Cloud bad. Pi good.

This particular project isn’t unique in any way.  It’s almost more of a rant.

Originally, we didn’t really want a camera to check in our kid but that changed fairly quickly when we discovered he was fairly likely to scream happily while playing with his soft toys.  Climbing a flight of stairs to interrupt a happy baby really wasn’t working for us.

In a brief moment of time-poorness and low energy I ordered a Belkin NetCam HD off the internet.  I’ve used the Belkin WeMo kit before and figured it would Just Work(TM), I wouldn’t have to load an extra app on my phone and I generally wouldn’t have to think about it all that much.

And that was my mistake.  Cue the rant.

Before buying the Belkin camera I did a minimum of research.  One review said it could do local connections.  The camera was High Def.  Job done I figured.

How wrong I was.  I quickly discovered the following about the NetCam:

  1. It’s not the same App as for the rest of my WeMo devices.
  2. Joining the thing to your wireless is a nightmare.
  3. The first thing the NetCam does after finishing config is an update.  This update removes the local access, so now the only way to connect to the camera is across the cloud.
  4. Even on the lowest possible setting the cloud component smashes my admittedly fairly crap internet.
  5. The camera is horribly laggy.  It’s not unusual to go in to settle the kid, then 5 minutes later watch your own hand appear on the monitor.  This is probably related to the aforementioned internet, but man is it disconcerting.
  6. Only one device can connect at a time.
  7. The web app will time out after 30 minutes.

All this made me very sad, but caveat emptor absolutely applies.  I didn’t do the research.  More fool me.

So I’ve got a $140 lemon sucking up my internet connection and generally offering an annoying user experience.  I guess it’s back to the drawing board.

I had a look at the different types of commercial units around and the number of options is unsurprisingly staggering.  They go from the cheap with  fixed handset to the full on security system that give you a terminator like view of your kid, complete with heart beat and oxygen sensors.

I didn’t want that.  I just want a camera that I can connect to my phone/tablet/computer and check in.  And that’s how I ended up doing what I should have done in the first place.  I pulled a spare Raspberry Pi B+ out of a box, bought a Noir v2 night vision camera and made my own.

Turns out this is all pretty easy.  I did a quick google, picked a likely how to, installed the Camera Web Interface and walked off into the sunset, never to look back again.

Well, almost.  I couldn’t find any nice references to how to stick some IR lights on.  There’s a few nice little shields that people have done, but they all seem to use usb plugs in to the pi itself.  This seemed like a waste so I came up with my own, plugged straight into the GPIO pins and jammed into a commercial case.

Look at that.  500 words in before I actually get to some content.  Good one John.

When dealing with LED’s it’s important not to be too enthusiastic with the voltage.  I simulated my design a few different ways before I started committing hardware because blowing up expensive Super Bright IR LED’s seems stupid.

First, simulate one LED, one Resistor to try to get to optimum Ohms to Milliamps.

Fire seems like it would be bright, so, the one on the right?

According to the spec sheet for these LED’s, 20mA is the best place to be for current and light, so a 190 Ohm resistor is the right place to be.

But I’m aiming for 4, 6 or maybe even 8 LED’s here depending on how much extra brightness I need.  There must be a way I can use less components.

Don’t hold the lack of fire against it.

A little bit of tweaking and a single 50 Ohm resistor is about right to drive 4 LED’s.  They’re not perfectly on 20mA, but they’re close enough.

I did some further calculations but it’s probably a moot point.  These LED’s have a maximum voltage of 1.5V so I could probably even proceed without any resistors in place.

Now to make it all fit.

It was immediately apparent that the circuit board for the Noir camera was going to be a problem.  Fortunately, that was pretty easy to fix with some fresh holes drilled on my bench drill.  I found 7 mm was a snug fit for the camera lens and 5 mm was understandably perfect for the 5 mm LED’s.  I ended up adding a 32 Ohm resistor, just to make sure.

Last but not least, put a standard mount on the back so I can use any one of the dozen tripods and the like around home.

I tried superglue first, but ended up propping it up with hot glue.

The IR seems OK in the sub 1 Meter range at least.

Night Vision, sans Baby.

And what was the total cost?

$117!  Well, it beats out the WeMo.  Probably not a cheap solution though.  I guess it helped that I already had most of these components.

This whole project ended up only being a few hours work.  The Raspberry Pi realistically doesn’t take more than about 30 minutes and drilling, soldering and hot glue only took another 60.

So, the conclusion.  The video feed is still a bit laggy, especially when the boy is thrashing about a bit, but at least it doesn’t kill my internet connection for the privilege. There’s a phone app or I can run it in a browser.  Definitely an improvement from the Belkin.

John Spencer

I’m the hardware geek. I lean towards laser cutting, 3D printing, CNC routing and designing circuit boards.

You can find me on Github and Twitter.

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