This DIY Bed Sensor is super easy to make…and works in HomeKit!

Summary

• The video demonstrates how to build a DIY pressure/weight sensor “bed mat” that can trigger Apple HomeKit automations.
• The build is designed to require no soldering or advanced tools, using inexpensive, readily available Amazon parts.
• Motivation: automate smart-home actions based on when someone gets in/out of bed, avoiding dependence on motion sensors.

Example automation ideas mentioned

• Turn on the bathroom lights when someone gets out of bed.
• Trigger the TV or scenes at specific times, or when someone sits/gets into a seat (bed, couch, desk chair).
• Provide caregiver-style alerts/notifications when someone gets up (including a possible front porch notification concept using a sensor under a mat).

---

Key hardware concept

• Use a pressure mat/bed sensor (originally intended for caregiver/nursing use) that has a wired connection.
  • The specific model used in the video included a wire attached, simplifying DIY.
• Connect the pressure sensor output to a type that an Aqara hub can interpret, enabling HomeKit integration.

---

What you need

• A pressure sensor / bed sensor mat
  • Multiple sizes/versions exist; the creator links the exact one used.
• An Aqara Hub (required for using Aqara sensors in HomeKit).
• Aqara sensors for two possible integration methods:
  1. Aqara Contact Sensor method (easy / super easy version)
  2. Aqara Water Sensor method (super easy version)

---

Two methods to integrate with HomeKit

Method 1: Aqara Water Sensor (simplest wiring, but “leak” issue)

• The pressure sensor mat is wired to the Aqara water sensor terminals.
• When weight is applied to the mat, the water sensor is triggered.
• Limitation: even if notifications are turned off, the Home app will still show a “leak” indicator whenever the mat detects weight.
  • The creator notes this may be acceptable if you mostly automate through the Aqara app or Home Assistant.
  • It’s not ideal for users who regularly open the Apple Home app.

---

Method 2: Aqara Door/Contact Sensor (preferred for HomeKit cleanliness)

• To avoid the unwanted “leak alert,” the creator repurposes the pressure mat to emulate an open/closed (reed-switch) style status using an Aqara door/contact sensor.

• DIY steps (no solder required; optional disassembly):

  • Disassemble the door sensor slightly to access the reed switch connection points (“read sensor” described as a tiny tube).
  • Find the mat’s relevant wires.
    • The mat had 4 wires total.
    • The creator tests which ones to use using a multimeter or by using an Aqara sensor to observe triggering while pressing wires.
    • In their build, they used black + green wires.
  • Wrap the mat wires tightly around the reed switch endpoints.
  • Reassemble the casing.
    • For non-solder builds, use electrical tape for securing and strain relief.

• Benefit: HomeKit displays a simple open/closed state instead of a “water leak,” resulting in cleaner automations and notifications.

---

Testing / behavior notes (important practical analysis)

• This DIY sensor needs trial and error:
  • Placement under the bed/mattress matters.
  • Mattress/box spring materials can affect detection.
• Sensitivity / weight considerations:
  • The creator (and spouse) could trigger it.
  • A smaller child (described as 12 years old) did not trigger it reliably, suggesting limited sensitivity for lighter weight.
• Coverage limitation:
  • The setup described detects weight on one side of the bed.
  • To detect both sides, you’d need a bigger sensor or another mat.

---

Results / automations used

• Currently used on the bed for:
  • Turning on a bathroom light during the night.
  • Triggering a bedtime TV scene when first laid down.
• Considering moving it to a couch in a studio to trigger TV + lights when someone sits.

---

Main speakers / sources

• Speaker: Shane (host of the channel; mentions building “easy Apple Home Smart home” projects).
• Product source/brand mentioned: Aqara
  • Aqara contact/door sensor
  • Aqara water sensor
  • Aqara hub
• Pressure mat source: an Amazon-sourced pressure/bed sensor mat.