As I have already mentioned in previous posts “my group have come up with the idea of intelligent street lights/lamp posts along roads to light up when cars are close by. This would be triggered by RFIDs on the cars/people so that when they pass under the lamp posts the RFID sensor will relay it to the lights to turn them on. Due to the varying speed (cars can go fast, people are slower…) different amounts of lamp posts would have to be turned on. So for cars for example 10 lamp posts would be turned on, then once it gets to the second to last lamp post the next 10 would be turned on. Then as it hits the second lamp post of the next set, the previous set of lamp posts would be turned off.”
Now this idea has changed slightly after thinking it over. The RFID sensor wouldn't be accurate enough as the RFID chip would have to literally pass right over the RFID sensor to pick it up, so first we tried using a passive infrared sensor but this would only let you know if there was any movement, not tell you how far away etc…
So we then tried using a PING ultrasound sensor which worked great as we could set a depth to turn on the LED. For example setting it so that when your hand is 5cm away from it, the LED would come on (in the images above). Great stuff! Now we have the concept working, we need to work on the broker side so that when someones is x distance away it can work out to turn on the current lamp post and 2 either side for example! The output gives us figures in cm and inches (shown in image below) but our max range is 20feet. This shouldnt be a problem for out prototype. The only issue is going to be power once we add a few more LEDs but the power source (battery/mains) will sort this.
The idea LED lights for this project if it were to be used in real life would be these recently unveiled LED lamp posts by Phillips. Made of durable materials that are easy to recycle and a LED module that is easy to replace needing little maintenance. Also carbon neutral - always a plus in todays world!