Occupancy Sensing

[hucker]

I've been playing around with interior motion sensors and occupancy sensing. The more I think about it the less I want to do it :blink:

At first it seems really cool to be able to turn lights on, only at night, when certain motions are detected. That I can do but man does it start to get complicated.

For example we have 4 bedrooms upstairs and a long hallway with a bathroom off of it. We have little kids, so it would be nice if they came out of thier rooms and motion was detected that the hall light and bathroom light would turn on dim.

1) What times should this happen.
2) What should we do about the current state of the lights.
3) Should they auto turn off after a period of inactivity.

Now add to this that there are stairs at the end of the hall...

4) Do I need to turn on the stair lights too? Timer?

If I do try to time things then certainly I need to keep watching the motion sensor so I don't turn things off when people are around... sort of a watchdog thing.

Who is doing this stuff? How complex did you have to get to make it useful...

The things I have to track occupancy are door sensors, motion sensors, lights turning on/off, alarm system state and MAYBE PC screen saver state. I can tell when the phones are off the hook too but I can't see how I could use that to determine anything useful since I don't know which phone...

I do have one success on the automated lights and that is the ones that come on when you open various doors.

Thoughts?

 

[AnthonyZ]

I do a fair amount of automated (as opposed to centrally controlled) lighting. I call it a 'hands in the pocket' approach. Yes, much of the lighting is timed and I use flags (HAI guy here) to track lighting states and occupancy. This allows a conditional look at the system and saves me the headache of having to field complaints from my wife. It can be complicated but much of what we do is just that.

 

[Timoh]

I haven't done it, but it's on my todo list...

When I do get a round to it, I'm going to pick and choose my battles. Hallways, yes. TV room, maybe. Bderoom, probably not. The reason being what decides it, is how and when you move.

If no motion is detected in a hallway, you can probably safely assume no-one is there and turn off the light. But watching TV, and you're quietly laying on the couch, the motion sensor might think the room is empty. (Short of waving at every few minutes). In the bedroom, how does the motion sensor know if you're moving asleep in bed or getting up?

The more info you can pump into a system re door sensors, light statuses, alarm, etc. the better. Lot's of folks are using a good night button, that puts the house into a night time mode. Turns off light, arms alarm, and activates your motion sensors to dim on motion.

Light status would be an easy one... Upon motion detection, check if light status is brighter than dim command. If it is, don't dim. If light is less than dim level, store current setting, increase to level desired, and return it back to the previous level after x minutes. 3-5 is probably a good value, and ensure it re-starts it's counter when tripped again.

Light the stairway? Why not. Maybe at a lower level, but I would do it at least a little bit in case someone is going for a midnight snack.

Tim

 

[TonyNo]

My motion sensors are used mostly for security (any motion and Away = problem).

The light control is minimal, such as my main foyer and laundry room. Motion turns on the light for five minutes. Additional motion gives another five minutes.

The fancy one is my master bedroom. I have two motion sensors by the door, next to each other, but angled apart. This yields sequential signals that can determine in or out movement.

I increment a counter on an In and decrement it on an Out. When the counter changes to >0, the light comes on. When the counter changes to <1, the light goes off. This works pretty well, but I need to add circuitry to the sensors to eliminate the several-second blind time after firing. These are Hawkeye-type sensors.

I also have some logic so that if there is internal motion and the light is off, it comes on for five minutes. During the day, the on-level is 100%. If the Bedtime flag is set, the level is 30%.

 

[cliffs]

I used this is my last 3 houses. Hall lights work the best. Two ways to do this, either trigger the
light from a motion detector or use the motion detecting switches. It works well in laundry rooms
and on the garage door that enters into a laundry room. When you open the garage to house door the
light automatically comes on. Great when you have a hand full of groceries.

I also use this type system to turn on garage interior lights.

In my last house I used motion detecting switches to turn on the bathroom
fans for 10 minutes. Sure makes the bathroom smell better.

With kids you can't win, they always leave the bathroom light on and their bedroom
lights on.

Another place is in walk in closets. I used a motion controlled switch here. Works best in a
master bedroom. It will turn the light off after you have crawled into bed, so you don't have to
stumble around in the dark.

After all these devices are to make your life easier and they are not expensive.

Cliff s

 

[robolo]

What has garnered high praise from the wife is motion sensors in the bathrooms that turn lights on slow and dim when she gets up to go in the middle of the night. I have it connected to ELK M1. It is triggered if there is motion detected after sunset, I keep it on for 10 minutes after the last motion is detected (if motion is detected during that time the counter is reset to 0) and it works great. Doing the same thing for hallway lights makes good sense for kids that have to get up in the middle of the night.

I also have a motion sensor turn off one of my hall lights after an extended period of inactivity - like 30 minutes. As for the stairs that really depends if you expect people to come out of the room at night to go down the stairs. I think you might be best to limit it to the bathroom path. If someone wants to go downstairs they are probably more awake and so can turn it on themselves. That is my 2 C worth

 

[pdwitt]

Does anyone have experience with or knowledge of the use of occupancy sensors for this type of application rather than motion detectors?

 

[123]

ToMAYto, toMAHto, http://www.cocoontech.com/index.php?s=&amp...ost&p=76955

 

[rhughes]

True occupancy sensing is a tricky thing. You can simulate it with motion sensors with timeout rules, but results vary. A couple years ago I put some time into prototyping a system that used a camera and some custom pattern matching software(actually texture matching to eliminate problems with lighting conditions changing over time) that I wrote, and had a fair amount of success, but lost interest when work demands increased.

