June 5, 2012

Week 10

     Brightness and colors have combined to create a new MATLAB code which cycles through daylight with color temperatures and luminance.
The completed MATLAB code cycles through daylight with brightness and color temperature.

     The group will finish the final report and presentation this week.

May 30, 2012

Week 9


     The code only simulates the changing colors as it did last week, and will be illuminated separately. This code will be used to program a set of red, blue, and green LEDs with a set of white LEDs which will dilute the colors. This code will simulate daylight by changing the length of time that the colors cycle through to a full day.
     Because the code is finished, the group primarily worked with DIALux today. Trevor and John simulated the room so that the ceiling is implemented with skylights, and the noontime sun is shining through the holes. This will mimic the finalized room, as the lights will display the same colors and brightness as the sun.

DIALux simulation of the room with the walls oriented correctly with the sun at noontime.

     The simulated room has three windows: one visible on the back-left wall, and two unseen on the front-left wall. The other nine light spots in the room will be created with the light fixtures, but are simulated as skylights.
     We took screenshots of the room in half-hour increments over the course of a day, which displays the way that the light intensity will change. We will combine this simulation of intensity with the MATLAB simulation of color to create a lighting fixture which will change in both color and intensity.

An animated simulation of the room over the course of a day.

     The group will meet this week to finish the simulation and work on the final report and presentation.

May 23, 2012

Week 8

     Trevor, George, and John aided Gabrielle in creating the code over the week. It now progresses through the day with both color and intensity. It begins with a dim red, progresses to green and then daylight blue, then goes back down to green and red, and fades to black. This mimics the light patterns of daylight. The only problem with the code is that the blue has a grid on it, which Kate and Gabrielle are working to debug.

The MATLAB code now cycles through a typical day, but the blue has a grid on it.


     During the lab, Kate debugged the MATLAB code by changing the transparency of blue from 1.0 to 0.9999. For some reason, a 1.0 transparency caused a grid to appear on the screen. 

The modified MATLAB code cycles through a typical day and does not display any grids.

     During the lab, Trevor and John worked with DIALux to create a simulation of the room that will have the light implemented. They will modify the room so that it displays a sunlight simulation.

A DIALux simulation of the floorplan.

     The room will be simulated so that it displays a typical daylight situation, not the full daylight-simulating code.

A 3D DIALux simulation of the room. The walls are beige, though they look yellow in this rendering.

May 16, 2012

Week 7

     Today the group primarily focused on the codes. George and Kate analyzed and refined the given data into usable information, which Gabrielle converted into hexadecimal numbers. Gabrielle developed a code on MATLAB to simulate a display of the colors that will be created. John and Trevor worked with DIALux to model the room and predict where the light will hit for different areas of the room, based on Gabrielle's code.

The beginning stages of modeling the room in DIALux.

     The MATLAB code currently displays raw hexadecimal colors and does not utilize the intensity. The finished product will display the intensity and color values to model how the room will look with the light fixture implemented.

The MATLAB code currently cycles through the entire hexadecimal color spectrum.

     The group will continue to meet during the week to perfect the MATLAB code.

May 9, 2012

Week 6

     Today the group worked on developing combinations of red, green, and blue light to mimic different types of daylight. For example, red is at 100% intensity, green is at 100% intensity, and blue is at 98% intensity for high noon; and red is at 24% intensity, green is at 61% intensity, and blue is at 100% intensity for a clear blue sky. These percent values will be converted to hex code and outputted as a color value, which will be displayed by the LEDs.
     The group will receive help on MATLAB to work on outputting the correct data that will create a simulation displaying the intensity and color on the computer screen.

Trip to St. Francis Country House

Lights in the room created to distract and help the dementia patients.
 
     On Friday, May 4th, George and Kate visited St. Francis Country House. They explored the area that will implement the light, and took measurements of the current light values. The light values of the rooms were recorded so that their brightness could be seen numerically.

George taking a light measurement.

