Jesper Eklunds Blog

tirsdag den 25. december 2018

mandag den 10. oktober 2016

Lille Arkibal er en miniature lampe udført i messing og en model i størrelsesforholdet 1:3 af en klassisk arkitektlampe.

Lampen er som originalen udført med 5 stænger og 4 fjedre, har stor bevægelsesområde og kan sættes i alle positioner.

Den er lavet med hule messingstænger, hvor igennem ledning til lys er ført, ganske som på originalen.

Lille Arkibal er så vidt det har været muligt forsøgt at få til at ligne originalen.

Video:

Billeder fra tilblivelsen kan findes her:
https://get.google.com/albumarchive/109538539216190136606/album/AF1QipOSmgoq_71N57lZPPF2CUcYTlz0l3e5Xu-ugrmN

lørdag den 19. december 2015

Sjove forretninger

Kød & Elektronik

Tobak & Helse

Bilka

REMA 10000

lørdag den 23. februar 2013

Water Strobe Spirale

This is an improved version of the previous water strobe, as it now has two channels with two speakers. The speakers moves the nozzle in a x-y plane:

Here is a small video compilation of these amazing spirales:

A stereo version of the desktop controller can be found here:

Water Strobe Stereo 1.0

lørdag den 16. februar 2013

Water Strobe Signal Generator Desktop Application

If you mount a tube with running water to a loudspeaker, a strange fenomenon occurs when you film the jet of water and send a sine wave to the loudspeaker with the same frequency as the cameras framerate. I thought it would be funny with some special features for the loudspeaker signal, so i programmed a signal generator in Flex/Air , especially for water strobe filming.

Here is a picture of the setup:

And here a video where i demonstrate the features:

The software let you control several parameters: frequency/phase, sine/square modulation, sine/square amplification and volume:

The Water Strobe Signal Generator Desktop Application 1.0 can be downloaded here:

Water Strobe 1.0

The software requires Adobe Air:

Adobe Air

Enjoy!

lørdag den 10. november 2012

AC Dimmer for Arduino

Ever wanted to control a house lamp, a heater, a ventilator or similar 220/110 VAC equipment with Arduino? Here is a simple circuit that uses a standard AC Dimmer kit and controls it with an analog PWM output from Arduino. In this case a Vellerman-kit K8026 running at 220VAC. The kit has been modified, the potentiometer has been replaced by a LDR (Ligth Dependent Resistor) and C1 has been replaced by a 470nF for better adaption to the LDR range.

It works by leading the PWM output from Arduino through a lowpass filter made up by R2 and C3. This will stabilize the pwm to a steady voltage. The output from the lowpass filter is lead through an emitter follower to a LED, which is placed close to the LDR in a light conceiled compartment. The light from the LED then controls the resistance in the LDR.

This is a simple solution and requires no extra code in Arduino, but it has a few drawbacks. First of all it is not linear. This means that the usefull range is more narrow than the PWM output. Therefore you will need to find a suitable range for the Arduino output to operate. Second it has a little slow reaction about half a second, due to the lowpass filter.

NB! Always remember to be carefull with household power, and make sure that the left part of the circuit is totally isolated from the LDR and the AC Dimmer.