Forest Fire All-Terrain Vehicle: Traction, Slope Stability and Firebreak Lab

Traction and Slope Stability

The performance of an all-terrain vehicle (ATV) is heavily influenced by the interaction between its tires or tracks and the ground. The angle of inclination, represented as θ, must be balanced against the frictional coefficient μ to ensure adequate traction. For a static situation, this relationship can be described by the equation tan(θ) = μ, where the vehicle will not slide if the tangent of the slope angle is less than or equal to the coefficient of static friction.

In dynamic situations, such as when climbing or descending steep slopes, additional factors come into play. The rolling resistance and the force exerted by the terrain on the vehicle must be considered. The ATV’s ability to maintain stability on a slope depends not only on its traction but also on its center of gravity and the distribution of weight.

Bekker Soil Sinkage

When an ATV traverses soft soil, it can sink into the ground due to the pressure exerted by its tires or tracks. The Bekker model is a widely used empirical approach for predicting this phenomenon. It takes into account the vehicle’s weight, tire characteristics, and the properties of the soil, such as cohesion and internal friction angle. By adjusting these parameters in the simulation, one can observe how different terrains affect the ATV's performance and stability.

Understanding the Bekker model is crucial for designing vehicles that can effectively navigate through various forest environments without getting stuck or causing excessive damage to the terrain.

Firebreak Creation

Creating firebreaks is a critical strategy in managing wildfires. In this simulation, ploughed firebreaks are created by the vehicle as it moves through the forest. These firebreaks serve to reduce fuel availability and slow down or stop the spread of the fire. The effectiveness of these firebreaks depends on their width, depth, and placement relative to the wind direction and slope of the terrain.

By simulating different scenarios, one can optimize the design of firebreaks for maximum efficiency in containing wildfires.

Rollover Dynamics

As the water tank empties during firefighting operations, the center of gravity of the vehicle shifts. This change can affect its stability and increase the risk of rollover. The simulation takes into account the dynamic nature of these changes by continuously recalculating the forces acting on the vehicle’s body. Rigid-body simulations are used to predict whether the vehicle will remain upright or tip over under various conditions.

Understanding rollover dynamics is essential for ensuring the safety and effectiveness of firefighting operations.

Frequently asked questions

Try it live

Everything above runs in your browser — open Forest Fire All-Terrain Vehicle: Traction, Slope Stability and Firebreak Lab and change the parameters while it is running. Nothing is installed, nothing is uploaded, the whole model lives in one tab.