Couldn’t find the exact one I ordered a few months ago, but this type of pressure sensor aliexpress link is apparently a common bed occupancy sensor type used when building medical beds for hospitals and care homes so staff can be alerted when a patient gets out of bed. I’m not sure the specific model I linked is quite right specs-wise, but the idea is that it goes on a slat or other surface between the matress and the frame that doesn’t necessarily get the full weight of the occupant, but still gets enough to measure on the sensor.
Couldn’t find the exact one I ordered a few months ago, but this type of pressure sensor aliexpress link is apparently a common bed occupancy sensor type used when building medical beds for hospitals and care homes so staff can be alerted when a patient gets out of bed. I’m not sure the specific model I linked is quite right specs-wise, but the idea is that it goes on a slat or other surface between the matress and the frame that doesn’t necessarily get the full weight of the occupant, but still gets enough to measure on the sensor.