Ambient Sensing
Environmental Sensors
The Environmental Sensor is a small white box that will be attached to a wall in most rooms. It detects:
- Human presence within a room, via a Passive InfraRed (PIR) sensor.
- Temperature
- Pressure
- Humidity
- Light levels
When combined with wearable location data, we can more accurately locate participants within the home, and even detect and filter-out visitors and pets.
The sensor runs on a battery and doesn't connect to any wires or need plugging into a socket. Data is stored locally on the device until it can be sent back to the SPHERE Home Gateway hub using a mesh network via the SPHERE Gateways dotted throughout a participant's home.
Here is a short clip, created for SPHERE participants, that explains how it is installed and what it does:
Secondary Sensors
The environmental sensor's PCB includes a break-out connector. This allows us to add additional PCBs and sensors to collect other sources of data, including:
- Water flow through pipes into the sink, toilet, shower or bath, using either a mechanical flow or acoustic contact-microphones.
- Electricity usage, using either ferrite loops or Hall-effect sensors.
- Vibration, using mercury-tilt switches, or accelerometers.
- Door opening, using magnetic switches.
We have also experimented with particulate and pollution detectors, as well as area microphones detecting ambient sound and volume levels.
Appliance Usage Monitoring
Appliance Monitors help detect what kinds of acitivites are taking place in the home by monitoring electricity use. They are plugged into things like TVs, microwaves and kettles.
We also attach a mains supply monitor in houses to detect spikes in usage that might be caused by emersion heaters, showers, and ovens.
This short clip, created for SPHERE participants, explains how the appliance monitoring operates:
