Elevator Control Policy Design for a 4-Stop Building (Basement + 3 Floors)

Context

Design the control policy for a single elevator serving a 4-stop residential building: Basement (B), Floors 1–3. Assume traditional hall calls with direction buttons and standard in-cab destination buttons (no advanced destination dispatch, unless you choose to propose it as an optional variant).

Tasks

1. Objectives
   • Define primary and secondary objectives (e.g., minimize average wait time, ride time, bound tail latencies, avoid starvation, handle peak traffic patterns).
2. Constraints
   • Enumerate operational and safety constraints: capacity, timing (door open/close, dwell, floor-to-floor travel), weight limits, door sensors, and call semantics.
3. Inputs and State
   • List inputs (hall and cab calls with direction), sensors (position, door state, load), and internal state required for control.
4. Scheduling Policy
   • Propose concrete scheduling strategies suitable for this building, such as:
     • Directional SCAN/LOOK (collective control).
     • Destination grouping (if available) or approximate grouping.
     • Priority rules for basement during peak periods.
     • Anti-starvation and capacity-aware rules.
   • Include tie-breaking and idle parking behavior.
5. Data Structures and Control Logic
   • Specify data structures to store requests and state.
   • Provide a simple state machine and high-level pseudocode for the controller.
6. Simulation Plan
   • Outline a discrete-event simulation to compare policies under varying arrival distributions (uniform/off-peak, morning up-peak, evening down-peak, bursty).
   • Define parameters (travel/door times, capacity) and metrics (mean wait, 95th percentile wait, ride time, stops, reversals, fairness/starvation).
   • Describe experiment design, validation checks, and sensitivity analysis.