If you have some old donated scanners and printers chances are you have most of the stuff needed to make your own DIY Laser Engraver. The main thing that all laser engravers have in common is a method of moving a laser or set of mirrors in an X Y pattern. Scanners and printers have motors and rails that can allow for accurate motion so all that is needed to be added into the mix is a control system, some motor drivers and the laser system. ianmcmill shows us how he did it using an Arduino and 90 € of other various parts.

With this setup you can see below what it is able to do.

“It is able to cut :

• foam rubber
• tape
• vinyl
• paper (nearly every color but white/red)
• several plastics (could require several runs depending on thickness)

It can engrave:

• light wood (Balsawood/Poplar)
• leather
• bone
• horn
• plastics
• some varnishes
• blank cds/dvds (purple/blue)”

Our friend Bob Davis has hacked another LED sign, you can see it above connected to an Arduino. Check out his article to have a look at the code to see how it works. There are lots of these LED panels available on Ebay that are ready to be repurposed for your next project.

Red Bull has selected their finalists in their latest competition. Have a look at the cool entry above by North Street Labs, it is a huge tic tac toe game. You stomp on large buttons in the center of the game board to register your space selection. The buttons are great, they are made from plumbing parts and some old bed springs. The use of RGB LED strips really makes the game stand out. Be sure to check out all of the other entries at the Red Bull Creation site and see them in person at the Northside Festive in June.

Our friend Max from Zedomax has introduced a new wireless mic to his video recording setup. If you make videos and need some distance from the camera his review of his new mic is sure to be of interest. He picked up a Sennheiser EW122PG3 which isn’t cheap but check out his video at the 10:20 mark where he demonstrates the range and clarity during a tarp board demo. If you hadn’t heard of tarp boarding before I was in the same boat…

This Magic Wand project can be used to get someone young interested in electronics since instead of simply doing something practical this project appears to be magic. The project uses a magnetic reed switch and a magnet embedded into a magic wand to turn things on just by bringing the wand close to them. There are a ton of possibilities here such as hiding the magnet between your fingers and amaze your friends that you have the ability to turn on the items just by the force of your hand and they don’t.

Thanks for the tip Jason.

The prize this week is a breadboard power supply. This contest will run for one week (May 11 – 17, 2013). Ending time is based on central standard time. To enter, identify the item above and what it can be used for.

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.

Below is a picture of the prize.

For this Cornell ECE 5760 Hand Tracking Pong project Hanting Lu and Kedari Elety have connected a camera to an FPGA, the image is down sampled so that it is only looking at a 40 X 30 image to determine how the players are moving.

“The NTSC video signal from the camera is stored in the SDRAM at the rate of the TV Decoder Line clock (TD_CLK). Data is read from the SDRAM each time the VGA requests data. The data from the SDRAM is in YUV format which needs to be converted to RGB before sending it to the VGA. For skin detection, we added a filter at this converting module level such that in addition to the R,G and B values, the module also outputs a one bit binary 1 if it corresponds to a skin pixel. Else, zero. By doing this, the output on the VGA is now white corresponding to skin pixels and black otherwise.”

Most of us toss away our car and boat batteries when they no longer start our vehicle in the winter. Most of these batteries are now advertised as maintenance free lead acid, even though the electrolyte often still dries out. Youtube user Redicety12 shows us how you can bring them back to life by cracking the tops off the battery, dumping out all of the old electrolyte out, rinsing with a baking soda and water solution, then a second water only solution. Now that it is clean he fills it with alum water.  After a trickle charge the battery is brought back to life. Probably is not as good as new but will probably give you some additional usable life.

Dimitri, Frank, Kevin and Robin from Eectronique have sent in some details of a project that they have been working on. They had an old early 90′s LED matrix sign and wanted to make it work with a Raspberry Pi. The circuit layout is what you would expect from that era.

Read More: Old Display Reverse Engineered to work with a Raspberry Pi

Google Translated version.

“I was able to retreive an old (1992 !) bus display (the thing that says the next stops on the buses). It was old: unknown protocol, unknown wiring, not fast at all, etc..

I brought it to the university (uni of Geneva), and, with some friends, we decided to hack it. As we had some RPi’s laying around, we thought it would be cool to hack the display and connect-it to the RPi: we could then be able to display the date, next bus stops, some jokes, etc .

The display itself is very old school: all the cathodes pixels/led on a line are connected to shift-registers (daisy chained). then, the anodes of the LEDs of each line are connected to the transistors. So to display a string, you first have to send the first line, then power the first transistor. Then clear the line, send back the second one, power the second transitor, etc.. Is was very simple to connect to the RPi as the signal is only going from the RPi to the display, so we didn’t had to do voltage-level conversions.

We then wrote some software (in C: the git repo is on the website), to handle the protocol, the sending and a deamon that listens on a pipe.”

If you would like to be a super hero for a day, this Titan Arm can make it happen! They have milled the exoskeleton system out of 6061-T6 aluminum. It hasn’t been all smooth sailing, check out this video of the mill crashing when some wrong coordinates were entered by accident. The technology and testing behind the arm is extensive. They have attempted to design it in such a way that it feels intuitive to use.

Via: Hackaday

“One way of creating a natural user experience is to give a quick, smooth response to the user input.  This is no small feat; how can you tell when a user requires additional strength?  Electromyography is a potential solution.  Electromyography, or EMG, is a way of sensing muscle activity through electrical signals.  When muscles are activated by the brain, an electrical potential can be measured in the range of 50uV to 30 mV.  By amplifying and filtering the signals, it’s possible to read and decompose the signals.  When the muscles are inactive, the electrical potential is low; however, when lifting an object, the electrical potential rises.”