     There was a much higher value under the fluorescent lights than next to the wall-mounted light fixtures. These fixtures did not provide very much light, and mostly served as decoration. The project will focus on replacing the fluorescent lights with the color-changing lights.

On left: Fluorescent light at a low shutter speed. On right: Fluorescent light at a high shutter speed.

     The area that will implement the fixtures will be renovated so that there are different individual rooms and a common area. The light was measured in the bedrooms on each side of the hallway, as well as in the current common area.

Current hallway to common area with fluorescent lights on top and 4 watt bulbs on the walls.
     
     A good amount of data was taken at the House, and George and Kate learned about how the color changes will help the patients. There are many distractions, such as paintings of fish and motor activities on the walls to improve their disorder. The light fixtures will aid the sleeping patterns of the patients so that they have a more efficient circadian cycle, which results in a better disposition and a healthier outlook.

May 2, 2012

Week 5

     The group decided to shift focus primarily to sensing the light input and creating a light output. Raw data will be inputted into a MATLAB code that the group will write, and this code will output percent values for white, red, green, and blue LEDs. The code will communicate the intensity of the outside light to the LEDs to mimic the daylight.
     There is already raw data found for the light intensity for an average day. The wavelength and intensity are both recorded, so this code will put this into something that can be utilized. The light intensity in lux will correspond to how brightly the LEDs will shine, and the wavelength in nanometers will correspond to the color temperature, as dictated by the red, green, and blue LEDs. The group will experiment to find out the best numbers of each LED so the proportions mimic the color of daylight.
     The Kelvin temperatures in the raw data were converted to wavelengths in nanometers. Color temperature in Kelvin does not correspond to a color on the color spectrum, so Kate used the two main points to convert the other Kelvin temperatures to wavelengths, by creating an equation on Excel to relate the two. This filled in the rest of the chart so the wavelengths can be used to create a light spectrum with red, green, and blue.
     The group also began to code this data into MATLAB. The group needs to figure out how to display the results on the program, and an expert will aid in formatting this code correctly.
     The group will meet this weekend to visit the nursing home and to continue work on the code.

April 25, 2012

Week 4

     Today, the group completed initial research and figured out how DIALux works. Cooper Lighting lili was tested in the room simulation, because it uses LEDs and can function as direct and indirect light.
     The group also formulated ideas of adding UV light to the LEDs, because it creates Vitamin D, which will boost the health of the residents. Too much of it can be a carcinogen, but in small amounts, it has been proven to be healthy. A UV function is proposed that only operates for 15 minutes a day, in the middle of the day when the light is the greatest in the room.
     The group will visit St. Francis Country House on Friday, May 4th, to get a feel for the home and to take measurements of the rooms.

April 18, 2012

Week 3

     The group discovered solutions that have already been implemented, such as one in a German nursing home. This solution is too costly for the given budget, so this strategy may be used with cheaper or more environmentally-friendly materials, such as LED lights and reflectors. A light from IKEA which changes colors manually was examined, and it was decided that a similar light that changes automatically may be used.
     Trevor and John downloaded DIALux and began to learn how it works. This should help show the group where the light hits in a simulation of the full room.
     Drexel possesses a light meter, but they are very expensive. One will be needed to detect the daylight that enters the room. Because they are so expensive, the light may have to be programmed manually instead so that it follows a general daylight path, instead of what is actually outside.

April 11, 2012

Week 2

     Today, the advisor Greg Yeutter met with the group, and he explained DIALux in detail. He said that he would bring in a light with color-changing features so that the group would be able to examine it. The group decided to create a program that senses daylight and shows the colors with LED lights. A code will be designed that fades the red and blue lights with the white light so that it resembles daylight, and have a user interface that allows the white light to dim separately.

Week 1

     Today, the group met for the first time and decided to work on the LED project. The group wondered  how a sensor would work to simulate daylight, and chose to primarily focus on this part of the project. The project advisor, Greg Yeutter, introduced the group to the DIALux program that shows the light intensity in a room with these specific light fixtures.