Have you ever tried to use the FSR strips to calculate the weight?
TTS on Jan 01: “You have gain weight through Christmas and now your weight is 98 kg”
Would be so cool to keep track on weight over several months. I know the pressure will be different depending on how you are positioned in bed, move etc but as a rough measurement.
I won’t stop you, but there are a variety of challenges and reasons I think you’ll have a hard time achieving your desired result.
FSRs can detect weight, but they are not very accurate at estimating the exact amount of weight. FSRs are a good choice for detecting if something has been pressed or squeezed, but not for precisely measuring how much force is being applied. And that’s before you add in the dynamics of how the mattress spreads the load, how you are laying in bed, or if you have a partner on the other side of the bed.
FSRs have a nonlinear response. I don’t think a few kgs of weight difference will register in that part of the sensor range, and if it does it will be a very small amount.
It might be able to detect if you’ve gained 10kg, but I don’t think that’s the resolution you’re looking for.
Will this work if I have a bed frame with slats, then a box spring, then the mattress? Plan would be to install it on the slats and have it underneath the box spring and mattress.
I put one in the crib (and also had no idea what I was doing baby-wise). Our crib doesn’t have slabs, but a single sheet that does bend a little — enough to do sleep detection.
But here are the other practical challenges:
Our one has until now (17 months) very seldom slept in the crib. Babies are just babies. Don’t have too many expectations on this front.
They sleep whatever way and may not affect the sensor sufficiently, like being too much to the side or something.
They can move a lot, which affects the sensitivity.
They’re light, which affects the sensitivity. I calibrated with a dumbbell.
Good luck to you! It can be challenging, but massively rewarding and amazing.
(My automations until now have been to track sleep and to turn lights on or off.)
This product looks amazing, I appreciate the work done to take this from DIY to a finished product. Is there any chance you can offer alternative shipping services for Canadians ? UPS and DHL can charge up to $40 to collect $5 in duties, while USPS/Canada Post is $10 (if even charged). Sorry to pollute the thread but UPS/DHL shipping options are stopping me from ordering right now.
Even though it’s over, the Canada Post strike is still affecting shipments to Canada. Due to the backlog, affordable options are still limited. When available, we use Asendia, which uses Canada Post for last mile delivery. We’ll reintroduce that option as soon as it is available to us again.
As you say, babies don’t sleep in just one spot, but perhaps you could use the extensions to place both sensors different areas of the mattress to increase the ability to detect them in multiple locations? A dumbell is a great way to test having the weight in many different parts of the crib to test out what readings you’re getting.
Although I will say that thinking about cribs, I feel like the idea mentioned above around using weight sensors under the legs of the crib could be neat… in theory you could have a graph that captures daily information about how your baby weighs, in addition to knowing if the crib is occupied or not.
@Purpleturtle I have a bed like yours and when I saw the product and the dedication to HASS and FOSS I immidiately fell in love and wanted one - even though I’m in EU and will be economically raped when importing from US…
So I’d really like to know if anyone got this to work. @stephenp93 do you know?
Very excited, ordered some days ago (before the holiday) and my order has just shipped today! (that’s not a dig by the way, when I ordered the website took great care to ensure that I understood any orders placed during the holiday were not going to be processed until the 7th of January, so things went exactly as planned, very happy about that!)
After reading through the entirety of this thread, and an old one about using FSR’s, I’m going to explain my bed/mattress setup along with how I intend on using these.
I have a queen size memory foam mattress, on top of a separately built “metal frame boxspring” (pictured below), which then sit about 15 inches off the floor in a bedroom furniture set “bed frame”. So distance from top of mattress to the floor is about 40 inches.
That “metal skeleton” above is covered with a zip on fabric cover. After having read this thread, it seems that memory foam can cause issues with the sensors over time or them having a lot of “creep” as the foam compresses/decompresses. How I’m going to install these with the hopes of resolving that/making it less of an issue, is as follows:
I cut some quarter inch thick wood to 24 inches long, by 3 inches wide. I’m going to mount the sensors onto the metal frame and then sandwich them by placing the wood on top of the sensor. I’ll be holding the wood slats in place using zip ties (not tightening them aggressively, just enough to keep them there. I’ll be drilliing a small hold into the metal frame for the mounting of the unit itself, and using the extension wires so I can mount it underneath the center rail. I’ll then cover the whole thing back up with the fabric cover.
So the final “order” of things will be:
mattress → fabric “metal bed frame/boxspring” cover → .25" thick by 3" wide by 24" inch long wood slat → FSR sensor → metal bed frame/boxspring
The reason for this is the wood slat will increase the surface area of the mattress that’s in contact with the particular slat the sensor is on, thus increasing pressure being placed upon the sensor, not only by being larger and being in direct contact with more mattress than the other slats, but also being a quarter inch “higher” than the other slats. I’m hoping this will resolve any sensor creep/other issues caused by memory foam.
Our bed sensor arrived and is now installed after testing. It’s working flawlessly.
So, now I just need some inspiration about what people are doing with them? I’ve created a basic automation that turns off our audible announcements when we’re in bed then turns them on again when we get up. Next step, I guess, will be something that shuts down the house at night when we’re both in bed and wakes it up again in the morning when we’re both up.
Has anyone created a decent blueprint that uses bed presence for multiple functions?
I’m following this topic out of interest and like the idea of using a bed presence sensor.
Now, I have zigbee buttons on the bedside to control stuff and 1 of them is used to put the house in night mode.
I really wonder if it’s possible & how to tackle irregular schedules and the distinction between getting up briefly and really starting the day for lights, alarm, …