Quantum Route Optimization With Delivery Time and Workload Constraints

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing vehicle routing problems using quantum computers lack sufficient constraints for generating realistic delivery plans, particularly in balancing vehicle workload and delivery times.

Innovation Solution

A combinatorial optimization device and method that adds first and second constraint terms to a cost function for specifying delivery time and balancing vehicle workload, utilizing a quantum computer for efficient route planning.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If quantum computing is used to solve vehicle routing problems, then computational efficiency is improved, but the constraints for generating realistic delivery plans are insufficient

Engineering Contradiction:
Improvecomputational efficiencyVSAvoidrealism of delivery plan
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

The patent transforms the vehicle routing problem into an Ising model by changing the parameter representation from classical routing variables to quantum spin variables. This parameter transformation enables the problem to be solved using quantum computing while incorporating multiple constraints (delivery time windows, vehicle capacity, workload balancing) through carefully designed Hamiltonian terms, thus achieving both computational efficiency and solution realism.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent introduces an intermediary classical control system that bridges the quantum computer and the vehicle routing problem. This control system prepares the cost function with appropriate constraint terms, interprets the quantum computing results, and translates them back into realistic delivery plans. The intermediary ensures that quantum computational efficiency is maintained while delivering practically viable routing solutions.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Reliability

If more constraint terms are added to the cost function, then the realism of delivery plan is improved, but the device complexity increases

Engineering Contradiction:
Improverealism of delivery planVSAvoidcost function complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent segments the complex constrained optimization problem into multiple independent constraint terms within the Hamiltonian function. Each constraint (delivery time windows, vehicle capacity, workload balancing) is represented as a separate term that can be independently formulated and tuned. This segmentation allows the system to manage complexity by addressing each constraint individually while maintaining the overall optimization framework.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The Ising model Hamiltonian serves as a universal framework that can accommodate multiple different types of constraints through a standardized mathematical form. The same quantum computing apparatus and optimization algorithm can handle various constraint types by simply modifying the Hamiltonian terms, providing multi-functionality without requiring separate systems for each constraint type.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Data Source

PatentUS20260105408A1Combinatorial optimization device, combinatorial optimization method, and computer program
Publication Date: 2026.04.16 PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO LTD
  • US20260105408A1 patent drawing
  • US20260105408A1 patent drawing
  • US20260105408A1 patent drawing

AI summary

According to the present invention, a more realistic and usable delivery plan is generated using a quantum computer. This combinatorial optimization device includes a control unit which is communicably connected to a quantum computer, wherein the control unit: adds a first constraint term specifying a time point relating to a delivery, and a second constraint term for leveling a workload of each vehicle to a cost function used to search for routes when a plurality of vehicles are to visit a plurality of delivery destinations; and causes the quantum computer to perform a quantum calculation of the cost function with the first constraint term and the second constraint term added thereto.