DIY, Electronics

DIY concrete lamp with switch and power outlet

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Today I finished my new project, a concrete lamp with power outlet and switch for the lamp. Usually, you will only find the one or the other. Actually I’ve built a concrete lamp before butwithout the switch and a power outlet.

To build the lamp, i followed the instrocutions of this youtube video. I used 5 pieces to build a 13cm*13cm*13cm cube. I mounted two flush boxes to hold the power outlet and the switch.

If you don’t know what you’re doing, don’t do it! Attention: Concrete might actually be conductive!

Mounting the boxes was actually more difficult than expected because the boxes overlapped by half a centimeter so I had to trim of a bit. I drilled holes for the screws to hold the boxes in place. I also used some quick concrete to seal the gaps so that no concrete could enter the boxes.

After the concrete dried (like 4 days), I carefully drilled the holes to mount the outlet and switch. Make sure your switch is a two-pole switch! Otherwise your lamp socket would eventually still be connected to phase depending on which way you plug in the power cord! Afterwards I applied two coats of concrete sealer.

Finally, I only had to connect the plug to the wire. I used white again to match the overall design which turned out to be a good choice I think. I used white heat shrink tubing as protection of the fabric cord. And finally …tada: done! Feel free to copy and comment!

 

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Electronics

HSV RGB IKEA lamp + IR Remote

My first Awesome IKEA lamp had multiple trimmers and push buttons to setup speed, brightness and color. I now added a remote control to get rid of all these. I chose one of these common rgb remote controls that are shipped with every other cheap rgb lamp. I got it from dx.com. The led i use is a 3W rgb star led from ebay with the following specifications:

Red=2,4V, Green=3,4V, Blue=3,4V, 350mA per channel

Make sure you do not get one with common “+”; if so you can’t use p mosfets but must use the n version instead. Common ground is no problem. You’ll get a complete partlist from the eagle file. The main changes from the original layout are:

  • P_MOSFET: IRLML6402
  • IR-RECEIVER: TSOP 31238
  • IR_REMOTE: CR2025

hsvrgblamp1.0

I uploaded everything including the schematic, board and the code: Download!

The code is neither commented nor nice. Feel free to improve it 😉 There is a little problem with this version; the p-mosfets seem to have great leakage current so the leds wont turn off completely. I think the PORTD has to little output power…

Electronics

Awesome HSV RGB IKEA lamp

When my girlfriend gave me her birthday present, i was overwhelmed. The drawing was perfect, I loved the motive, details and shadows. And it came that she had her own birthday! This was the moment i decided not to buy one of her wishlist’s entrys (yes i keep track) but build something by my own too (let’s just stick to buying things okay?). I thought about painting a picture too but decided against it. I just didn’t want to reveal my inner artist and make her jealous.

Since im a student of it and electronics, i chose to build something wired.  It had to be cool but also instructive for me i though. I always planned on building a “proper” RedGreenBlue LED Lamp which could fade between colors. But i never found the time nor the motivation to do something símilar in my freetime. The first attempts on my Arduino Board were pretty basic. The colors were fading, yes, but randomly which means (in RGB color space) pretty white changes to a white reddish to bright white reddish to a bright white reddish with a touch of green or blue. This wasn’t  that exciting at all. I “went” to the mikrocontroller.net community and asked about color spaces. My idea was to make a distinction between color and brightness and avoid same colors with just different portions of white. I found that the hsv (hue saturation value) color space met my needs. It allowed me to use a simple potentiometer for choosing the color (hue) and a further one for the brightness, while the saturation remains constant (no white parts please ;-))

I started coding (checkout github) the code for an atmega8 controller and tested it on a breadboard first. I found and bought a perfect fitting aluminium globe at IKEA which could hold both the led and the electronic circuit. Then I began with the final board layout in Eagle and ordered the other parts at reichelt: Three Potentiometers (two logarithmic ones), three nmos transistors, resistors, capacitors, push buttons, toggle and finally the power supply (5V2A).

I attached the parts to the new board and tested it with Georg who provided an oscillocope and even a 3D printer. I  designed and printed two plastic parts for the globe to hold the led and the board.

Also I changed the original design from a standing lamp to a laying one. I though it would look nicer and lighten a wall much better. Also the potentiometers and buttons were better accessible (It’s not a bug it’s a feature).

Everything looked fine but a random flashing which disturbed me. One user from the forum gave me hint that there could be something wrong with my code since he had the same problem in the past. So glad this guy read the post -> no flickering anymore!

During the project i learned a lot about the whole progress of implementing a vision. I really started with a vague idea and then made use of a great toolchain (3d printing, uC development, board layout in eagle, testing testing and testing with oscilloscope)… Also i must say that there were a lot of coincidences like a broken diode and a wrongly connected mosfet which i eventually hadn’t noticed in other places… Maybe you (Kenzie) remember that i was happy about the one day on skype? Yeah, i figured the board was actually working … so this was my last week; for you! be happy!

Looking forward to party in fading colors!

Reference:

https://github.com/kreuzUndQwertz/hsv2rgb (code and board layouts as well as the openscad 3d designs)

http://www.mikrocontroller.net/topic/262143#postform (thread on rgb space and flashing issue)