Help or advice needed led lighting sequence

Using Arduino LEDs and Multiplexing
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Hi guys can anyone help me my plan is to hav a lighting controller for my stairs and driveway.

The idea is to have two reactive switches, one at the bottom of the stairs which will bring on the 12 led lights in turn starting from step 1 to step 13. And from the top of the stairs if the top switch is pressed the lights will switch on in order from step 13 to step 1.

If possible I would like them to come on in turn with an adjustable time delay before the next light to come on then stay on for a Minuit or so then all switch off

As for the driveway a very similar setup same circuit board and all

If anyone knows of any circuit board plans for this or any info would be most appreciated, I know it will be possible to be made all I need is diagrams

Cheers Mark

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12 single LEDs, or LED strips, or?

1 to 13 is 13 LEDs - does a selected stop not get an LED?

What do you have in mind for a "reactive switch"? Something mechanically operated (user presses a button, steps on a plate), a light beam that is broken, ultrasonic sensor, something else?

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Hi ther it will be more like led strip but if the output can drive an led it can drive a small relay to switch a larger load

The reactive switch would be mechanical as in like the light switch u get in a house but one that springs back (reactive)

So basically 12 outputs switch 1 to turn them on from output 1-12 and switch 2 to turn them on from 12-1

Cheers

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That is simple then. I have a little board with 3 TPIC6B595 shift registers that can control individual LEDs (with external current limit resistor) or 12V powered LED strips (strips are usually groups of 3 LEDs with a current limit resistor per group).

Reading one button press or the other is also easy. Buttons are wired from an input pin to Gnd, closing the button pulls the pin low and is used to start the timing sequence.

I can build one up & code it. PM me if interested in a quote for 1 or 2 sets.
Each output can sink 150mA continuously, so a long strip of 7-8 groups of LEDs per step can be used if all output are on at once.

LED strip examples here, as plain strips, in enclosures, etc. as one source example.
http://www.superbrightleds.com/cat/rigid-light-bars/

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I, too, am jumping on the "light my stairs" project bandwagon.

I know very little about Arduino so, please be patient with this noob.

I'd like to have a sensor and light at each step. My questions:
Is this possible with Arduino? If so, which board/s would work?
What would be best sensor to use? pressure? IR? light beam?...(cost is, of course, a factor)
When someone is on a step, and the light is activated, is it possible to have another step/s lit for another person? Eg; two people walking on the stairs, and each step is controlled individually.
Any ideas on what lights would be good to use? (L.E.D. of course, but, type? number per stair? optics? power supply?...)

Thanks, I look forward to reading your suggestions and ideas.

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Richrich:
I, too, am jumping on the "light my stairs" project bandwagon.

I know very little about Arduino so, please be patient with this noob.

I'd like to have a sensor and light at each step. My questions:
Is this possible with Arduino? If so, which board/s would work?
What would be best sensor to use? pressure? IR? light beam?...(cost is, of course, a factor)
When someone is on a step, and the light is activated, is it possible to have another step/s lit for another person? Eg; two people walking on the stairs, and each step is controlled individually.
Any ideas on what lights would be good to use? (L.E.D. of course, but, type? number per stair? optics? power supply?...)

Next time you go up or down a stairway try to imagine what it might be like if you could only see the step you're on, and the next one - it would be almost impossible to use the stairs safely at any reasonable speed. Your idea is easy to implement - running an LED or relay from a switch is simple, it's one of the example codes. Use of a shift register is in a lot of beginner kits too.

http://arduino.cc/en/Tutorial/Debounce (how to read a momentary push button - it's called 'momentary' BTW, all switches are 'reactive' )

http://arduino.cc/en/Tutorial/BarGraph (controlling lots of LEDs)

The answers to your questions about numbers of lights and such will affect your circuit design. As mentioned above, every circuit is limited to a certain amp draw, above which the components will usually melt or fail in some other way. So, you kinda have to design your lighting, figure out how many LEDs and what type, then you can pick your control devices. LED strips add up fast! Each LED usually pulls 20 milli-amps, 60 per segment - so three segments is the limit to how much the Arduino can control by itself, and that's also the limit of each pin on the shift register mentioned above. However, three segments of white LED strip is pretty darn bright, more than enough to light a stair step. One segment on each side would probably be bright enough. You are going to need to decide what to use though - we can't see your steps.

I did a video about LEDs a while back - I explain the drawbacks of the strips and why you might want to hand-wire your LEDs. The main issue is the strips need to run on 12V.

This shows some different types of LEDs, how to wire them up, how to solder them, how to design your circuits and so on.

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Awesome.
Thank you for the info.

In my description, I talked about one sensor/light per step, and I understand your comment about this set up in the dark and safety concerns. I figured that I'd play around with that in the sketch and just wanted to keep my questions as simple as I could.

Since I have no experience with the different trigger methods out there, I have no idea what might work best for my application and the use of Arduino.

