arduino

2925 Articles

Automatic Airplane Tracking; What Radar-systems Engineers Do For Kicks

May 4, 2012 by 15 Comments

[G. Eric Rogers] is a radar-systems engineer who just happens to live within sight of the aircraft approach path for the local airport. We wonder if that was one of the criteria when looking for a home? Naturally, he wanted his own home-based system for tracking the airplanes. He ended up repurposing a motorized telescope for this purpose.

The system does not actually use Radar for tracking. Instead, the camera strapped to the telescope is feeding a video experimenter shield. A tracking algorithm analyzes the video and extrapolates vector data. From there, the base unit can be controlled by the Arduino via an RS232 interface.

There are some bugs in the system right now. The Arduino has something of an ADHD problem, losing interesting and going to sleep in the middle of the tracking process. [Eric’s] workaround uses the RS232 board to periodically reset the Arduino, but he hopes to squash this bug soon.

Reaching Out To A Touch Screen With A Microcontroller

May 4, 2012 by 20 Comments

We love capacitive touch screens. They’re much more robust than resistive touch screens and if the UI is programmed well they produce a great user experience. But getting your electronics project to interact with one is a bit tough. [RobB] has been experimenting in that area, and managed to build a simple touchscreen actuator for microcontroller use.

In the video after the break you can see his proof of concept. He’s using an Arduino to enter the number 2 on an Android  iOS calculator app once every second. It doesn’t take much to pull off this trick, [RopB] just taped a piece of tin foil to the screen and connected it to the Arduino with a jumper wire. The pin is left floating until a screen tap is needed, at which point it is pulled to ground.

A custom app operating at slow speeds could use this as an input technique. Two pieces of foil (one acting as clock, the other data) would provide a rudimentary serial transfer system.

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Arduino PIC Programmer Writes To 18F Family

May 4, 2012 by 10 Comments

[Kirill] wrote in to share his Arduino-based PIC programmer. It is capable of writing to the 18F family of chips, including 18F2XXX and 18F4XXX. We think that’s pretty exciting because this line of chips has USB functionality and there are bootloaders out there that let you program them via USB. So if you wanted to build your own PIC dev-board (like this one) you can use your Arduino to flash the bootloader.

This post comes hot on the heels of the Arduino being used as a PIC 16F programmer. That hack has a rudimentary programming GUI, something that [Kirill] admits his lacks but has no plans to implement himself. Perhaps someone will do a little porting work to merge the projects, adding to the range of chips supported by this programming technique.

Turning A Light Off Over The Internet

May 3, 2012 by 23 Comments

Because reaching over a few feet to turn off a switch is too much to bear for [Bruce], he connected his desk lamp to the Internet. It’s a pretty cool build that’s the perfect tutorial for connecting just about anything to the internet.

For his build, [Bruce] used an Arduino with a relay attached to an output pin. When the Arduino receives a signal on its serial port, a tiny voltage is applied to the relay, turning on the light.

This could have been done with an Arduino Ethernet, but the PHP script [Bruce] went with is a little more versatile. Whenever someone pulls up this digital light switch web page, they can turn [Bruce]’s desk lamp on and off.

For an introduction to connecting bare bones projects to the Internet, we’re really liking [Bruce]’s build. Just try no to go crazy with that link and leave the failure testing to the professionals. You can check out the demo video after the break.

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Arduino Can Program PIC Too!

May 2, 2012 by 22 Comments

This is a wiring diagram that [Soranne] put together when developing a method of programming PIC microcontrollers using an Arduino board. You can see that he takes care of the 12V issue by connecting the Master Clear (MCLR) pin to an external source. This comes with one warning that the Arduino should always be reset just before making that connection.

He’s tested this with a 16F628 and is happy to report that he can successfully flash the program memory, but hasn’t implemented a way to write to the EEPROM as of yet. This should work for any of the 16F family of chips, but we’d bet this will be extended if some knowledgeable folks decide to lend a hand.

On the PC side of things [Soraane] has been working on a program to push code to the Arduino via the USB connection. He’s developing it in C# and even has a GUI worked up for the project. You can get your hands on the software in the second post of the thread linked above but you’ll have to be logged into the Arduino forum to see the download link.

We think the 12V issue is why we don’t see more roll-your-own programmers for PIC. But there are a few solutions out there like this ATmega8 version.

Sun-powered Stirling Engine With Automatic Tracking

May 2, 2012 by 32 Comments

Check out this solar-powered Stirling engine (translated). The build is part of a high school class and they packed in some really nice features. The first is the parabolic mirror which focuses the sun’s rays on the chamber of the engine. The heat is what makes it go, and the video after the breaks shows it doing just that.

But the concept behind the mirror makes for an interesting challenge. The light energy is focused at a narrow point. When the sun moves in the sky that point will no longer be at an efficient position to power the engine. This issue is solved by a pair of stepper motors which can reposition the dish. It’s done automatically by an Arduino Uno which makes readings from four LDR (photoresistors) in that cardboard tube mounted at the top of the dish. If the light intensity is the same for all four, then the tube is pointed at the sun. If not, the motors are tweaked to get the best angle possible.

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Surround Sound System Controller Replacement Includes Home Automation

May 2, 2012 by 3 Comments

[Neoxy] always wanted surround sound for his computer, and one day he managed to get a hold of a dead 5.1 system. Why buy one when you can repair someone’s rubbish, right? That turned out to be easier said than done, but after several false-starts he managed to resurrect the audio system by replacing the microcontroller.

We find his trouble-shooting technique interesting. The amp would power up without a hitch but no sound would come out of it. So he took a headphone cable and used the L and R conductors as probes. That cable was fed from an MP3 player, and by touching the probes to the audio inputs for the pre-amp and amplifier circuits he could get great sound out of the speakers. Reasonably certain that those boards were working fine he narrowed down the troubles to three chips that mix, select inputs, and control the system.

A lot of prototyping with an ATmega328 and an Arduino led him to the functionality you see in the video after the break. Not only did he get the system working, but he’s using the Arduino to add Internet control for the device.

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