GSM Controlled Car Without Needing A Microcontroller

July 12, 2012 by Mike Szczys 8 Comments

Nope, no microcontroller here, just a full-blown cellphone used as the brains of this little robot. The secret behind how it works is in the sounds the phone makes. The touch tones, known as DTMF, are monitored by the circuit mounted on the front half of the chassis and are responsible for driving the motors.

[Achu Wilson] built the circuit around an MT8870 chip which decodes the DTMF sounds and uses the BCD output to feed some logic chips. A 4 line to 16 line decoder and an inverter chip format the signals for use as inputs to the L293D motor driver. The video after the break shows him driving the rover directly by pressing number on the phone (like a tethered remote control). But he mentions that it’s possible to call the phone and press the numbers remotely. We assume you need to connect the call manually as we see no way to automatically answer calls.

This is certainly a fun way to play around with the DTMF protocol.

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Digital Picture Frame That Rotates To Match Image Orientation

July 12, 2012 by Mike Szczys 7 Comments

This digital picture frame physically rotates in order to match the image’s orientation. [Markus Gritsch] built the frame, including a Python script to translate the photos to a format which makes the best use of the 2.4″ LCD screen.

The screen is addressed in 8-bit parallel by a PIC 32MX120F032B processor. Image are read from an SD card in a raw format, with 16-bit colors pushed to the display for each pixel. To get them into this format [Markus’] script converts the JPEG files to RAW, resizes them, uses dithering to reduce to 16-bit color, then applies a sharpening filter to improve the final look. During this process it also includes orientation information. That is parsed by the microcontroller and used to drive the servo motor to which the screen is attached.

To finish off the project he spray painted a piece of acrylic to act as a bezel for the frame. Check out the demo after the break and we think you’ll agree the rotating feature, along with image scrolling, really makes this a piece you’ll want on your own desk.

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Flying Batman Is A Load Of Bull

July 12, 2012 by Mike Szczys 36 Comments

Batman’s ability to fly is a falsehood. Or at least so says science. We didn’t know science was into disproving super-hero movies (that’s a deep well to drink from) but to each his own. But back in December the Journal of Physics Special Topics took on the subject with their scholarly paper entitled Trajectory of a Falling Batman. The equations presented in the two-page white paper may be above your head, but the concepts are not.

It’s not that Batman can’t fly in the way explained in the film. It’s that he can’t land without great bodily harm. By analyzing the cape in this frame of the film, researchers used Batman’s body height to establish wing span and area. The numbers aren’t good. Top speed will reach about 110 km/h with a sustained velocity of 80 km/h. That’s 80 mph at top speed and just under 50 mph when he comes in for a landing.

Oh Batman, how you’ve let us all down. If you liked this paper, you should dig through the archives. We always wondered if [Bruce Willis] could have actually saved the world from an asteroid.

[via Dvice]

[Todd] Literally Debugs This Printing Calculator

July 12, 2012 by Mike Szczys 13 Comments

This printing calculator is a thrift store find. [Todd Harrison] picked it up for a measly $3, and it still works! But the device is about twenty years old and he thinks it’s time to clean up the aging hardware.

After cracking open the case he digs out some of the stuff that has made its way inside. This includes a few dried up moths (debugging complete). While everything is open he gives a tour of the components. The calculator has a VFD which is definitely worth the price tag of the unit even if you just want to reuse the display in another project. But that’s not all. The printing head would be a fun thing to play with as well. We could see using this in projects similar to some of the thermal printer hacks we’ve seen.

When put back together, and given a new ink ribbon, the unit is ready for another 10-years of holding down one corner of your desk. Don’t miss [Todd’s] tear-down and clean-up video after the break.

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Reading Bar Codes With Arduino And Unaltered CueCat

July 12, 2012 by Mike Szczys 11 Comments

[Damcave] decided to try out some bar code reader projects. He got his hands on a CueCat years ago. The problem is that it outputs encrypted character sets instead of a clear text string. To get around this he used his Arduino to decrypt the CueCat’s data output.

Originally you could get you hands on a CueCat for free. It was meant to work like QR codes do now — you see a bar code, you scan it to get to a web address. It never really took off but you can still get your hands on one for about twelve clams. We’ve seen projects that clip a pin on the processor to disable to encryption. But [Damcave] didn’t want to mess with the hardware. Instead he connected the Arduino via the PS/2 connector and used software to translate the data. The encryption format has long been know so it was just a matter of translating the steps into an Arduino function.

Energia Brings Arduino IDE To The TI Launchpad

July 12, 2012 by Mike Szczys 40 Comments

The Arduino IDE is an abstraction layer for the AVR chip which the board is based around. So it’s no surprise that it is now possible to use the Arduino IDE with the TI Launchpad board. This makes it dead simple for beginners to play around with the inexpensive and low-power MSP430 platform. This is all thanks to a lot of hard work on part of the Energia developers.

The project branches from Arduino so the look, feel, and function are all about the same. Most notably, the color scheme has migrated to red to match the board color of the Launchpad. You can configure the hardware the same way by selecting a COM port and target board. Almost everything is already working, but you should check the known issues page so that you don’t try to use a function that hasn’t been ported. Right now the list includes the random and random seed functions, as well as tone, notone, and micros. There is also an issue with analogWrite; it will only produce half the requested frequency and duty cycle can only be set from 0-50%. Still this is a great development if you’re most comfortable working from this IDE.

Nyan Fax Brings The Celebrity Kitty To Your Office

July 11, 2012 by Mike Szczys 20 Comments

Internet blocked at your office and feel like you’re just not getting your fix of Nyan Cat? Don’t worry, you can now use the fax machine to get your fix. [Tom Scott] put together the project to our delight, which will work best if you can find one of those fax machines that uses the continuous roll of paper. But as you can see above, individual sheets will work too. The best part is that Nyan Fax is live for callers from the UK and internationally!

The hack is using something called ‘fax polling’. It allows the sender to set up an on-demand server where any caller will be sent a queue of documents. In this case [Tom] crafted a Nyan Cat document that never ends… you’ll need to disconnect the phone line or pull the pug to stop the printing. See for yourself in the clip after the break. If you’re interested in setting up your own it can be done with the mgetty and sendfax packages on a Linux box.

Just in case you’re keeping score, [Tom Scott] is one of the guys behind the Webcycle.

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