Roll your own controls

[erasei]

After writing this post, I realize I get a little 'far out' in some of my questions or thoughts. I don't know if there is a 'dude you're too weird for us' section in this forum, but mods can feel free to move this post if they so choose.



Do any of you guys roll your own control interface for your own projects that are PC based? Meaning, instead of using the PC to interface via x10/UPB/Insteon/others do you guys run any custom-made motor/servo/sensor controls?

I'm mostly interested in the interface you use between the device and the PC. There are serial based servo controllers for PCs, they are about $25 and can control up to 8 digital devices or i think 2 or 4 analog devices depending on the model. What about remote sensors communication back over Wifi, RF, or even something lower level. Some pretty sophisticated components are available ready for the DIYer to integrate at relatively low cost.

I have several projects in mind that are either cost prohibitive to buy a pre-made solution or I just can't find a solution for... and I just enjoy DIY electronics projects. Ideally they would all tie back to the PC so that I can be alerted via the home automation system.

Project #1 The AI Humidor:
Phase 1: Humidor temp and humidity sensors. Would probably need to be battery powered since I don't want to drill into my humidor. Would only need to send back data every so often, like every 6 hours or so at the most. Needs to be really small, which is why I can't use one of the pre-made sensors.

Phase 2: Add a small actuator of some type that is strong enough to open the lid of the humidor. Cigars off-gas as they age and you need to crack the lid to let those gases escape about once a week at least. During the summer time that isn't a problem as I'm in the 'dor once a day anyway. During the winter months though, my 'dor sets untouched for months at a time. (Except the once a week i have to remember to go check it out, let it off-gas, adjust fluid levels, etc)

Phase 3: Build a distilled water and glycol tank that will automatically adjust fluid levels based on current interior conditions as reported by the sensors. This might be as simple as a gravity fed system, but that might over-hydrate the humidor and take the humidity level too high. If so, then a computer controlled dispensing system will be required. I'm guessing a micro version of a sprinkler system would work. A small electronic water valve.


Project #2 Manual curtain get automatic: Pull a small rope. I have one set of windows in my house where I can't install a motorized curtain. It's one of those curtains where you kind of gather the middle to one side. I think a small continuous rotation servo could wind the cord around a shaft that would open the curtain. This would be easy at first, but as the cord wound around the shaft it would in essence reduce the gearing of pull vs motor rotation, which would make it harder to pull the farther along into the pull. Maybe just doing a double wrap around the shaft and then dropping the cord down the wall would work. Basically work the same way without the cord building up on the shaft.


Project #3 Close the window: A 2-3' linear motion. All of the windows in my house are the horizontal type. Instead of lifting up, they slide to the side. Here in the Northwest US nobody really has Air Conditioning in the houses, so our windows stay open most of the summer. Many many nights get really cool here though, even in the summer and we wake up freezing at 2am and have to get out of bed and close all the windows. It would be REALLY helpful to have this as just another part of the automated home.

This is a complicated project though.. mainly due to the weight of the windows (probably 20-30 lbs of push force required) and the distance of travel required (2-3 feet). My best guess so far is a powerful DC motor that uses a screw drive to push the window. With a gear offset you could get by with a reasonably powerful motor without spending stupid amounts on 5 hp DC motors. Speed isn't critical so a 10 second per 6 inch travel time is acceptable. There are complications with opening the window.. would the system need a clutch of some sort to disengage the gears when someone grabbed a window and yanked it open in the afternoon? You could mount a small button switch beside the window for electric control (this would also be good for the young and the old [neither of which we have atm]).


Some of my other projects that are less complicated and pretty easy to do..

* Cat waterer, pretty easy, just basically another sprinkler installation on a small scale, with some type of "off" control.. like a float or something such.

* Turn the main tv to a specific input (front door camera) when the door bell rings. A basic reed switch as the door bell that uses an x10 power flash to relay back to the PC which then sends the right IR code to the IR Blaster on the TV (sadly my plasma doesn't have rs232 control)


I guess that's it.. I'm curious to see what projects similar to these that other users have done. Sorry if I got a little long winded.

 

[TonyNo]

You have some interesting projects queued up!

Project 1, Phase 1: Do you really want a battery in there? If it leaks, it would seem to be pretty bad for the cigars. You may be better off with drilling a small hole for wires and sealing it. Take a look at the 1-wire temp/humidity sensor here.

Project 1, Phase 2: Seems like a standard servo would be perfect for this, but I don't know how hard it is to open your humidor. I have used this unit from Pololu before for a project of mine.

Project 1, Phase 3: Get a gel canister!

Project 2: Seems like you have a good plan already.

Project 3: If you use a clutch, the pitch of the screw would need to be fairly steep so that you could open or close it manually. You also need to worry about the system being able to tell if someone or something is in the way and to open if so (like a garage door).

 

[beelzerob]

Ya, I'd be surprised if you can find a system for the windows that is workable, safe, and aesthetically pleasing enough to pass the WAF (assuming it applies to you).

I'd think it might be better to make some kind of a system that pulls in outside air and distributes it through the house (do you have central air?), which could then be turned off when it gets cool enough.

 

[erasei]

You have some interesting projects queued up!

Project 1, Phase 1: Do you really want a battery in there? If it leaks, it would seem to be pretty bad for the cigars. You may be better off with drilling a small hole for wires and sealing it. Take a look at the 1-wire temp/humidity sensor here.

Project 1, Phase 2: Seems like a standard servo would be perfect for this, but I don't know how hard it is to open your humidor. I have used this unit from Pololu before for a project of mine.

Project 1, Phase 3: Get a gel canister!

Project 2: Seems like you have a good plan already.

