Yu Jiang has put together a sweet robotic arm that track’s his arm and hand movements pretty well. The arm its self is constructed using a Lynxmotion rotating base, servos, raw materials, and some aluminum scissors and spoons for the fingers. On the tracking side I have to assume the 3D tracking is done with the Leap Motion control device, the arduino is controlling the servos and node.js is used to tie it all together.
This has been a pretty well-lit target of the mass media, 3D printing firearms. And regardless of if you are for it, or against it, I’m not really into politics so … it’s emerging technology and its amazing. If you’ve ever fired up a 3D printer and printed your own model, you can appreciate the structural engineering that goes into making a gun that actually fires.
About a month ago there was some news of a 3D printed handgun, but this is the first rifle that I’ve seen fire. It’s only a single shot, and its a pretty light-weight bullet. I can’t say much for the safety on this one either seeing how the guy is using a string to fire it and hopefully is hiding behind a wall :)
What I personally would like to see is to take a step backwards and 3D print a custom cap gun (do they still make cap guns?) or those toy guns that used to shoot the little yellow balls.
The implementation goes pretty low-tech, with wire, rubber gloves, and electrical tape. The contacts are being fed into a hacked up usb gamepad, and interpreted by a php script reading the usb port. Part of what makes this hack unique is the encoding method, which I’m sure would take some practice to get right but you have to try new stuff to push innovation, right ?
I love how this article starts out, the age-old saying about RF and analog being taboo… so true! Anyhoo, Colin takes you on a quick rundown of antenna basics, focusing on tuning PCB antennas. This is one of those articles you see AFTER you need it, personally I totally could have used this months ago. So we’ve all seen these PCB antennas, those little squiggly lines on your board that do the voodoo RF magic, but what do you do when you need to tune it ? Well start by reading this article.
With the recent boom of cheap SDR’s flooding the market, more people are getting back into RF design. Although I wouldn’t recommend using a fixed-tune antenna for a SDR, the theory by its self is worth the read. Of course the biggest hurdle here for a DIY’er is going to be having access to a spectrum analyzer.
The guys over at SuperHouse have really done their research. In the video, they explore just about every option you have for powering your network cameras. From the obvious, to the not-so-obvious. I’ve seen hacks before, and done myself, which is simply use the unused pair of wires to basically ‘extend’ your power adapter on a high amperage bus, then split again back at the camera. But what I haven’t tried is using a real POE injector, then using a small 5v switching regulator at the base. The beauty of doing it this way, is you avoid the dropout you are going to occur by simply running 5v on the other pair especially over long distances. In the video most of the time is spent doing this option, which is really neat because basically they take a really cheap foscam ip camera and essentially turn it into a more POE camera.
Another really green idea would be to cut the wires completely, and I do mean all of them. Use a solar cell, and a battery and power your WIFI camera from that. You would obviously need to be in a place where you could get ample sunshine during the day to charge the battery for nighttime use, but the concept is solid.
Dave Akerman wants to shoot his Raspberry Pi into the sky on a balloon. In order to do that the Pi has to run on battery power. Dave dives deep into the core of the Raspberry Pi’s power configuration and decides that unless you are running a USB device that needs 5v, you can power the Pi on as little as 3.3 volts. Now I can appreciate any article that starts out with a disclaimer about voiding your warranty! Dave strips off the on-board linear regulator and goes through the option of wiring up your own LDO (possibly more efficient) or using a switching regulator.