GPS-Denied Navigation

Reliable UAV navigationwhen GPS cannot be trusted.

KALGARD Systems develops onboard navigation technology 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 correction from observed environmental features.

Stage

Prototype

Active development, flight testing, and technical validation.

Current program

MerlinSight

MerlinSight by KALGARD
MerlinSight prototype navigation module

System note

MerlinSight is being developed as an onboard module for resilient localization in degraded environments.

Flight validation

Test flights have demonstrated localization error below 5 m, including in a defense evaluation context.

Mission

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.

Prototype and UAV integration work in the KALGARD workshop

Development context

Hardware and flight integration work focused on practical UAV deployment constraints.

What We Build

MerlinSight

MerlinSight is an onboard navigation system for UAVs designed for GPS-denied operation.

It combines onboard navigation with map-based correction from observed environmental features to support robust localization in degraded environments.

Onboard architecture

Prototype module

Onboard architecture

Designed to sit on the aircraft and preserve navigation when GNSS quality breaks down.

System overview

MerlinSight provides a resilient onboard localization layer for UAVs that need to keep operating when satellite positioning becomes unavailable or untrustworthy.

Visual-inertial navigation

Onboard estimation from camera and inertial sensing to maintain a continuous position solution.

Map-based correction

Uses observed environmental features and trusted reference data to correct drift during flight.

UAV integration

Built to support onboard navigation decisions on operational UAVs, not just post-flight analysis.

Public-safe map correction visualization with observation tracks over grayscale reference imagery
Public-safe feature overlay visualization for map-based correction

Correction approach

Map-based localization

MerlinSight performs map-based correction by comparing observed environmental features with trusted reference data, reducing drift when GNSS cannot be relied on.

Test flight plot comparing GPS ground truth in blue with MerlinSight estimate in green
GPS ground truthMerlinSight estimate

Evaluation

Flight-tested precision

Across flight testing, MerlinSight has demonstrated sub-5 m mean localization error. The figures below show one defense evaluation flight as an example, using post-convergence comparison against GPS ground truth.

Example defense evaluation flight

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. MerlinSight is designed to correct drift against reference observations during flight, rather than let dead-reckoning error accumulate with elapsed time; longer and more varied flights are part of ongoing validation.

Applications

Where it fits

MerlinSight is relevant to UAV operations that need resilient localization when GNSS performance becomes unreliable.

Defense and security UAVs

Critical infrastructure monitoring

Operations in GNSS-degraded environments

Credibility

Research to product

KALGARD Systems is an INRIA-incubated company focused on resilient UAV navigation.

Focused technical development

The company is building MerlinSight at the intersection of onboard perception, navigation, and UAV integration.

INRIA campus seen from the sky

Incubation

Inria logo

The company is being developed with INRIA incubation support.

Workshop testing and prototype preparation
Partner Search

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.

UAV integrators

Explore MerlinSight 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.

Recruiting

Join the engineering effort

KALGARD is currently recruiting an R&D Engineer in Autonomous Navigation and Embedded Systems through INRIA incubation.

Open role

R&D Engineer, Autonomous Navigation and Embedded Systems

The role focuses on MerlinSight development across embedded navigation, onboard perception, hardware integration, and field validation.

LocationSophia Antipolis
ContractFull-time CDD, 10 months
Target start dateJuly 1, 2026
Apply byMay 24, 2026

Profile

Advanced C++ or Python, embedded systems, navigation.

The position is aimed at engineers comfortable with real-time systems, state estimation, and onboard UAV software.

View Official Job Offer
Contact

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.

Contact Information