Reliable UAV navigationwhen GPS cannot be trusted.
KALGARD Systems develops onboard navigation and georeferencing technologies for drones operating in GNSS-denied, jammed, spoofed, or unreliable environments.
Focus
GNSS-denied
Navigation for degraded or unavailable satellite signals.
Approach
Onboard
Onboard estimation with periodic absolute correction from observed environmental features.
Stage
Flight-proven
Astrel is flight-proven; the wider MerlinSight lineup is in development.
Current product
MerlinSight Astrel
System note
MerlinSight Astrel, the positioning module of the lineup, keeps a continuous onboard position with periodic absolute correction, with no GNSS or datalink dependence in flight.
Flight validation
Real flight testing has demonstrated under 5 m mean 2D error, including a flight test with an army regiment.
Why this matters
Reliable positioning is a hard requirement for UAV operations, yet GNSS is not always available or trustworthy.
KALGARD is building navigation systems that help drones maintain localization and mission continuity when satellite signals degrade, are spoofed, or disappear.
Development context
Hardware and flight integration work focused on practical UAV deployment constraints.
What the MerlinSight lineup delivers
KALGARD technologies give aerial platforms trusted answers where satellite positioning cannot be relied on.
Astrel
Position of the aircraft
Onboard navigation that keeps a trusted position when GNSS is jammed, spoofed or absent: a continuous position with periodic absolute correction. Flight-proven, with under 5 m mean 2D error measured in real flight.
Explore AstrelArrow
Observed points
An observed point becomes a ground coordinate. Stealth, with no EM wave emission.
In development
Sillage
Mapping
Maps of overflown areas, updated by every flight.
In development
MerlinSight
MerlinSight is the KALGARD product line for flying without GNSS.
Astrel, the positioning module, is the current flight-proven product. Arrow and Sillage extend the lineup and are in development.
Flight-proven product
Astrel
The positioning module. It sits on the aircraft and preserves navigation when GNSS is jammed, spoofed or unavailable.
Delivery
Available as a full module combining sensors, compute and software. Software-only integration on existing hardware depends on the platform’s sensors, synchronisation, compute and flight-control access.
System overview
Astrel provides GNSS-independent absolute positioning: a continuous onboard position with periodic absolute correction, for UAVs that must keep operating when satellite positioning is unavailable or untrustworthy.
Visual-inertial estimation
Onboard estimation from camera and inertial sensing maintains a continuous position solution between corrections.
Absolute map correction
The downward camera view is matched against preloaded georeferenced reference data to correct the position with absolute fixes during flight.
GPS-like integration
Latitude, longitude and altitude are output to the flight controller as GPS-like NMEA or MAVLink. No autopilot modification, no GNSS or datalink dependence in flight.
Correction approach
Map-based localization
Astrel corrects its onboard estimate by matching the downward camera view against preloaded georeferenced reference data, keeping the position continuous with periodic absolute correction when GNSS cannot be relied on.
Evaluation
Measured in real flight
In real flight testing, Astrel has demonstrated under 5 m mean 2D error, measured post-convergence against GPS ground truth. The figure shows a flight test performed with an army regiment.
Flight test with an army regiment
3.43 m
Mean 2D error
4.24 m
Mean 3D error
1.76 m
2D standard deviation
5.74 m
2D p90
1.55 m
Altitude MAE
5m 17s
Flight duration
The flight duration was set by the authorized flight zone. Astrel is designed to keep a continuous position with periodic absolute correction rather than let dead-reckoning error accumulate with elapsed time; longer and more varied flights are part of ongoing validation.
The rest of the lineup
Arrow
Georeferencing of observed points
An observed point becomes a ground coordinate, ready to report and share. Stealth: no laser, no EM wave emission, nothing that gives the aircraft away.
Sillage
Mapping from flight
Flights become maps. Every flight updates the map of the area it covers, georeferenced, without any GNSS.
Where our technologies apply
KALGARD develops onboard navigation and georeferencing technologies for aerial platforms operating where satellite positioning is degraded, denied or insufficient.
Defence & security
- 01Operations through jammed or spoofed airspace
- 02Deep reconnaissance beyond the reach of a reliable data link
- 03Mission continuity when GNSS is lost mid-flight
- 04Reporting the position of observed points of interest, in ground coordinates
Civil & critical infrastructure
- 01Operational continuity for critical infrastructure exposed to interference
- 02Inspection in urban and constrained environments where GNSS degrades
- 03Search and rescue
- 04BVLOS corridors independent of GNSS availability
Capability detail, performance figures and integration data are shared with qualified partners under NDA.
System walkthrough
Navigation that recovers when GNSS disappears
From visual-inertial estimation to terrain-matched correction, this sequence shows how MerlinSight Astrel contains drift and brings the aircraft back onto a trusted trajectory.
Research to product
KALGARD Systems is an INRIA-incubated company focused on resilient UAV navigation.
Focused technical development
The company is building the MerlinSight lineup at the intersection of onboard perception, navigation, and UAV integration.
Incubation
The company is being developed with INRIA incubation support.
We are looking for partners to help MerlinSight bring autonomy and resilience to drones.
KALGARD is opening conversations with organizations interested in resilient UAV navigation, field validation, and operational deployment.
KALGARD
Systems
UAV integrators
Explore MerlinSight Astrel integration on existing drone platforms.
Defense and civil end users
Discuss operational needs and validation scenarios in GNSS-degraded environments.
Investors
Support the next stage of product development, testing, and market access.
Aeronautics and robotics, built into one team
KALGARD brings together aerospace engineering and advanced robotics expertise to develop resilient navigation systems from research through flight integration.
Jules
Founder · Aeronautical Engineer
Imperial College London
Aeronautical engineering expertise focused on UAV systems, product development, and bringing MerlinSight into operational flight environments.
Thibault
PhD in Robotics · Engineer
ISAE-SUPAERO
Robotics and engineering expertise focused on autonomous navigation, onboard perception, and resilient localization.
Start the conversation
We welcome conversations with UAV manufacturers, defense and aerospace partners, public innovation stakeholders, investors, and engineers interested in the problem space.
Call to action
Partnerships, pilots, and technical discussions.
Get in touch if you are exploring resilient navigation, integration into a UAV platform, investment, or opportunities to work together.