As for the type of LED, my thought was to find the Arduino board most suited for my application and then decide on the LED type. That way, I could decide if the board would give me what I wanted or if I'd need to design some sort of relay set-up.

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Well, turning on lights is so simple that ANY Arduino can do it - you can use a micro or nano even. The limitation is in the number of pins - any Arduino should have enough code space and memory to comfortably manage 40 to 50 lights responding to a number of different inputs. With shift registers and other devices, you can control multiple lights from a single pin on the Arduino, so even the pin count is not much of a limitation. So, I would take the opposite approach - figure out the electrical properties of the system first - how many lights, how many switches, what are the inputs, how much power do we need, etc. Then, you will have a better idea of what types of Arduino would meet your needs. When you have no requirements, it's kinda hard to do a gap analysis on hardware.

So, I would go ahead and draw up your schematic from an electrical perspective, showing only the lights, not the control mechanism (which will be a relay or transistor) - so we can get an idea of how many control points and inputs need to exist, and what the power requirements might be. Post that drawing here and field suggestions on how to control it.

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Hello,

It's been quite a while since I've been able to work on this project and now that I have, I'm stumped.

I'm using a Mega 2560, 2 PIR sensors, and 24 white 3.0-3.2v LEDs (model# IL152 from microtivity.com)

My first problem: using a simple "blink LED" sketch I can easily get a single LED to blink with a decent brightness. When I try to add another LED to the circuit they only blink very dimly. I've tried using different resistor values but nothing I've tried produces anything more than "barely lit". I don't want to keep "throwing resistors at it" hoping I stumble upon a working combination. What value should I be using? Is there a specific way to wire these components?

Second problem: Assuming that I was simply missing the right resistor/LED combination, I went ahead and wired up 12 LEDs and the two PIRs on my breadboard. I thought I could at least play around with the sketch lighting up single LEDs in a sequence and adjust the delay, timing, etc.

Using two sketches I found on the web, I am unable to get anything to work.
I've played around with a PIR activating a single LED and believe that I have everything wired correctly. Not having a schematic to go with the sketches leaves me making "educated guesses" as to where everything should go. Obviously, I've done something wrong.

One sketch I downloaded is from here: /* Arduino Stair Poject * With Infred Sensor And LED Lights On Either Sides Of - Pastebin.com

Anyone have any ideas for me?

Thanks!

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Richrich:
Not having a schematic to go with the sketches leaves me making "educated guesses" as to where everything should go.

Yeah, probably shouldn't do that unless you have prior electronics experience. Don't ask me to do it either. Please post pictures or something so we can see what you are working with. We don't know what you mean by adding more LEDs, you gotta at least describe the wiring.

Have you seen this?

11

It's been a while since I dug into this, but I've dusted off my Arduino with the goal to get this project finished.

I'll recap my project goal and state my question to y'all.

Using a PIR at the top and bottom of my staircase, and two LEDs at each step (total of 24 LEDs), I want the PIR to trigger a sequential lighting of each step.

My question is about the hardware; I know that my Arduino can't supply the necessary voltage to power all of the LEDs. What do I need to accomplish this?

I've read where some people use some sort of IC that is no longer being produced.

I've read about the use of a shift register as a possible option, but have been unable to find out if (or how) to use one in this application.

I've also read where a transistor and/or MOSFET could be used, but I am a loss as to how go about doing this.

What would the collective wisdom here recommend?

Thank you in advance.

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Richrich:
Using a PIR at the top and bottom of my staircase,

Like one of these?

Beaut little devices, very suitable for this application.

Do specify exactly what LEDs you presently propose to use.

TPIC6B595s (or TPIC6A595s) may be suitable.

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Paul -

The hardware I have consists of a Mega 2560, 2 PIR sensors (just like what's in the picture you provided), and 24 white 3.0-3.2v LEDs (model# IL152 from microtivity.com).

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Oh, that advert is classic!

Regular Price: $0.00
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You Save: $**-**6.99 (100%)

That aside, it gives no useful information on the LEDs - or the resistors - but we must presume that the LEDs will be rated at 20mA. If we know what value the resistors are, we can figure for what voltage they were intended (generally speaking, 100 Ohms for a 5 V supply, 470 Ohms for 12 V).

These would suit very well with a TPIC6B595 and a Pro Mini.

15

Paul -

Thank you for your reply.

Are you suggesting that I NOT use the Arduino board that I currently have?

After a little Googling, and assuming that a shift register (as you recommended) is the best course of action, wouldn't a STP16C596 be a better option?

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Richrich:
Are you suggesting that I NOT use the Arduino board that I currently have?

Pro Minis are dirt cheap. And small. The Mega 2560 seems like wild overkill. Better used where it is needed.

Richrich:
After a little Googling, and assuming that a shift register (as you recommended) is the best course of action, wouldn't a STP16C596 be a better option?

Maybe. Can you get one? The datasheet says it is obsolete for some reason.

I recommend things that are available. (Easily available.)

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That's what I suggested back in reply #3.
TPIC6B595, TPIC6C595

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