Makieks spent about 30 hours and $65 building this Pearwood Computer Case. You can see a video of the original CAD design here. The water cooling system sight glass under the wooden buttons really makes the system look fantastic.

We featured an interesting CNC Halftone Picture technique that was done by Metalfusion. I have seen lots of people making halftone images using Photoshop since it has this capability built right in. If you don’t have Photoshop Metafusion has made a program which lets you import a picture and export a halftone DXF file. I wanted to give it a try but instead of using the CNC machine I wanted to use the CO2 laser cutting machine.

I cropped a picture of my daughter and created a DXF to cut on the laser out of 3mm Baltic Birch Plywood, it was large and took a long time. As soon as it was complete it broke apart in some areas because I forgot to take the laser cutting kerf into consideration. Unlike a CNC machine which machines in a way that takes the width of the bit into consideration when generating tool paths, the laser cutter simply cuts along the lines provided. I scaled down the image and reduced the size of the circles slightly and it worked great. To get the full effect you need to paint the wood black, since it was laser cut the inside of the circles and the cutout was already brownish black so only the face of the plywood needed to be painted.

I also wanted to see how it looked when it was cut out of black construction paper. This would allow the speed of the cut to be much faster and since the paper was already black no further processing would be needed. The power was a bit low so I needed to punch out a few straggling cutout holes, a few puffs of compressed air took care of that with ease.

You can see the video of the process and some additional pictures after the jump.

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This Double Sided Microcontroller Controlled PCB Exposure Box uses a PIC 16f268 to time the exposure LEDs on for the entered exposure duration. You can select if you are doing a single sided or double sided board, then you set the exposure time you need. After this you just sit back and relax while your board is getting perfectly exposed. We have seen some exposure boxes before including this UV LED exposure box project but I must say I prefer the controller on this one.

“If I had to expose a double sided pcb with my previous exposure box, I needed to turn it on twice. (1 time for the top, and 1 time for the bottom) To solve this problem it was time to build a new version. This new version will do the 2 side’s at once.”

Kerry Wong shows us a project that allows for accurate Milliohm Measurement. For day to day applications your trusty hand held multimeter will probably do just fine, but when you need to make a very accurate low resistance reading this circuit is sure to help you out.

“I used the reference design for the unity-gain difference amplifier AD8276 and a precision Op-Amp AD8603 from Analog Devices to form the precision constant current source. An AS431 precision shunt voltage reference is used for the 2.5V reference voltage. Using this design, the constant load current is Vref/R2. R2 (250 Ohm) will need to have relatively high precision in order for the load current to be accurate. If you are using other precision voltage references, the value of R2 will need to be adjusted so that Vref/R2=10 mA.”

A walking robot like MABEL might not look that interesting to many people since humans do it all the time with no effort but when you think of the complexity behind what is being done in the video above you have to admire the machine!

Thanks for the tip Fahd

Via: Engadget

“MABEL runs free for over 110 steps! In our opinion, this is the most realistic, human-like running achieved on a robot. It has a very satisfying feel to it. The robot just moves right. It is up in the air for more than a third of the duration of step. The height off the ground is right. Whereas other robots had their feet maybe one sixth of an inch off the ground, MABEL is 3 to 4 in inches in the air. The motion of the hip, which is like a bouncing ball, and the pitching of the torso give you the sensation of running. It all just makes you say, that is running.

MABEL has four electric motors, two for each leg, which provide power. Whether the robot is walking, running, or just standing, there is a feedback controller on a computer that measures all of the positions of the robot’s joints and the angle of its body, and then determines the proper power commands to send to the motors.”

This project by Robotics / Electronics / Physical Computing is an Airsoft RC Tank that Tracks the Enemy and Fires at them. Using IR LEDs on a target and a LEGO NXT brain the robotic tank drives around looking for the target. The tank doesn’t hit anything because it has an ultrasonic sensor in the front to sense the distance from objects. A Wiimote camera is used to look for the IR light on the target. When the target is found the tank positions and fires. You can see the first video below where the tank tracking code is demonstrated and the second video where the fully autonomous tank is shown in action. This builds on many other projects , check out how the Wiimote camera is connected to a LEGO NXT computer and version 1 and version 2 of the tank.

Thanks Dan.

We have seen quite a few Nintendo Nunchuck hacks. The Nunchuck is a great piece of hardware for hackers since it packs lots of great sensors and switches in a nice looking, functional package and best of all they are cheap! The LVL1 Hackerspace decided to use a Nunchuck in a Fire Breathing Pony project that they brought to Maker Faire Detroit. There isn’t much details on the build yet but I am thinking that will change in a week or two.

Via: Hack a Wii