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Bhupendra Singh

Move through the room. You are the person it reads. Drop fast to fall.

occupied, moving, mid-room

Raksha

A room that knows you are there. No camera.

Millimetre-wave radar reads movement, distance and the rise and fall of a chest. It can tell an empty room from a sleeping one and a sitting person from a fallen one, and it does all of it without ever forming a picture.

Lens
None, ever
Leaves the house
Nothing
Sensor
mmWave radar

What a family would see.

The hardest question in this project is not the radar. It is how a device like this proves it is working, when working means nothing happens. This is a proposed answer, built as a working prototype. Open a room, or simulate a fall.

  1. 01Proof of presence, not a picture. The home screen shows that each room is being read right now, and what it reads, in words.
  2. 02An alert you can answer. A fall starts a short, clear sequence, and every response teaches the sensor something.
  3. 03The limits on screen. What it cannot see is part of the app, not the small print.
Design concept with sample data. Raksha is a prototype and has no app yet.

What it can tell apart.

Radar does not see shapes. It sees things moving toward and away from it, and how far off they are. Almost everything useful comes from that one measurement.

  • empty / occupied

    A room with nobody in it returns a still signal. A person breathing does not, even asleep and perfectly motionless otherwise.

  • upright / lying down

    Height off the floor is a distance measurement, so standing, sitting and lying are three clearly different readings.

  • moved / fell

    Lying down is ordinary. Dropping quickly to the floor and then not moving is the pattern worth reacting to.

  • one / more than one

    Two people breathe at different rates and sit at different distances, so they separate into two returns.

What it cannot do.

The limits are the product. A sensor that could do more of this would be a sensor I would not want in my mother's house.

  • and there is no version of this that adds it

    Know who you are

    There is no face, no voice and no gait signature precise enough to name a person. It knows a body is present, not whose.

  • the reason the whole thing uses radar

    Produce footage

    Nothing recorded can be replayed as an image, because nothing image-shaped is ever captured. There is no archive to subpoena, leak or regret.

  • range and wall penetration still being measured

    Cover a whole house

    One unit reads one room, and thick walls and metal stop it. A house needs several, and each one is another thing to fail.

  • the thing that decides whether it ships

    Never be wrong

    A large dog, a falling object and a person can look similar to a sensor that only measures motion and distance. False alarms are the failure mode that gets a device unplugged.

What is true today.

Raksha is a board on a desk, not a product. There is nothing to buy and no date.

Working on the bench

  • Presence and distance readings from a single room, live
  • Standing, sitting and lying separate reliably in a quiet room
  • All processing on the device, with no network and nothing stored

Not solved

  • False positives, which is the whole problem, not a detail of it
  • What a household should actually be shown day to day, when working looks like nothing happening
  • Enclosure, certification, and everything else that separates a board from a device