Tethered Drones & UAVs

Tethered Drones and Unmanned Aerial Vehicles

What is a tethered drone system?

A tethered drone system uses a permanent physical link, in the form of a flexible wire or cable, to provide power and communications to a UAV. Due to the inability of fixed-wing drones to hover, UAV tether drone systems utilise quadcopters or other multirotor drones, as well as aerostats. They are used for situations where the required flight endurance is greater than that of the free-flying drone, and only a minimal operating area is needed.

Drone tethers typically provide up to a few hundred metres of operational altitude, with the limiting factor being the ability of the drone to support the weight of the tether. Drone tethers may be made of aramid or other lightweight synthetic materials to provide strength, with copper or plated copper for power conduction and optical fibre for data and communications. The system may be based on the ground or on a vehicle.

Elistair Safe-T tethered drone system
Elistair Safe-T tethered drone system

Tethered drone power and flight systems

The ground station of a UAV tether system will supply power to the drone and its payloads from a connection to mains electricity, or to a generator. There may be a battery backup in case of outages in the main power source.

The ground station may include smart power management, as well as automated tether winding with GNSS positioning to maintain flight ceiling and position even in adverse weather. Status monitoring, health checks and fail-safe procedures for the drone may also be built in.

Persistent Drone Tether
Persistent Drone Tether
Acecore Drone Tethering System
Acecore Drone Tethering System

Applications of UAV tether systems

The most common use of tethered drones is to provide a persistent surveillance capability for situational awareness. This may be used for military ISR (intelligence, surveillance and reconnaissance), disaster response, event management and security, traffic monitoring and a variety of other applications. Data transmitted via fibre optic drone tether has the advantage of being more secure as it is less susceptible to interference than wireless signals, and cannot be jammed like RF signals.

Powerline tethered drones are also used as part of long-range communications relays to create temporary networks for cellular, radio and broadband internet signals. Research is also being conducted on the use of UAV tether systems for power generation via the harnessing of wind energy.

Tethered drones can be outfitted with a range of payloads to suit the particular mission, including IR and HD video cameras for real-time streaming, radio repeaters and environmental sensors.

Orion UAS Tethered Drone
Orion UAS Tethered Drone