POV based Magic ball

In this project, the user can ask the ball a yes/no based question and the ball will display the answer in form of a sphere which is achieved using persistence of vision. The sphere display has been created by spinning semi-circle shaped LEDs around a central motor shaft. The rotational speed of the LED’s is fast enough such that the human eye perceives a two dimensional image. The software part of the project basically calculates the refresh rates of the LED so it seems like a 2D figure. There are 19 LEDs consisting of the semi-circle and the entire display area is mapped to a 19 by 90 matrix where each element in the matrix represents a pixel. The device is powered by a ATMEGA128p connected to Led subsystem and the mic circuit. Whenever the Atmega detects an end of the question, the sphere displays a randomly generated yes/no as an answer to the question. Another feature about our device is that the LED array can generate quite bright light, people can see the display without having to turn off… Continue reading

Building bicycle pow effects with Arduino and WS2811 strips

POV displays are one great way of getting large images with only few LEDs. Spinning object with LEDs in them you can display messages, graphics and various effects. People like these things on bicycles, because it is fairly easy to build, but most important it makes you look different. Balrog-k1n have shared his bicycle POV implementation. In his project he uses Arduino to send images through six WS2811 LED strips. To give his creation interactive control and sense, he used 6+DoF sensor board which comes with Accelerometer, Gyroscope, Magnetic field sensor and barometer. Not all sensors are used here. In order to change light patterns he used neat method – since there are IMU unit, he can send control signals by taping breaks at different patterns. This doesn’t work 100% reliably, but seems it is enough to do the trick. Continue reading

RGB POV display in a tube

POV displays are fun and there are many ways of building them. Rucalgary decided to go with 64 RGB LED display in a tube. He assembled an aluminum frame where all electronics sits. POV display is controlled by Atmega1284p which have just enough SRAM for storing images. It is still initial version of software which shows demo image. He’s working on adding ZigBee (or Bluetooth) based image update. And yes, the vibration when spinning, but overall this looks great and with little balancing it is impressive piece of art. Continue reading

uPOV device with accelerometer

POV devices are great way to express yourself. These little devices use only few LEDs to display large messages. The only disadvantage is that board with LEDs has to be moved forth and back periodically. rucalgaric have shared his uPOV design which is based on AVR Atmega48a microcontroller. To synchronize displayed messages he used a Freescale MMA7660. Most of parts are SMD so its really tiny and can be carried around in pocked and used anywhere. Continue reading