Drone detection

Hear the drone.Find it.Point at it.

A low-cost system that hears small drones by the sound of their propellers, works out the direction they're coming from and turns a camera turret to confirm and track them.

Azimuth000.0°
Elevation00.0°
Source12-mic
Update60 Hz
EmissionNone
01 — The asymmetryWhy sound
01 / THE GAP

Hard to catch

Radar is expensive and struggles with small, slow, low targets. It is also loud: it transmits all the time, so an enemy can detect it, find where it is and target it. RF detectors miss drones flying without a radio link.

02 / OUR ANSWER

Impossible to silence

Every drone has one thing it cannot hide: the sound of its propellers. We listen for it, and that is all we do. Our system is silent. It sends out no signal, so an enemy has nothing to detect.

02 — Listening unitStatus: working
CAD render of the listening unit, with microphone mounts extending from two levels around a central column Fig. 02 — Listening unit · CAD render

Twelve ears.
One direction.

Twelve small microphones listen at once. A drone's sound reaches each one a few microseconds apart. From those differences we solve for direction, left–right and in height.

A microcontroller samples all twelve in lockstep. An FFT picks out the propeller signature, direction is solved 60 times per second, the track is smoothed while the drone moves, and a rough size estimate goes live to the operator.

Mic 1+0 µs
Mic 2+0 µs
Mic 3+0 µs
Mic 4+0 µs
Coverage
az 0–360° · el 0–90°
Detection range, small camera drone
≈ 40 m, extending
Direction updates
60 / s
Camera tracking response
30 ms

Prototype figures · full benchmark in progress

03 — The chainHear → Point → See → Act
01

Hear

The listening unit hears the drone from any direction, day or night, even when nobody can see it.

02

Point

The approximate bearing goes to the turret, which swings its camera that way.

03

See

An on-board AI model confirms the drone in the image and keeps it centred, on its own.

04 · Next phase

Act

A countermeasure mounted on turret v2, then cheap interceptor drones.

The operator's view

Recorded during an outdoor test: camera with the drone locked, sound direction on the listening hemisphere, motor and tracking state. Everything runs on the turret, with no internet connection.

Keystone user interface: camera feed with locked drone, 3D sound-direction display, motor status and track lock
Target · locked
Sound bearing
Track phase
04 — Turret v2Status: being built

Stiffer.
Effector-ready.

Designed in CAD and now being built: a stiffer frame, our own drive on both axes and a mount for a countermeasure. It is the base for the next phase.

Turret v2 CAD, side view Turret v2 CAD, front view
05 — Roadmap● done ○ next
  1. Done

    Listening unit + turret v1

    Both working and tested outdoors with real drones.

  2. Building

    Turret v2

    Stiffer frame with a countermeasure mount.

  3. Next

    24-microphone array

    Listening unit v2, with twice the microphones and a longer range.

  4. Next

    Networked units

    Several units together measure distance, not only direction.

  5. Final goal

    Interceptor drones

    The recognition model moves onto the interceptor itself, with no radio link to jam.

06 — Team

Jost Benedičič

Mechanical engineer · CAD models

Domen Roblek

Mechanical engineer · CAD, electrical system, motors

Jaka Ropret

Software · Microphones

Lovro Zupan Škrlj

Software · Microphones

Bor Jenko

CAD, CAM and CNC milling