Fritzing (Shift registers & LEDs)

I use Frizing to sketch what I want to do before starting building actual circuit.

Fritzing is an open-source hardware initiativethat makes electronics accessible as a creative material for anyone. We offer a software tool, a community website and services in the spirit ofProcessing and Arduino, fostering a creative ecosystem that allows users to document their prototypes, share them with others, teachelectronics in a classroom, and layout andmanufacture professional pcbs.

Figure1. Schematic

Figure2. Breadboard

Then, start building!

Figure3. Building

See Fritzing: http://fritzing.org/home/

Test RGB Leds

After soldering, I was trying to test RGB Leds to see if they works.
(I use 3 shift registers and 8 RGB Leds.)

Just a piece of code for using three 74HC595 shift registers to count from 0 to 255 which can control them to change colours.

colour changing

The shift register gives 8 outputs which each of them driving a LED, thus controlling a total of 8 LEDs. But the good thing is that it needs 3 inputs only; namely data input, clock, and latch. This means that we manage to drive 8 LEDs with 3 output pins from Arduino board.

74HC595 shift register

The 74HC595 shift register pin layout

Reference

http://arduino.cc/en/tutorial/ShiftOut

Soldering

It's quite hard for me to solder them cus I never soldered anything before. Lots of things should be concerned for safety.

Soldering Iron Safety 

• Never touch the element or tip of the soldering iron. They are very hot (about 400°C) and will burn.  Actually, I use 300°C when soldering.
• Hold wires to be heated with tweezers or clamps. 
• Keep the cleaning sponge wet during use. 
• Always return the soldering iron to its stand when not in use. Never put it down on your workbench. 
• Turn unit off or unplug it when not in use. 

Soldering Safety:

http://naples.cc.sunysb.edu/Admin/HRSForms.nsf/pub/EHSD0348/$File/EHSD0348.pdf

GSR sensor

Got a GSR sensor from my lecture.

GSR(Galvanic Skin Response) measures the electrical conductance of the skin between two points. As you can see from the sensor consists of two electrodes, one is placed on the index finger and on the other the average of the non-dominant hand.

Human has the positive electrode and the negative.

GSR sensor

The Galvanic Skin response was used in the bio feed back game Wild Divine and could be a good tool to include into a complete biofeedback system.

See more:

http://www.cooking-hacks.com/blog/how-to-acquire-physiological-signals-with-arduino-and-measure-stress-with-e-health-sensor-platform

http://open3.cc/wiki/doku.php?id=bio_feedback

Wearable technology

Wearable technology is a transitional stage between imagination and reality. What we have thought were practicable but haven't become reality yet.  Wearable technology is a new application environment for electronic and computing devices.

Wearable devices are taking the world by storm.

1. Wearable Glasses will be utilized to record and assess in-person interviews. Once someone passes their interview through HireVue or TakeTheInterview, an in-person interview will be established with a recruiter or hiring manager. By equipping themselves with a device, such as Google Glass, the interviewer could record and gauge the applicants responses to questions. All types of data can be measured and stored for current and future purposes. Simple reactions to certain questions could alert the recruiter to whether this person is a good fit for the position or not. 

2. Wearable watches or beacon enabled phones could allow for accurate time tracking of employees. Are they where they are supposed to be? Can an employer cut down on fraud my having a second time clock gauge? I think so. 

3. Wristband or Bracelets, think FitBit, could monitor the health of employees while working at strenuous jobs. Imagine a HR manager monitoring 200 carpenters at a worksite. If the heart rate of one of the employees is dangerously high, why not send them a buzz to take it easy? Might cut down on a potential heart attack and worker’s compensation.  

See more: http://www.recruitingblogs.com/profiles/blogs/how-will-wearable-devices-impact-hr 

RGB LEDs

Dada, RGB Piranha 5mm is what I got.

RGB LEDs producing different colours in one application

Longest lead (pin 2) is Cathode (-)

Pin 1 -( emits light of 650nm) Green - Short Lead (same length as Green)
Pin 2 - Negative/Cathode Longest lead
Pin 3 - CB (emits light of 470nm) - Blue - 2nd longest lead
Pin 4 - BG (emits light of 520nm) - Red - Short lead (same length as red)

Pin 2 (longest) is the common cathode to all 3 colors.

Read more: http://www.divilabs.com/2013/04/multi-color-leds-beginner-level-guide.html#ixzz2yINjX5cl

shift register controls LEDs

I got 3 shift register chips with Arduino to control 8 RGB LEDs for my final project :). After watching tutorials, I found something interest. 

In this project by Davide Coppola, an 8-bit shift register is controlled to animate a short strip made of 8 colored LEDS.
The animation is the simplest possible: only one LED at a time is ON and the one which is ON moves back and forward bouncing from one side of the strip to the other.

http://www.nudatech.com/blog/using-a-shift-register-74hc595n-with-arduino/