the case has been dented, which may be the reason this has been thrown out. When it is first powered it emits an unpleasant screeching noise and the user interface doesn’t do anything. [Shahriar] says he recognizes the sound as a malfunctioning switch-mode power supply. Sure enough, when disconnected from the main board it still makes the noise. It turns out there’s a huge electrolytic capacitor the size of a stack of poker chips which has come loose from the PSU board. When it’s resoldered the device fires up as expected.

Now how are we going to find a digital capture oscilloscope that just needs to have its PSU reassembled?

Continue reading “Repairing A Junked Signal Generator” →