Assignment 2
This is the POV device I created.
The photos below demonstrate the message
and patterns generated by my POV device. The words include I, R, I, and S,
which is my name, IRIS, and the pattern generated is a smiley face.
The modification of the project I suggested
is to extent the feature of POV device which is using POV device to create a
digital clock.
The digital clock includes LEDs, a sound sensor,
strip, stage, Lilypad Arduino, transistor, real-time clock (RTC) chip, motor, isolation
jumpers, battery and wires.
Firstly, about the switching mechanism of
the digital clock. The demonstration of clock interface, which is the on and
off of LEDs of this digital clock is controlled by sound. The sound sensor
provides a means to add noise control to the clock and responds to loud noises
such as a clap of the hands. Through the on - board microphone, the sensor
detects changes in decibel level, which triggers a high pulse to be sent
through the signal pin of the sensor. This change can be read by microcontroller
boards. It can be used to detect the sound strength of the environment based on
the Transistor Amplification and the electrets microphone. ^ So that, by
clapping hands or creating a loud sound, it activated the On/Off switch. The time
is demonstrated via the sparkling of LEDs. It is convenient for users to know
the time without turning on the light inside the clock in darkness.
Secondly, the demonstration of time. The LEDs
on the strip have the shape of Roman numeral, hour, minute and second hand, which
are arranged in rotation angles for characters. They are connected to the
Arduino board, which are placed behind the plate. By connecting Lilypad Arduino
to computer through a micro USB cable, the customized code for clock can be
uploaded to the Arduino board. The Arduino drives the LEDs through a transistor
array, since the number of LEDs are much more than the POV device I created,
which would be too much to drive directly from the Arduino digital output pins.
Furthermore, the real-time clock (RTC) is a
computer clock that keeps track of the current time and the motor is
responsible for rotating strip. The clock also incorporates isolation jumpers
to the board in order to power up the Arduino stuff without the motor starting,
and vice-versa. With these components, the LEDs located at different points will
sparkle in order to demonstrate the Roman numeral, and movements of hour, minute
and second hand. As a consequence, the users can know the actual time.
Thirdly, the operation. The code of which
LEDs are going to sparkle are edited by the Arduino software and uploaded to
the Arduino board in order to represent the time. To
set the time, the users should connect the real-time clock to the related
software. When users want to know the time, they just need to create a
loud sound to switch on the LEDs and motor. Then, the clock interface will show
up via the rotation of black plate. If users no long need the demonstration, a
loud sound is required to switch off. This clock can create a false imaginary
that the clock appears in the air and will look stunning in any environment.
Using POV in demonstrating images will be a future trend since people are
fascinated in the science fiction movies and demonstrating images in the air.
^Retrieved from: http://www.robomart.com/sound-sensor.html
