This paper presents a method to determine the stability of off-road vehicles moving on rough terrain. The measures of stability are defined as the maximum speed and acceleration under which the vehicle does not slide or tip over. To compute these stability measures, we propose a quasi 3D analysis by decomposing the vehicle dynamics into three separate planes: the yaw, pitch, and roll planes. In each plane, we compute the set of admissible speeds and acceleration for the planar vehicle model, contact model, and ground force constraints. The intersection of the admissible sets provides the total range of feasible speeds and accelerations along the vehicle's path, from which we obtain the stability margins. Numerical results for a vehicle traversing a simulated terrain demonstrate the effectiveness of the approach.

Dynamic stability reflects the vehicle's ability to traverse uneven terrain at high speeds. It is determined from the set of admissible speeds and tangential accelerations of the center of mass along the path, subject to the ground force and geometric path constraints. This paper presents an analytical method for computing the stability margins of a planar all-wheel drive vehicle that accounts for soil parameters. It consists of mapping the ground force constraints to constraints on the vehicle's speeds and accelerations along the path. The boundaries of the set of admissible speeds and accelerations determine the static and dynamic stability margins, used to gage the traversability of the vehicle along the path. The first is the maximum feasible acceleration at zero speed, whereas the second is the maximum feasible speed. Both stability margins are demonstrated for a planar vehicle moving on a sinusoidal path.

Dynamic stability reflects the vehicle's ability to traverse uneven terrain at high speeds. It is determined from the set of admissible speeds and tangential accelerations of the center of mass along the path, subject to the ground force constraints and the geometric path constraints. This paper presents a geometric procedure for computing the set of admissible speeds and accelerations of a planar all-wheel drive vehicle. It first determines the boundaries of the set of resultant forces at the center of mass that satisfy the ground force constraints and the equations of motion along the path. This set is then mapped to the set of feasible speeds and accelerations along the path, from which the dynamic stability margin (DSM) is determined. A byproduct of this procedure is a static stability margin (SSM) that reflects the vehicle's ability to accelerate, or decelerate, at zero speed. Both stability margins are useful as cost measures for physics-based motion planning over rough terrain. The approach is demonstrated for a planar vehicle moving on a sinusoidal track

This paper describes a unified measure of stability of a Rocker Bogie vehicle that accounts for the tendency to slide, tipover, or lose contact with the ground considering both static equilibrium and dynamic effects. The measure of stability is computed by solving for the range of acceptable velocities and accelerations that satisfy a set of dynamic constraints. The maximum acceptable velocity serves as a dynamic stability measure, whereas the maximum acceptable acceleration at zero velocity serves as a static stability measure. The utility of the static and dynamic stability margins are demonstrated for both two dimensional and longitudinal quasi-3D motion in several examples.

This paper offers a unified measure for dynamic stability of off-road vehicles that accounts for the tendency to tipover, slide, or loose contact with ground during static equilibrium and in motion. The contacts between the vehicle and ground are assumed rigid, and all wheels are assumed active. The dynamic stability measure is determined by computing the range of velocity and acceleration of the vehicle's center of mass that satisfies a set of dynamics constraints. The upper velocity limit serves as a dynamic stability measure, whereas the acceleration limit at zero speed serves as a static stability measure. In this paper, we demonstrate the approach for a four-wheel drive planar vehicle.