[Eric] sent in this very informative writup on how to use Photo interrupters. These things can be used for many things, he lists pellet dispensing and limit switches. He found one in his junk box and realized he knew very little about it. After some exploring and research, he’s here to educate the rest of us. There’s a good breakdown of the circuit itself which is pretty simple as well as a test circuit and some sample code.
Strobit looks like it could be a project to keep an eye on. The entire project is open source, including the hardware. The aim is to build a low cost, low power, wireless enable arduino powered widget. This seems like it could really cut down on the development time of many projects we’ve seen here. Development is still ongoing but it looks like they’ve already implemented some mesh networking similar to the zigbee systems.
has put together this interesting project involving aluminium can recycling (translated, sortof). They’re using an arduino to tally up how much aluminium they have accumulated. That information is then passed on and displayed on a google map. There are families that go around collecting the cans as a means of income, and this system could be very helpful to them. They state that their goal is to eventually have restaraunts and more families included. We’re a bit curious about how helpful this really is. How is that information actually changing the actions of the collectors? Would a simple flag on your door or window signalling enough cans to pick up or not be just as effective?
Researchers at UC San Diego have been working on a robot that learns facial expressions. Starting with a bunch of random movements of the face “muscles”, the robot is rewarded each time it generates something that is close to an existing expression. It has slowly developed several recognizeable expressions itteratively. We have a few questions. First, are we the only ones who see a crazy woman with a mustache in the picture above? Why is that? What makes [Einstein] look so effiminate in that picture? Secondly, what reward do you give a robot? You can actually see this guy in action in a video after the break.
For those who watched the Tour de France, you may have been pleasantly surprised to see some cool tech. Nike was using a robot to paint pictures on the street in chalk dot matrix style. It was accepted by the general public as new and innovative, as well as generally cool. In the hacker community though, a bit of trouble began to brew. The Chalkbot bears more than a passing resemblance to a project called GraffitiWriter. GraffitiWriter was a bot initially designed to protest the militarization of robotics. As it turns out, one of the early developers of the GraffitiWriter is behind the Chalkbot in a legitimate contract. The trouble doesn’t seem to be one of intellectual property legalities. People are mad at the corporatization of public work. They want kids watching to know that this system was designed by regular people in their spare time at their homes, not by a team of researches in a secret underground Nike laboratory.
The article takes a bit of a turn and talks some about the possibility of projects being taken and used for corporate advertisement. The specific item they are talking about is the Image Fulgurator which secretly projects images on objects in your photographs. You’ll have to go check that one out to see how it works.
Some companies insist on using proprietary pieces. It can be really frustrating when there is no apparent reason other than consumer lock in. It irritates us to feel like we’re being forced to buy their pieces. This is one of the more popular reasons listed when you ask a hacker or modder what got them started. This project takes us through making a normal power supply work with the compaq proprietary 14 pin plug found in some smaller desktop PCs.
Aside from the plug itself being different, the motherboards require a 3.3v standby voltage. A normal power supply usually only has a 5v. Though there are even simpler ways of bypassing the issue, he chose to put an inline voltage regulator. Schematics are available on the site.
These 15 ton robotic arms can reach 16 meters. Not content to control them by a simple joystick, the team hacked together WiiMote controls for them. Ok, we get it. Everybody loves the Wii. What is different about using the WiiMote in this scenario? You can see that they are only using the pitch, yaw, and roll. They’re not utilizing the tracking aspects at all. The only difference between the WiiMote and their joystick in this scenario is that the WiiMote connects via bluetooth. Frankly, we just like the fact that people are playing with the robotic arms, WiiMote or not.
This tiny bot wants to go inside your body. That’s right, it was designed to travel through veins. The little bot has no on board propulsion system. It is controlled by a magnet outside the body. See those little spines? Those straighten out to keep the bot in place when it isn’t supposed to move. Creepy right? In all the articles we’ve seen on this bot, there aren’t any details about what actually is on board. They mention adding a camera in the near future, but why are they calling it a robot? Surely there’s something cool in that little body. This is a quite practical application of a project we covered recently. Commenters weren’t impressed with the external control system, likening it to the old vibrating football player game. Well, here’s where it could be usefull.
We would like you to meet PR2. Made by Willow Garage, PR2 is a platform for research into robotic programming. The bot itself is simple compared to some of the humanoid bots we see, but its behavior is quite complex. In the video above, you see PR2 completing milestone 2 of its development. This includes navigating an office with closed doors and plugging itself into a standard wall outlet for a charge. We’re especially fond of the “wiggle”. You can hear some of the developers talk more about PR2 and its completion of milestone 2 in the video after the break.
Here’s an interesting WiiMote based project. [Mans] is a tennis fan, though a bit out of practice. With the tennis season coming to a rather climactic end, he got excited and wanted to brush up on his skills. He found the toss part of his serve to be very sloppy. Being a hacker, the first thing he thought was that there must be some way of tracking and graphing his toss so that he could improve it in an intelligent and controlled manner. The WiiMote seemed a perfect fit for this. Only a small modification was necessary, an external button wired to the internal “-” button. This switch is active while he’s holding the ball, and inactive when the ball is released. In this manner, he can track and chart his toss to find out exactly where he needs improvement. He uses [Johnny Chung Lee]’s code, with a small but unspecified modification to write the accelerometer data to a text file.
As he points out, this could be very usefull for any repetitive movement. Whith accelerometers getting cheaper and cheaper, there’s nothing stopping you from using multiple ones either. Imagine a golf rig to analyze your swing, Maybe a boxing rig that measured your hip twist and arm extension, or possibly a yoyo glove to tell you if your flick needs some help. Great job [Mans].
[Chris] wrote in to tell us about this project he did while living in the dorms. He built a system to automate his dorm room door. It handles unlocking and opening/closing the door via iPhone, secret knock, and even the key. The lock/knob portion is handled by a servo while the opening/closing action is hydraulic. After living with it for a year, he says that it never gets old, but there were a few bugs. Apparently it would randomly open in the middle of the night sometimes. If you’re interested in doing something like this, but not damaging the door, maybe you should check out the RFID dorm door lock project.
Here’s an interesting concept, the bot pictured above has no internal control mechanisms. His claims to have built the smallest bot are dubious, considering it requires a much larger control platform to function, so lets just set that aside and look at how it works. The bot itself is basically a hollow box with a hinged manipulator mounted on it. He has then built a modified CNC type structure with various magnets below a platform. The magnets can move the bot and control the manipulator (assuming the bot isn’t trying to pick up anything magnetic). He talks about this being a possible control scheme for smaller bots, though we think he would have to make some major advancements to his magnetic controls for accuracy’s sake. As for his claims of being the smallest, well, we’re sure we’ve seem similarly sized bots, even hexapods, that were completely self contained.
Here’s something every office probably needs. Ours does at least. It’s a WTF counter. When the office gets just a little too weird, someone hits the button and it gets logged. It’s probably pretty easy to judge the day by the WTF chart. The button is connected to an Arduino that updates the status on a local web server. We can imagine a nice bar graph of WTFs per day, or possibly a pie chart with normal time vs WTF time. Unfortunately, imagining is all we’re going to do. They didn’t include any examples of the visualizations. Can you imagine saying something to a co worker just for them to promptly march over and slap the WTF button? Maybe we don’t need one.
