Tag Archives: lighting

Osram Develops LED Beam Array Smart Headlamps That Can Analyze Road And Traffic

After over three years of research and field demos, a prototype of Osram’s EVIYOS smart, controllable, high resolution LED automotive headlamp was introduced at the International Symposium on Automotive Lighting earlier this year in Darmstadt, Germany. This smart LED headlamp is able to control its 1,024 LED “pixels” individually. The basic component of the EVIYOS combines an LED chip with electronics to provide on/off and dimming control for each pixel within the LED module.

Smart Beam Array LED Headlamp By Osram
Smart beam array LED headlamp by Osram

The only 4×4 mm module is capable of delivering about 3,000 lumens when fully activated. The brightness is much greater than the 1,400 lumens of the typical LED automotive headlamp modules. The required circuits to control this module is already connected to the headlamp and it includes an interface for connecting directly to the vehicle electronics. The truly “smart” aspect of this invention is, the system can continuously analyze factors such as the car velocity, road curvature, and distance from other vehicles on the road, including oncoming traffic. Then it makes adjustments to the light emitted from the vehicle’s headlamps accordingly.

For instance, a wider beam would be provided for high crowding areas to illuminate the road ahead and also the sidewalks. Having individual pixel control capability, the headlamp can adjust the light output very precisely. Hence, it can provide better visibility for other drivers sharing the road by dimming the specific pixels that would otherwise be causing glare, while still illuminating the road nicely.

As it is scheduled to launch in 2020, Osram is looking forward to offering a separate family of modules targeting lighting applications for which individual control of light pixels would be useful. When asked about potential future markets for EVIYOS technology, Osram responded,

with the increasing need for adaptive forward lighting and glare-free headlamps, a dynamically controlled matrix light source provides additional benefit for forwarding lighting and certain interior lighting applications in a vehicle.

So, with the formal launch over two years away, only time will tell if this new technology by Osram can cure the nightmare of night driving.

Temperature Controlled Stair lights With Raspberry Pi

Ever wished to know the temperature on your way to breakfast after waking up in the morning? Now you can find it out in a fascinating way as Lorraine Underwood at The MagPi magazine designed a temperature controlled colorful stair lights system with raspberry pi. In this tutorial, we’re going to discuss that project.

Temperature Controlled Stair Lights
Temperature Controlled Stair Lights

Required Parts

  • Strip of 50 neopixels
  • A 5V power source for the lights
  • 2 x terminal blocks
  • 2 x male to female jumper cables
  • A raspberry pi zero with SD card with Raspian installed
  • Power supply for the Pi zero (temporary)

 

Make sure that the raspberry pi power supply gives exactly 5 volts and is capable of outputting 2.5A current.

Make The Circuit

At first, examine your LED strip and find out which pin is what. Connect two wires to GND, one wire to Din, and one wire to +5V pin. Now, connect the 5V pin to the “+” terminal of the female jack and GND pin to the “-” terminal. Tighten the screws of the terminal block to ensure that the wires are connected properly.

Connect the Din and GND pin of the LEDstrip to the GPIO 18 and GND of the Raspberry Pi respectively, using the male-to-female jumper wires. Please note that Broadcom numbering (BCM) is used in this tutorial, not the physical numbering. It will look like below after making the connections:

Connecting Wires To The LED Strip
Connecting Wires To The LED Strip

Set Up The Weather API

You need to set up a weather API in order to get the outside temperature in your area. In this tutorial, forecast.io is used as they allow you to make 1000 queries per day free of cost. Go to forecast.io and select Developer option. Then, click sign up to create a developer account and provide your email address. A secret key will be sent to that address. Store it securely as you’ll need in the next step.

Prepare The Raspberry Pi

At first, you need to install the Adafruit NeoPixel library rpi_ws281x. Go here and follow the instructions to install the required files on your raspberry pi. Once installed, navigate to the examples folder, run any script you wish, and check if the LED strip is functioning properly.

Now, save the below script as stair_lights.py in the Raspberry Pi:

#!/usr/bin/python3
from urllib.request import urlopen
import json
import time
from neopixel import *

apikey="get_your_own_key" # get a key from https://developer.forecast.io/register
# Latitude & longitude - current values are Lancaster University
lati="54.005546"
longi="-2.784876"

LED_COUNT = 50 # Number of LED pixels.
LED_PIN = 18 # GPIO pin connected to the pixels (must support PWM!).
LED_FREQ_HZ = 800000 # LED signal frequency in hertz (usually 800khz)
LED_DMA = 5 # DMA channel to use for generating signal (try 5)
LED_BRIGHTNESS = 8 # Set to 0 for darkest and 255 for brightest
LED_INVERT = False # True to invert the signal (when using NPN transistor level shift)

def color(strip, color, start, end): 
 for i in range(start, end+1):
 strip.setPixelColor(i, color)
 strip.show() 
 
strip = Adafruit_NeoPixel(LED_COUNT, LED_PIN, LED_FREQ_HZ, LED_DMA, LED_INVERT, LED_BRIGHTNESS)
strip.begin()

count = 0
try:
 while True: 
 #get the data from the api website
 url="https://api.forecast.io/forecast/"+apikey+"/"+lati+","+longi+"?units=si"
 meteo=urlopen(url).read()
 meteo = meteo.decode('utf-8')
 weather = json.loads(meteo)

currentTemp = weather['currently']['temperature']

#negative number will always be on 
 color(strip, Color(0, 0, 255), 0,7) # Blue
 
 #what's the temp?
 if currentTemp > 0:
 color(strip, Color(75, 75, 255), 8, 15) # light Blue
 if currentTemp > 5:
 color(strip, Color(0, 255, 0), 16, 23) # dark Green
 if currentTemp > 10:
 color(strip, Color(75, 255, 75), 24, 31) # light Green
 if currentTemp > 15:
 color(strip, Color(255, 100, 0), 32, 39) # yellow 
 elif currentTemp > 20:
 color(strip, Color(255, 50, 0), 40, 47) #orange 
 elif currentTemp > 25:
 color(strip, Color(255, 0, 0), 48, 50) # Red 
 #check every 5 minutes (change to crontab)
 time.sleep(300)
 
except KeyboardInterrupt:
 print("Exit")
 color(strip, Color(0,0,0), 0, 49)

Enter your own secret key in the apikey field on the 7th line. Also, replace the longitude and latitude values on line 9 and 10 with the coordinates of your area. Now save the file and you are almost done.

To start the script automatically after each reboot and check the outside temperature every five minutes, set up a cron task by entering the following command:

sudoE crontab -e

A file will be opened and add the following lines at the end of the file:

*/5 * * * * /usr/bin/python3 /home/pi/stair_lights.py
@reboot /usr/bin/python3 /home/pi/stair_lights.py

Save the file and exit.

The Color Scheme

The following table shows which color represents which temperature range. You can modify the script to change the current color scheme.

Temperature (°C) Lights (Nos) Color
 0 – 4  9 – 16 Light Blue
 5 – 9 17 – 24 Dark Green
 10 – 14 25 – 32 Light Green
 15 – 19 33 – 40 Yellow
 19 – 24  41 – 48 Orange
 25+  48 – 50 Red