Perhaps, though I’m not sure how decompression would affect the weight, but perhaps it affects weight distribution. 25 min also seem long, but I don’t have a memory foam mattress.
I definitely see this with my memory foam mattress.
This graph is pressure experience by the FSR, but you can just think of it as the inverse of resistance. So for my setup, the resistance sky rockets right when I get out of bed, then decreases over time and levels out.
My theory is that the mattress rebounds up when you get out of bed (decreasing the weight on the FSR), then increases its weight on the sensor as the mattress fully relaxes.
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Working on putting together a bed presence sensor using 24" FSR’s. Currently trying to get 1 sensor squared away completely, before I install the second. I have a memory foam mattress. The memory foam is transferring some of my wife’s weight onto my sensor.
Would it make sense to change out my resistor to “zoom in” on the voltages to give a wider range gap between me being directly over the sensor, and the incidental pressure transfer from my wife being there?
My brain tells me there would be less false positives because of increased accuracy where it matters.
Would a flat base work with these FSR sensors?
I searched this thread but don’t see anything about using this if you have a flat base (no slats). I have a tempurpedic matress and it was installed on a flat base. I believe it’s a pegboard on top of slats.
TIA
I imagine that would work fine. I have a stiff metal box spring my mattress is on. Ended up laying an 8" wide piece of plywood across it between the box spring and the mattress to have a place for the sensors. It doesn’t have any issues picking up pressure.
Sorry if this is a stupid question.
As a European I don’t recognise the symbol used at r2.
Thanks for all the write up!
There are two parts, an FSR and a resistor. You recognise the resistor so what do you reckon the other symbol is?
It’s not a cultural phenomenon. It’s electronics. 
In which case, why not label it as such and prevent any further confusion 
I’m closing this topic as it is no longer the best bed presence detector and I no longer use it or support it. I use this: Bed Presence for ESPHome by Elevated Sensors
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Seeing that reddit found this post and is making up conspiracies…
Tom does not make the device linked above.
He does not want to support this thread or the original device. There is no conspiracy here.
Moderators are not Employed by Nabu Casa or Elevated Sensors. We are volunteers.
Also as a reminder, anyone has the option to flag any topic they create and have it locked if they no longer wish to support the project.
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