Multibay unit-load pre-marshalling problem instances

This dataset provides instances for experiments of the multibay unit-load pre-marshalling problem. For each experiment, we provide the instances as JSON-files. The folder exp_instances_tier_1 includes 27720 instances with one tier. The folder exp_instances_tier_2 includes 27720 instances with two tiers. The JSON-files contain the following information: warehouse_layout: Number of bays arranged in a square. bay_layout: Size of each bay. fill_level: Share of occupied slots in the warehouse. max_priority: Number of priority classes. seed: Seed used to generate the instance. access_directions: Allowed access directions. warehouse_state: Priority class for each slot defined by x, y, and z coordinates. Priority class zero corresponds to an empty slot. access_points: Access points in the warehouse in front of each bay. Each access point is located by x and y coordinates. robot_positions: Randomly generated initial positions for robots defined by x and y coordinates.