Terrain Trafficability as a Core Enabler of Autonomous Operations in GNSS Denied Environments

The Badb project is addressing one of the most challenging problems in modern autonomous operations: reliable navigation in GNSS free environments. A core element of this challenge is determining the position of unmanned ground vehicles (UGVs) and unmanned aerial vehicles (UAVs) when GPS signals are unavailable or unreliable. However, accurate positioning alone is not sufficient. Effective autonomous navigation also depends on a broader understanding of the operational environment.

One crucial, yet often underestimated, component of situational awareness is terrain trafficability. Trafficability describes which areas of a landscape are traversable for specific vehicles and identifies zones where vehicles are likely to become immobilised. Incorporating trafficability into navigation and mission planning significantly improves operational efficiency and reduces mission risk.

Kappazeta brings years of experience in analysing agricultural processes, providing a strong scientific and methodological foundation for modelling landscape properties. Trafficability mapping focuses on whether terrain can support vehicles, equipment, or personnel without degradation of mobility. Two of the most critical inputs to this assessment are soil moisture and essential soil properties. While soil moisture varies dynamically in response to weather and seasonal effects, underlying soil properties determine how the terrain reacts to moisture and mechanical loading. Together, these factors define load bearing capacity, rutting risk, sinkage depth, and overall vehicle mobility.

For UGV operations, trafficability information is particularly decisive. When a vehicle must travel from point A to point B, multiple potential routes may exist. During the mission planning phase, trafficability data allows planners to select routes where the soil’s load bearing capacity exceeds the vehicle’s ground pressure, reducing the risk of immobilisation. Once the vehicle is operating autonomously in the field, unexpected conditions and events may still arise. In such cases, on board route recalculation that accounts for trafficability assessments can prevent further complications.

In both pre mission planning and real time decision making, a trafficability map layer can substantially increase the probability of mission success. Planning or navigating without this information increases the risk of vehicles becoming stuck, wasting valuable time on recovery operations, exposing assets to danger, or forcing long and inefficient rerouting.

While UAVs are not directly threatened by ground immobilisation, trafficability remains highly relevant for aerial operations. UAV mission planning frequently involves anticipating adversary movement, identifying critical routes, and estimating likely locations for enemy assets. Trafficability mapping supports these analytical tasks by indicating areas that are realistically accessible to ground forces.

By focusing analysis on trafficable routes, UAV based ISR missions can significantly narrow their areas of interest, conserving limited flight time. Similarly, understanding which routes can support heavy vehicles helps reduce the number of plausible enemy positions, such as artillery placements. As a result, fewer points of interest must be investigated, allowing faster and more focused intelligence gathering.

As of April 2026, Kappazeta has developed initial models for soil moisture estimation and terrain trafficability assessment, with ongoing work to refine and improve these capabilities. The next step for the consortium is to integrate the trafficability solution into the Badb ecosystem. Following integration, the trafficability models will be configured for the specific vehicles used within the project. This will enable realistic and vehicle specific assessments of terrain mobility.

Once these steps are completed, the consortium will move towards field testing the trafficability solution. These trials will be key to validating both the models and their operational value, ensuring that trafficability becomes a reliable and actionable component of autonomous navigation in GNSS denied environments.