Commercially available motorized window blinds are a nice high-end touch for today’s automated home, but they tend to command a premium price. Seems silly to charge so much for what amounts to a gear motor and controller, which is why [James Wilcox] took matters into his own hands and came up with this simple and cheap wireless blind control.
[James] started his project the sensible way, with a thorough analysis of the problem. Once COTS alternatives were eliminated – six windows would have been $1200 – he came up with a list of deliverables, including tilting to pre-determined positions, tilt-syncing across multiple windows, and long battery life. The hardware in the head rail of each blind ended up being a Moteino on a custom PCB for the drivers, a $2 stepper motor, and a four-AA battery pack. The Moteino in one blind talks to a BeagleBone Black over USB and wirelessly to the other windows for coordinated control. As for battery life, [James] capitalized on the Moteino’s low-power Listen Mode to reduce the current draw by about three orders of magnitude, which should equate to a few years between battery changes. And he did it all for only about $40 a window.
Window blinds seem to be a tempting target for hacking, whether it’s motorizing regular blinds or interfacing commercial motorized units into a home automation system. We like how compact this build is, and wonder if it could be offered as an aftermarket add-on for manual blinds.
26 thoughts on “Compact Controllers Automate Window Blinds”
I’m skeptical of the “years” battery charge claim. Also, I am curious what brand of blinds are being used. The ones I have are pretty heavy and I suspect would probably require beefier components.
Indeed. Even if nothing was connected to those batteries, they’d be drained from self-discharge after roughly 5 years.
Years of battery life, if you never use the stepper motors.
I wonder if a small phone charger might be better suited.
For really low power maybe a relay could turn off the primary unless the stepper is being used. Perhaps powering the board from a super capacitor topping it up momentarily now and again and then disconnecting the primary until it’s needed again.
I think I might end up using a second capacitor probably something like a 2200uF electrolytic as a reserve tank to actuate the relay without browning out the controller. Just enough to quickly click it on and back off a second or so later.
supercaps have a horribly high self-discharge. You’re better off with a couple of LiFePO4 cells and float-charging them occasionally.
what about a small solar cell since it’s on a window anyway.
i mean, not a solar cell alone but with proper batteries as you suggested.
and as i look down the thread “RP” already had this idea.
Something like this is great, but it is tilt only and won’t raise the blinds. There aren’t a lot of COTS solutions that are good quality, and that is one reason why it costs so much to an end user. If you think about ROI, possibly lighting and HVAC energy savings, or the big ROI by protecting your flooring and furnishings from the sun, then the cost starts to make sense for certain windows. But just like other aspects of home automation, only gaining push button control of something isn’t going do the job for ROI, automating it to track the sun, dimming lights in response to natural light, or to open blinds to allow solar heat gain is where the motorized blinds/shades start paying for themselves.
You should shop around more.
I can think of 4 large companies that make automatic shade controllers, and a UL standard for them as well.
I am aware of all of the options from the market leaders, I just wouldn’t consider them cheap-off-the shelf since they sell to window covering fabricators. The basics of motorizing window coverings are simple, but then you try to do it yourself and you discover there are many different tube profiles, adapters, motors and lift capacities, etc. I wouldn’t have any problem buying or making the components to motorize, and you may not have trouble either, but 99% of the people would. That is why any DIY attempts like this usually involve servo motors, and that the servo solutions launched a bunch of Kickstarter projects that wouldn’t have the power or speed to work on the majority of windows. I agree, stick with the large companies tubular motors and components and you’ll end up with a better product. Although I always applaud someone making their own solution for themselves, just don’t take it to KS.
It’s a window. Use AA NiCds and put a solar panel facing outward against the glass.
Sometimes the obvious just isn’t so obvious ;)
If my sons toys (the damn noisy ones with out an on off switch are anything to go by…. A couple of years probably isn’t inconceivable
You can get semi-flexible panels/cells. If you don’t mind dark blinds you could mount them on the slats
I wonder if it would be practical to get a small solar charger and put it somewhere near the top of the window. That way you could potentially recharge a power source up over the course of each day.
Also if you do read his design notes you’ll see where the “years of battery life” comes from, his measurements , calculations and reasoning behind the claim.
The Vstore cap can be farads if you have enough time to wait.
It’s cool, that’s the ROI which can’t be matched!
Even dumber and cheaper approach; use a solar panel external usb power bank. They cost about 10usd and do all the solar charging and provide a nice smooth 5v, 1A. Near a window they recharge ~2-3 Wh per day which can be enough for few blind changes in a day.
You guys seemed to have forgotten what the purpose of hacking is all about : doing something that is interesting for the individual. Sure, at $200 a piece, a COTS solution is pricey, and if you take into account the time spent developing & implementing this $40 solution, it might just cut even when considering 6 windows.
But, he learnt, and he enjoyed himself. He could have kept this whole thing to himself and saved himself the grief from all the negative comments.
On the other, the comments about solar charging are very positive. I for one am glad to see this sort of project being posted, even though I’ll probably personally never use it, or any part of it.
I will use this project and I commend the guy for posting it. I agree with some of the feedback, the positive feedback. Harnessing the power of china, the solar battery backup pack seems to me a logical and cheaper (than duracell!) method of powering it and I’ll be doing that.
I did wonder why if going to the effort of rolling your own PCB you didn’t roll your own arduino too ?
Personally to save cost I’m going to go the route of a standard arduino, the stepper with controller and a 433mhz tx/rx setup. All in shipped from china plus the battery pack this is less than $15 (go price it up) and some changes to the code.
I take my hat off to you sir.
Did you ever complete your build from China?
batteries? solar cells?
just wire it into mains electricity, it’s a window its not going anywhere. pretty much the definition of a fixed appliance.
I looked into getting new, automated blinds, but was given a quote of over $3,100 for just a couple of windows. I’d really like to at least automate my living room window blinds though, but that cost is way too high.
The best reason for doing something is to have no reason.
HAD had a similar article a couple of years ago with a guy who was using cheapo servos for the same thing … I think the whole mechanism side was a ton cheaper:
I don’t get it, why people always have the need to make things automated?
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