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$30 Homebrew Automated Blinds Opener (2024)

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Re: $30 Homebrew Automated Blinds Opener (2024)

#4
What are the child safety considerations to be careful of, with blinds, and with openers?

(I recall seeing warning stickers and design changes on ordinary miniblinds. I suspect that one of the changes involved having multiple pull cords be separate and loose, rather than a fastened together or a single looped cord. But I'd guess that's not the only safety design decision.)

Re: $30 Homebrew Automated Blinds Opener (2024)

#5
post #2

Would measuring motor current be a better way to determine torque? Not an expert but seems like you could sense voltage across a fairly small shunt to do it.

That's how we did it when I worked on a gate-arm/access control system. I'd monitor current and if a spike occurred I'd back the arm up because it likely hit something.

Re: $30 Homebrew Automated Blinds Opener (2024)

#6
post #2

Would measuring motor current be a better way to determine torque? Not an expert but seems like you could sense voltage across a fairly small shunt to do it.

Motor current is a workable, but generally unsatisfactory, proxy for torque when using heavily geared motors. Far better to measure output torque directly if you can, which is what's being done here using what is essentially a series elastic mechanism (itself a very common way of implementing torque sensing).

To elaborate more, current sensing is only "better" in an ease-of-implementation sense, in that a lot of motor drivers already have current sensing built in/easily added. For some applications this is good-enough, but in terms of estimating "real number" torque from current, it can take a lot of work to characterize for geared motors.

Re: $30 Homebrew Automated Blinds Opener (2024)

#7
Fwiw automated blinds in the bedroom are a 100% no brainer benefit. It's wonderful and better than an alarm clock with 0 mental load (set the times to open close across the week once and then never think about them again, you can keep the weekend manual if you like).

As in a lot of home automation actually makes things worse. Replacing a convenient light switch with an app? 100% terrible idea and actually makes things inconvenient, don't automate those.

But the blinds, specifically those in your bedroom? Do it! One of those life hacks that's really not that expensive and makes your life better with 0 cognitive load after initial setup.

Re: $30 Homebrew Automated Blinds Opener (2024)

#8
I just want to share that these are by far the best home automation you can have. I love my smart lights, hacked together smart humidifier, smart fans (the vornado dc fans with outlet switches), intake air pump, and air quality monitoring.

But nothing has the quality of life impact of smart blinds. It’s the best, and probably only, way to reliably keep your sleep schedule in sync. Smart lightbulbs - four of the brightest you can buy - are nothing compared to a window on a cloudy day.

Re: $30 Homebrew Automated Blinds Opener (2024)

#9
post #4

What are the child safety considerations to be careful of, with blinds, and with openers? (I recall seeing warning stickers and design changes on ordinary miniblinds. I suspect that one of the changes involved having multiple pull cords be separate and loose, rather than a fastened together or a single looped cord. But I'd guess that's not the only safety design decision.)

I think the principle two things are “they can’t pull it off the wall and onto themselves” and “they can’t hang themselves”.

With automatic openers you add “they can’t get snarled up/lose a finger in the mechanism” and “they can’t electrocute themselves”.

I went extremely belt and braces with our blind opener - but it is toddler proof. Attached the lower end of the cord to the ceiling, attached a pulley that hangs on the cord, hung a 1kg weight from it, and used a solenoid from a broken linktap valve to pull a pin that allows the weight to fall and pull the cord.

Even with the blinds open the whole assemblage is entirely out of her reach, and it goes for the opposite effect to the poster’s implementation - blinds slam open in about half a second with a quiet whirr, as I prefer a jarring wakeup, and my wife would sleep through Armageddon. Reset is manual, but that’s fine, closing them is an optional and trivial activity.

Re: $30 Homebrew Automated Blinds Opener (2024)

#10
post #4

What are the child safety considerations to be careful of, with blinds, and with openers? (I recall seeing warning stickers and design changes on ordinary miniblinds. I suspect that one of the changes involved having multiple pull cords be separate and loose, rather than a fastened together or a single looped cord. But I'd guess that's not the only safety design decision.)

What are the safety considerations of smart blinds opening up a bedroom at inopportune moments, such as children playing outside while you're having sex or changing clothes?

Is there a lockout mode for "I/we are not decent" or do the blinds just sort of majestically reveal the bedroom to your backyard/parking lot observers like curtains opening on a feature film?

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