Of all the things evolution has stumbled across, the eye is one of the most remarkable. Acting as sort of a ‘biological electromagnetic transducer’, the eye converts incoming photons into electrical and chemical spikes, known as action potentials. These spikes then drive the brain of the host life form. Billions of years of natural selection has produced several types of eyes, with some better than others. It would be an honest mistake to think that the human eye is at the top of the food chain, as this is not the case. Mammals underwent a long stint scurrying around in dark caves and crevasses, causing our eyes to take a back seat to other more important functions, such as the development of a cortex.
There are color sensitive cones in all eyes. Mammals have three types of cones, which are…wait for it…Red, Blue and Green. Our red and green cones are relatively recent on the evolutionary timescale – appearing about 30 million years ago.
The way these cones are distributed around our eyes is not perfect. They’re scattered around in lumpy, uneven patterns, and thus give us an uneven light sampling of our world. Evolution simply has not had enough time to optimize our eyes.
There is another animal on this planet, however, that never went through “the dark ages” as mammals did. This animal has been soaring high above its predators for over 60 million years, allowing its eyes to reach the pinnacle of the natural selection process. A bald eagle can spot a mouse from over a mile away. Birds eyes have 5 types of light sensitive cones – red, blue and green like our own. But add in violet and a type of cone that can detect no light, or black. But it is the way these cones are distributed around the bird’s eye that is most fascinating, and the subject of today’s article.
Continue reading “Hyperuniformity — A Hidden Order Found in the Greatest Set of Eyes”
If you’re looking to build the next creepy Halloween decoration or simply thinking about trying out OpenCV for the first time, this next project will have you covered. [Glen] made a pair of giant googly eyes that follow you around the room using some servos and some very powerful software.
The project was documented in three parts. In Part 1, [Glen] models and builds the eyes themselves, including installing the servo motors that will eventually move them around. The second part involves an Arduino and power supply that will control the servos, and the third part goes over using OpenCV to track faces.
This part of the project is arguably the most interesting if you’re new to OpenCV; [Glen] uses this software package to recognize different faces. From there, the computer picks out the most prominent face and sends commands to the Arduino to move the eyes to the appropriate position. The project goes into great detail, from Arduino code to installing Ubuntu to running OpenCV for the first time!
We’ve featured some of [Glen]’s projects before, like his FPGA-driven LED wall, and it’s good to see he’s still making great things!
Continue reading “Googly Eyes Follow You Around the Room”
This is just one example of several pairs of spooky eyes which light up [Vato Supreme’s] bushes this Halloween. The quick and inexpensive build process make it a perfect diy decoration.
Each eye is made up of a ping-pong ball and an LED. But that alone won’t be very spook as the entire ball will glow rather brightly. So he spiced things up a bit by masking off the shape of a pupil and spraying the balls black. The vertical slit seen in white above will glow red like a demon in the night.
The LEDs are driven by an ATtiny85 running the Arduino bootloader. [Vato] found there was plenty of space two write code which fades the eyes in and out using PWM. This happens at random intervals for each of the four pairs he is driving.
We’ve seen a similar project that used oversized LEDs as the eyes. But we really like the idea of using a diffuser like this one. See it in action after the break.
Continue reading “Halloween Props: Spooky eyes light up the bushes”
To decorate the office for Halloween [Eric] decided to make [Vigo the Carpathian] stare at passersby. We hope that readers recognize this image, but for those younger hackers who don’t, this painting of [Vigo] played an important part in the classic film Ghostbusters II.
In the movie, his eyes appeared to be following anyone looking at the painting. [Eric] grabbed a Kinect and used Processing to recreate the effect in real life. The image is displayed on an LCD screen. A bit of work with Photoshop allowed him to cut out the eyes from the image, then create sprites which are moved by the Processing sketch. It’s reading data from the Kinect (so it knows where to ‘look’) which you can see perched on the top of the cubicle wall. The illusion is delightful, see for yourself in the clip after the break. We’ve already watched it a half-dozen times, and it looks like it was a real hit with the guests at the open house.
Can you believe they threw this together in just one day?
Continue reading “[Vigo’s] stare follows you wherever you go”
[Matt Daughtrey] sent us this sweet little project he’s doing for Halloween. He’s building some animated LED eyes. He says that the whole thing is 3 individual LMDriver platforms, another project he’s working on. There isn’t any info available about that, but he does expand a little. He states that each display module uses an Atmega169 with some heavy multiplexing. The eyes really don’t look that impressive sitting on the bench, but watch the video to see how cool they really are.
We noticed that the back of the boards appear to have http://www.embeddedether.net on them. Unfortunately that site seems to have been grabbed by a domain squatter.