Project 3: If you use a clutch, the pitch of the screw would need to be fairly steep so that you could open or close it manually. You also need to worry about the system being able to tell if someone or something is in the way and to open if so (like a garage door).

Yeah, battery leaking would be really bad on the cigars, but drilling into my high dollar humidor is almost as unpleasant, and its a 'sure thing' and the leaking battery is 'might happen someday' thing. I figured I would investigate sealed batteries to see if I could use one of those. I might have to bite the bullet and drill it though. It's amusing.. I'm willing to hack up my window frame to install a DIY closing mechanism in my half million dollar house but I'm not willing to drill into my few-hundred dollar humidor! hehe

I like polulu, I was actually checking out this unit: http://www.pololu.com/catalog/product/727 which is basically the same but can control up to 8 servos, and is only a few dollars more.

Gel canisters are for women and children! LOL. If I'm going to do this amount of work (and I am!) i want it to pay for itself (at least in theory). Having to replace the gel canisters every few months would add to the expense pretty heavily, compared to distilled water and glycol.

The window closer is definitely going to be the hard one to do right. Thanks for the feedback, I'll see what I can come up with.

 

[erasei]

Ya, I'd be surprised if you can find a system for the windows that is workable, safe, and aesthetically pleasing enough to pass the WAF (assuming it applies to you).

I'd think it might be better to make some kind of a system that pulls in outside air and distributes it through the house (do you have central air?), which could then be turned off when it gets cool enough.

Oh I definitely have to consider the WAF, but thankfully my Acceptance Factor is pretty high. She's not as avid a geek as I am, but she is definitely a geek. For 'private' areas of the house its pretty much anything-goes.. I really only have to 'reel it in' when its in the entertaining areas.. aka, when her friends might see how geeky her hubby really is. hehe.

No AC, but we do have central heating. The house is a split level, so the downstairs area always stays really cool. Yesterday it was 95 outside and probably mid-70s down there. I was actually thinking of a way to pull that cool air out of there and up into the rest of the house using the existing duct work. It would certainly be easier to control than the windows.

 

[BraveSirRobbin]

You might want to look into some of my How-To's for ideas.

I would look into a vehicle window washer pump and a float switch. Search under "fountain" and my handle for a cheap float switch.

All Electronics has various solenoids that you might be able to use to lift the lids of your cigar cases.

Will 'Wi-Fi' penetrate into your humidor?

 

[erasei]

You might want to look into some of my How-To's for ideas.

I would look into a vehicle window washer pump and a float switch. Search under "fountain" and my handle for a cheap float switch.

All Electronics has various solenoids that you might be able to use to lift the lids of your cigar cases.

Will 'Wi-Fi' penetrate into your humidor?

I've looked over the HowTos but I'll go back and do more indepth reading. Thanks for the pointer in that direction.

Those would probably work well. I really only need about an inch of travel, then just hold it for a few minutes, and release.

I haven't tested it but i don't see why not. My wifi range is really good throughout the house, it will reach anywhere on my property that I've tried so far, which is through several walls and floors.

 

[TonyNo]

I really only need about an inch of travel, then just hold it for a few minutes, and release

The few-minute hold time may kill the solenoid idea.

 

[beelzerob]

If you have central heating, do you have cold air return registers also? If so, then can't you just turn the fan on only? That will take in air from every part of the house, mix it together, and then return it to the house...so it will mix your cooler downstairs air with the upstairs.

If that's the case, then you could look at motorized/controlled dampers to selectively close off an area of the house from getting air...for instance, pull cold air from downstairs but only blow air upstairs and get a cycle going that way.

You could then also add an extension of your ducting to an outside air source for pulling in cool air instead of having windows open (kind of like moving the "fresh" air in the car vs. recycled air). Of course, all safety cavaets apply to anything I've said...

 

[pete]

You could then also add an extension of your ducting to an outside air source for pulling in cool air instead of having windows open (kind of like moving the "fresh" air in the car vs. recycled air). Of course, all safety cavaets apply to anything I've said...

this is what is done in alot of office buildings/commercial HVAC (some municipalities require it as part of an energy code) . . it's called an economizer (or economizer mode) . .

the " extension of your ducting " needs to be on the return side, and a couple of motorized dampers to isolate which one (indoor or outdoor air) is active . .

depending on how new and 'air-tight' your house is you may need a relief damper to the outside as well . .

Pete C

 

[beelzerob]

(some municipalities require it as part of an energy code) . . it's called an economizer (or economizer mode) . .

That's shocking! Shocking at how smart it is, anyway. Our last house in Arizona we frequently had to run the AC even though it was very cool outside...but with no way to pull that air in. Our new house we have a whole-house fan, which does absolutely fantastic for replacing the inside hot air with cool outside air. There are some dangers and "gotchas" to it, though, so something like what you describe, where it's part of your central air system, would be safer and more efficient I'd think. And then you could control it with a simple aprilaire type controller.

 

[erasei]

Honestly I don't know if we have just a fan. We just bought the house May 1 and I'm already in the middle of a bathroom remodel.. changing the downstairs half bath into a full bath, complete with having to jackhammer a drain trench across the floor.. wheee.

Great ideas though. It would make a ton of sense for us to do both of those as soon as possible. It may get to be 95 a few days out of the year during the day here, but it drops right back into the low 70s and 60s at night where the outside temp drops a lot faster than the inside temp does, so having that outside-to-inside air exchanger would be awesome.

 

[pete]

back to the topic of rolling your own . .

never got past the 'hey, would this work' stage, but was thinking of trying to use stepper motors to control my verticle blinds and/or replacing the crank handle of my casement windows ?. . never messed with them before so I don't know how much torque you can get out of them tough. .