This DIY Metal Hunting Robot uses some Parallax processing to hunt down metal objects while avoiding bumping into items in the way.

“To avoid any collision with other objects (such as furniture), the robot uses an ultrasonic range detector (radar) as well as 2 side infrared range detectors. The radar, placed on top of the robot, searches the area infront of the moving robot for obstacles. If one is located within close proximity (30cm), the radar scans the area (rotates with the use of a motor) for any other possible paths which contain no obstacles within range. The 2 side IR range sensors make sure that if something misses the range of the radar, a side collision won’t occur.”

This Ruler Clock looks like it would have been tons of fun to build. It uses a few stepper motors that are driven by a motor shield that is connected to an Arduino.  Nice thing about these small steppers that are used in this project is that they can be found for free everywhere you look. Next time you see one of those disposable $50 printers being tossed out because the ink refills cost more than the printer is worth think about the small steppers that are hiding inside. Scanners and floppy drives are also gold mines when hunting for free steppers.

“The brains:

• Arduino with Adafruit motorshield – This is definitely overkill, and I used this simply because I already had it.  If you have an Arduino compatible board that isn’t otherwise gainfully employed, then it’s quite easy to whip up a circuit using L293 ICs on breadboard that will drive a couple of stepper motors. Look here: http://www.tigoe.net/pcomp/code/circuits/motors/stepper-motors, for circuits for driving steppers from an arduino.
• The logic/timing part of the code would be the same for all versions, but the interfacing code will be a little different.
• Any Arduino compatible board will work fine as far as I know.
• 2x Stepper motors.  I tested this will some dead cheap little steppers that have almost no torque and only 20 steps per revolution.  I paid next to nothing for them.  I also made a version with some good quality NEMA17 steppers with 400 steps per revolution.  I paid about £14 for each of those. I ended up using the cheap small steppers.
• In the Arduino code, modify the value “stepsPerRevolution” to reflect the kind of motor you have.
• You’ll also need a power supply, maybe two if you have big beefy motors.”

The prize this week is a pair of wire strippers, this will this will help you prep your cables to be attached to your next great creation. This contest will run for one week (December 18 – December 24, 2010). Ending time is based on central standard time. To enter, identify the item pictured above and give an example of what can be done with it.

Please do not give the answer in the comments.

Send an email to contest @ hackedgadgets.com with “Name the Thing Contest” as the subject, and the message body consisting of:

• The name of the item in the above picture
• An example of what the item pictured above can be used for

The winner will be chosen at random from all of the correct entries.

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Added January 1, 2011

The item to guess was Parallax Say It Module

The winner is Raleigh S. (there were 58 entries)

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Below is a picture of the prize.

If you have some old camera flashes in the closet that you can’t use with your new DSLR have a look at this project that Adapts an Old Silver Flash for use on a Digital SLR over at Rien que pour les yeux. There is a 5.1 volt zener diode in the circuit to protect the TTL fire circuit of your camera. Please follow the warning on the site that mentions the dangers of attaching an old flash without a converter to our modern camera which could cause permanent damage.

Via: HG Comments

This is a bunch of electronics that have been taped together to emulate a sentry gun. It is supposed to scan looking for the range of an object and when something moves it is supposed to stop and speak a command to what just moved. It doesn’t quite work properly but I am sure we will see it working a bit better in the future. The Parallax text to speech chip looks to work very well (looks like it has been discontinued). The voice phrases are recorded to the memory on the Arduino and by the sounds of it there are a ton of phrases in there! If you are looking for some inspiration to work from this might be the project to do it.

Sean Chen and Yunchi Luo packed some cool 3D Pong Game Play into 3 Altera DE2 Development boards. Two digital cameras have their composite outputs feeding into the game hardware. They are using the image in the game and the system is monitoring the image for the colored paddles.  These represent just one of the many great ECE 5760 projects.

Thanks Bruce

“The game software runs on a third DE2 board that acts as a master, which is connected to the two slave boards via GPIO and controls graphics as well as arbitrates game state. To create the scaled-down version of the picture, we piggy-backed off the VGA controller’s read requests to the SDRAM. For every 4 pixels and every 4 lines, using the VGA controller’s X and Y scan coordinates, we wrote the pixel colors into SRAM, scaling the address to the size of the picture-in-picture window. Then, when the VGA controller requests a pixel inside the picture-in-picture window and no game objects are in front, we compute its position in the SRAM and give it to the VGA controller. The SRAM had to be dual ported for this to work, and we simulated the dual porting by running the SRAM at twice the VGA clock and then reading and writing on alternate cycles. “

If you want to learn how to work with IR over long distances have a look at the article that Giorgos Lazaridis wrote. He uses 555 timers to generate the carrier frequency needed for the IR reciever which is the type you would find in a DVD player or a TV set (amongst a million other remote controlled things). Giorgos is getting a very healthy 10 meters of range from his system.

“The first part of the 556 (IC1A), generates pulses of about 1.5 msec duration, with 30 mSec interval (signal frequency is about 32 Hz). The second part, generates the carrier signal which is 38 KHz. The transistor Q1 switches the carrier signal (38 KHz) on and off, according to the previous (32Hz) signal. In simple words, the IR LED receiver a pulse train of 38 KHz, 32 times per second (32 Hz), each time for 1.5mSec. “