I ended up using motion sensors (both wired and wireless) and HomeSeer to turn Insteon-based lights on and slowly fade them off over a minute or so. This allows us to move through the house at night without flipping switches on and off. If we want to stay in a room, then we just turn the switch on. The HomeSeer event rule only fires the action if lights in the vicinity are off and it's night time. For bathrooms, I also have a door sensor that causes HomeSeer to keep the light on if the door is shut (with a 10 minute no-motion timeout to turn the light off in case someone just shuts the door). All of this works really well for us.

 

[WayneW]

Does anyone have experience with or knowledge of the use of occupancy sensors for this type of application rather than motion detectors?

Please define "occupancy sensor". IMHO, there is no such thing as a single occupancy sensor as determining occupancy is way too complicated. The only real bulletproof solution is RFID tagging with many antennas and complicated triangulations algorithms. A rule based system can use a multitude of sensors (PIR, microwave, photo-beam, acoustic level, light level, pressure mats, pressure switches, capacitive loops) to try and cover most scenarios. For example, one could use a pressure sensor on a bed to determine occupancy. One could put a magnetic contact on the footrest of a recliner to partially determine occupancy. One could put a mercury switch on a recliner or rocking chair to determine occupancy. Some of these sensors are absolute on/off, some are only triggers for timers that eventually expire and the status becomes indeterminate.

 

[CollinR]

I too am holding off for RFID the commercial stuff I have seen is very effective and precise. You may notice your new Mitsubishi automatically falls in line at the service bay of the dealerships. They have access to a system that tracks all the cars on the lot and stores their positions to less then 4" (including altitude for 2 story houses).

Basically the hardware technology is already there but the software to actually make it a viable product is not. When compared to the cost of many motions especially nice motions the hardware itself may actually be cheaper the labor to install no doubt is.

 

[deranged]

Most of my "Automated Lighting" for most areas of the house is setup to turn lights off in steps.

If no motion is detected after a delay the lights Dim by X%. ( any new motion will reset the timers )
If no motion is detected after another delay the lights Dim again by X%.
Then after another Delay the lights turn off.

In some places the Delays are 10 Minutes and in other places the delays are a minute.

In rooms that are used mostly for myself the lights turn on automatically either when the door is opened or by motion.

The Main Hallway, Bathrooms and stairs automatically turn on if there is any motion in those areas after dark and then turn off by the above rules.

This so far has had a very high WAF, and I know at least if a light is left on it will eventually turn off.

That along with a button near the bed that will turn on *EVERY* light internally and externally, another high WAF item.

StevenE

 

[HoustonFirefox]

I have a motion sensor in the kitchen that turns on the light for 5 minutes and will reset for any additional 5 any time motion is detected. That's pretty normal.

My most important use for occupancy sensing is with regard to arming my Elk M1.

1) If no motion is detected in the living room for 45 minutes then the system arms automatically to STAY mode (interior motion will not trigger set off alarm).

2) Additionally, if no motion is detected within 14 hours after the last detected living room motion then it arms immediately to AWAY mode. (STAY mode has already been in force by this time).

This is to prevent me from accidentally forgetting to arm the Elk when leaving the house (not really a problem with me, but is with the kids).

In the 2 years I've been running these rules, I have never once had a false alarm. If you don't move in the view of the living room sensor within 14 hours then you are (1) Deathly sick in bed with the flu (2) Truly away from the house or (3) Dead.

Not really occupancy sensing, but kind of neat: I have an automated dog feeder (load it up with food) and it has a motion sensor looking down from the eave of the house. If my dalmation comes along and wants a bite, then it determines if it's time or not to feed him based on his motion, then triggers a measured amount of food out. He's gotten very well trained at how to get his kibbles. I thought about using an RFID FOB on his collar but this works surprisingly well.

Ooopps, almost forgot. At midnight a "DayChange" flag is set to 1 in the Elk. When the system detects it's first motion of the following day then it greets me with the current time, date and temperature. It does this only once since it resets the DayChange flag.

Just for fun, during the weekdays I have to be at work by 8am. If it doesn't detect motion anywhere by 7am then it "bleeps" the alarm siren for 1 second at 5 minute intervals. Every time it "bleeps" then it increases the time by one extra second so 25 minutes of no motion will yield an alarm/piezo scream for 5 seconds. After an hour you have a full 12 seconds of noise trying to get you up. Gentlemen, I can guarantee you'll NEVER be late for work again

"Food" for thought: If you have a garden then remotely wire a motion detector to it with a piezo screamer on it. I had a severe problem with squirrels, birds, deer, etc eating my veggies. No more! I've sat there and watch the little critters trip this thing and they don't do it any more! The plants moving in the wind don't seem to trip the detectors so it works great!

just thought I'd toss in my .02 cents

 

[pkoslow]

Does anyone have experience with or knowledge of the use of occupancy sensors for this type of application rather than motion detectors?

Hi Paul,

I've used both Leviton ODC20-UOW and ODC20-UOW in the past which are true occupancy sensors. Regular motion sensors are fine for traveled areas like halls and I also have good success using regular motion sensors in combination with door contacts to automate lighting in places like closets, laundry room, garages and other places where you don't often remain motionless for any period of time.

To get accurate occupancy in rooms like offices, TV rooms, etc. where you tend to stay in one spot for a long time, a true occupancy sensor is the only way to do this accurately. The ultrasonic Leviton units I mentioned above can even pick up movement in an office cube when the persons head is not in line of site of the sensor (they can basically hear around corners). In residential settings, these will pick up the motion of you turning the page on a small paperback book, typing on a keyboard or even just moving your thumb around to channel surf. This is the kind of stuff that a regular motion sensor can't do well.

On the flip side, these don't make good "security" sensors, so you'll also want a regular PIR motion sensor in the room if you need security.

Cheers,
Paul

 

[BryanE]

Paul,

Can you hook an ODC20-UOW up to an Elk?