Counter-drone defence with four layers: Swiss LOCUS programme relies on domestic industry

Expensive missiles against cheap drones – Switzerland does not want to go down this road. Its alternative is brought together in the LOCUS programme: research and development for low-cost, modular counter-drone defence, supported by the competence centres of Armasuisse Science and Technology (W+T), more than 20 domestic companies and ten partners from academia. How the system is technically designed, why it is being created in an unusual way and what comes next was explained by Markus Höpflinger, head of the Swiss Drone and Robotics Centre (SDRZ VBS), on the sidelines of the first Sicherheitsforum Drohnen Schweiz in Thun.

Experience from the war in Ukraine shows how fundamentally drones are changing modern warfare. Small, fast drones with a first-person view (FPV) in particular pose considerable challenges for armed forces: comparatively cheap and difficult to counter, they can destroy even high-value military systems. Classic air defence systems are often too expensive or technically not ideally suited to this threat.

This is where LOCUS (Low-Cost Counter-UAV System), the Swiss research and development project, comes in. The aim is a multi-layered defence system that detects and classifies micro- and mini-class drones and engages them as cheaply as possible. The lead is taken by the competence centres of Armasuisse W+T, specifically the Swiss Drone and Robotics Centre (SDRZ VBS), the Competence Centre for AI and Simulation (KISI) and the Centre for Energy for Defence and Security (ZEVS). Around 20 industrial companies from Switzerland are involved, plus ten academic partners.

Graduated defence against different threats

LOCUS is based on several coordinated layers of defence. It begins with detection: sensors are to detect and identify approaching drones. The system then selects the means of defence that best suits the threat in question. Electronic jamming, drones with capture nets, particularly agile interceptor drones and – as the last line of defence – a newly developed weapon station are planned.

The individual components are at different stages of development. Demonstrators already exist, but integration into a complete overall system is still pending. “Our goal is to have a modular design,” says Höpflinger. The various means of defence are to be usable both individually and in combination.

According to the plans, the protected area is to extend over several kilometres. Interceptor drones are also intended for more distant targets, whereas the weapon station is primarily intended for defence at very close range.

A weapon station designed specifically against FPV drones

The compact weapon station is particularly interesting. It was designed from the outset to counter fast, highly agile drones and entire swarms of them. Unlike common remote weapon stations, it is intended for extremely rapid movements: according to Höpflinger, the system rotates at more than 360 degrees per second and is therefore significantly faster than currently available solutions.

Added to this is a large elevation range: the weapon can be aimed up to 90 degrees upwards, which means that steeply approaching drones can also be engaged.

At the same time, the team placed emphasis on low weight. Without a machine gun, the weapon station weighs only around 16 kilograms. This is intended to make installation on existing vehicles, unmanned ground platforms or in fixed installations comparatively straightforward. Machine guns that are already in service were deliberately chosen as armament – this reduces costs and simplifies logistics.

One technical challenge lies above all in combining high speed of movement, precision and recoil resistance. Together with industrial partners, dedicated drive solutions were therefore developed that are also intended to withstand the considerable loads during firing.

Networked counter-drone defence with a common operational picture

A distinctive feature of LOCUS is that the individual defence systems are networked with one another. Several weapon stations are to share targets and coordinate how they engage them. What matters is not only defeating as many drones as possible at once. The system is also to take into account which weapon station can engage a target most efficiently and with the lowest risk to the surroundings.

This aspect is crucial above all for the protection of critical infrastructure, because projectiles that miss their target can themselves become a hazard. According to Höpflinger, the distance at which a drone can be effectively engaged depends heavily on its flight behaviour. With targets flying in a straight line, this also succeeds at longer ranges; with extremely agile FPV drones, on the other hand, the chances of success fall significantly. The effective range could then shrink to around 50 metres. One reason for this is the flight time of the projectiles: the greater the distance to the target, the harder it is to predict where it will be at the moment of impact.

Automated instead of manually controlled

Software plays a key role. LOCUS is based on an open architecture; among other things, it uses the ROS 2 (Robot Operating System 2) software platform, which is widely used in robotics research. Different sensors, effectors and controls can thus be integrated relatively quickly. Future components are also to be added without having to redevelop the system as a whole.

In the long term, counter-drone defence is to be largely automated. An operator then keeps an eye on several systems at the same time and can intervene at any time without having to control each individual weapon station personally. Höpflinger justifies this with the extremely short reaction times when fast FPV drones attack: especially in the last layer of defence, it is hardly practicable any longer to engage targets entirely manually.

The functions required for this are currently being developed step by step; for the time being, the components still operate largely independently of one another.

A reversed approach with Swiss companies

The way development is carried out is just as remarkable as the technology – if not more so. Instead of first setting out extensive military requirements and only then looking for a suitable solution from industry, Armasuisse W+T deliberately reverses this sequence with LOCUS. Höpflinger puts it like this: “We want to know what is technologically possible and can be implemented cost-effectively by industry.”

The role of the competence centres is to contribute requirements and ideas, bring companies and universities together and coordinate the work. They work out what the technical solutions look like in detail together with the partners.

In this way, the aim is above all to avoid two typical weaknesses of conventional defence projects: lengthy development and expensive custom military designs. Wherever possible, the programme therefore draws on commercially available technologies and components that are already established.

“We want to know what is technologically possible and can be implemented cost-effectively by industry.”
Markus Höpflinger, head of the SDRZ VBS

Timetable to mid-2028

Integration will be the focus of the coming months. The team has completed the first firing trials and tests of individual components; the sensors, the weapon stations and the other means of defence are now to be gradually brought together into a common system. Further trials with the complete system will follow in spring 2027, and the development is to have reached the corresponding level of maturity by around mid-2028.

However, this does not yet mean that product development has been decided. Rather, the competence centres of Armasuisse W+T hope that industrial partners will then bring the technologies to market maturity and develop them further together with the VBS (Swiss Federal Department of Defence, Civil Protection and Sport).

Höpflinger thus also sees LOCUS as an experiment in a different kind of military innovation – faster, more open and more closely oriented towards what industry is actually able to deliver. Whether the programme will become a model for further defence projects remains open. What is already clear, however, is that Switzerland wants to break new ground in counter-drone defence – in technology as well as in the pace of development.