Dynamic Tip-over Stability of Ground-based Robots with Manipulators

This thesis presents a theoretical framework and derivations that provide the means for a direct comparison between various mobile robot tip-over stability measures popular in the literature. Here, the zero moment point (ZMP) stability measure was extended to account for ground slope, and modifications were made to the energy stability measure (ESM) to fix a limitation in the measure, as originally proposed. Numerical simulation results demonstrate that in contrast to what is frequently claimed, the ZMP measure is in fact sensitive to changes in the center of mass (COM) height under certain conditions. These simulations also demonstrate how COM height affects the force angle stability measure (FASM). Surface plots show how the stability changes with center of mass height as the manipulator arm rotates about the base. Moreover, the surface plots also reveal that the ESM loses sensitivity under certain conditions, unlike the ZMP and FASM.;To compliment these theoretical results, a human subject experiment was developed to explore which feedback modality would prove most useful to the human operator. The simulation was organized by six trial blocks: practice, no feedback, vision only, only auditory, only haptic, and all three feedback modalities. Differences in performance measures for various feedback modalities were presented. Two performance parameters were related to task block (feedback type) to a degree that was statistically significant. Subjects preferred visual feedback the most, auditory feedback next, and haptic feedback the least; however, the differences in means are not very large.;There are two major contributions in this thesis. The first is a theoretical framework, here focused on explosive ordnance disposal (EDO), for tip-over stability. The second is a human subject experiment demonstrating multiple possible techniques to relay tip-over stability information to the user.