Real-Time Optimal Scheduling of a Group of Elevators in a Multi-Story Robotic Fully-Automated Parking Structure

This study presents a simulation-based feasibility study for development of a real-time scheduling algorithm for a multi-story and fully-automated parking structure with a group of elevators. Each elevator is conceived to carry one vehicle (car, small truck, SUV or minivan) between floors. Elevator count for a specific parking structure with number of floors in the range of 4 to 20, and 400 parking spaces on each floor is derived under an assumed customer arrival rate and mean service rate using the waiting line model of the queuing theory. A scheduling algorithm based on nested partitions and genetic algorithm is evaluated through the simulation study. The simulation environment models the mean arrival time of customers and elevator dynamics during morning rush hours for busy urban commercial multi-storied parking structures. Performance evaluation of the implemented elevator scheduling system was realized using the MATLAB environment. Performance metrics of mean customer waiting and elevator service times, and maximum customer waiting time were monitored. Simulation results demonstrate that the proposed design facilitates acceptable customer waiting and service times with good utilization rates for the elevators.