Autonomous omnidirectional vehicles that combine redundant holonomic kinematics, ROS 2/micro-ROS implementation, and simulation-to-real validation remain limited in the literature. This paper presents an eight-wheel Mecanum autonomous mobile robot for campus navigation in environments shared with pedestrians. The work formulates forward and inverse kinematics for the redundant eight-wheel topology and implements a distributed architecture in which ROS 2 handles high-level navigation and micro-ROS connects ESP32-based wheel interfaces. The platform integrates LiDAR, stereo vision, inertial, encoder, and ultrasonic sensing within a closed-loop navigation stack. Validation was conducted through Gazebo simulation and physical experiments using an out-and-back navigation protocol. In the physical platform, 91 of 100 missions were completed without safety interruptions, with pose-accuracy success rates of 96% for outbound legs and 81% for return legs under $e_p<1.5\mathrm{m}$ and $|e_{\theta }|<{15}^{\circ }$. Median errors at the intermediate waypoint were $0.64\mathrm{m}$, $0.191\mathrm{m}$, and ${17}^{\circ }$, while final-pose medians after return were $1.016\mathrm{m}$, $0.573\mathrm{m}$, and ${28.5}^{\circ }$. These results provide a quantitative baseline for campus-scale redundant Mecanum navigation and identify heading recovery as the main limitation.