Quantum annealing has been actively researched since D-Wave Systems produced the first commercial machine in 2011. Controlling a large fleet of automated guided vehicles is one of the real-world applications utilizing quantum annealing. In this study, we propose a formulation to control the traveling routes to minimize the travel time. We validate our formulation through simulation in a virtual plant and authenticate the effectiveness for faster distribution compared to a greedy algorithm that does not consider the overall detour distance. Furthermore, we utilize reverse annealing to maximize the advantage of the D-Wave's quantum annealer. Starting from relatively good solutions obtained by a fast greedy algorithm, reverse annealing searches for better solutions around them. Our reverse annealing method improves the performance compared to standard quantum annealing alone and performs up to 10 times faster than a commercial classical solver, Gurobi. This study extends a use of optimization with general problem solvers in the application of multi-AGV systems and reveals the potential of reverse annealing as an optimizer.
Quantum annealing has been actively researched since D-Wave Systems produced the first commercial machine in 2011. Controlling a large fleet of automated guided vehicles is one of the real-world applications utilizing quantum annealing. In this study, we propose a formulation to control the traveling routes to minimize the travel time. We validate our formulation through simulation in a virtual plant and authenticate the effectiveness for faster distribution compared to a greedy algorithm that does not consider the overall detour distance. Furthermore, we utilize reverse annealing to maximize the advantage of the D-Wave's quantum annealer. Starting from relatively good solutions obtained by a fast greedy algorithm, reverse annealing searches for better solutions around them. Our reverse annealing method improves the performance compared to standard quantum annealing alone and performs up to 10 times faster than a commercial classical solver, Gurobi. This study extends a use of optimization with general problem solvers in the application of multi-AGV systems and reveals the potential of reverse annealing as an optimizer.
Improving the efficiency, safety, and speed of large-scale Automated Guided Vehicle (AGV) systems is crucial for enhancing the productivity of logistics warehouses. Recent advancements in quantum annealing devices have demonstrated the potential to optimize AGV routing effectively. However, applying quantum annealing to complex and large-scale AGV routing problems remains challenging due to insufficient consideration of operational constraints and the limited number of qubits available in current quantum annealers. To address these challenges, this study proposes a new formulation for large-scale AGV routing by introducing a priority constant to reduce delays caused by constraint violations. Additionally, we develop a system architecture that employs multiple FPGAs to accelerate Simulated Quantum Annealing (SQA), thereby overcoming the computational inefficiencies of classical SQA implementations. The proposed architecture is designed to solve large-scale optimization problems involving tens of thousands of variables. Each FPGA board can process problems with up to 50,176 variables, and a five-FPGA parallel configuration achieves significantly faster processing speeds. The performance of the proposed system is validated using a commercial AGV Operating System (AOS), including experiments with real AGVs in a small-scale environment and simulations involving up to 1,000 AGVs. Experimental results demonstrate that the proposed SQA accelerator achieves faster processing speeds and higher-quality solutions compared to existing SQA solvers, confirming its effectiveness for large-scale AGV route optimization.
Enhancing the efficiency, safety, and speed of large-scale Automated Guided Vehicle (AGV) systems is critical to increasing the productivity of logistics warehouses. Studies using the latest quantum annealers such as "D-Wave Advantage" with over 5000 qubits have shown the potential of quantum annealing (QA) to rapidly optimize AGV routing. However, applying QA to complex and large-scale AGV routing problems is a challenging task due to insufficient consideration of intricate operational conditions, and also due to the insufficient number of qubits in quantum annealers. This paper proposes a refined combinatorial optimization problem that minimizes the total travel time of thousands of AGVs while enhancing safety and efficiency by avoiding collisions. To solve such large-scale optimization problems with thousands of variables, we also propose a novel system architecture containing a Simulated Quantum Annealing (SQA) accelerator using multiple FPGAs. The proposed SQA accelerator is capable of processing problems with over 50,000 variables, which could be a few tens to several hundred times larger than the problems processed on the "D-Wave Advantage". It addresses multiple combinatorial optimization problems across multiple FPGAs concurrently while processing each problem in a high degree of parallelism. We demonstrate the accurate operation of the proposed SQA accelerator using a real-world large-scale AGV system with over 1000 AGVs. According to the experimental results, we observed faster processing speed and better quality results over existing SQA solvers.
This study proposes a new approach to optimizing the routing of Automated Guided Vehicles (AGVs) in large-scale logistics warehouses using Quantum Annealing. As logistics operations grow, efficient AGV routing becomes critical for ensuring safety, reliability, and throughput, particularly in high-density environments. To address the complexity of real-world systems, we introduce an enhanced cost function that incorporates a real-time priority factor to improve both routing performance and operation safety. In this paper, we present a secure and computationally efficient candidate route generation method, along with an Optimization Problem Clustering technique that decomposes the large problem into smaller, tractable subproblems to reduce computational complexity. The proposed methods are designed to incorporate real-time operational data to ensure collision avoidance, maintain safe operations, and enhance routing efficiency in realistic large-scale warehouse environments. We validate the proposed methods using a state-of-the-art Quantum Annealing machine, benchmarking against both classical and quantum-inspired solvers. Integration with a commercial AGV Operating System (AOS) is demonstrated, enabling seamless connectivity with classical solvers via a local network and with Quantum Annealing and Quantum-inspired solvers via cloud infrastructure. Simulations involving 1000 AGVs show that the proposed route generation method reduces the number of optimization variables by an average of 96% for small-scale to medium-scale systems and 78% for large-scale systems, while also improving route quality. The clustering method reduces the maximum problem size to under 10,000 variables, enabling scalable and safe control of large AGV fleets. Furthermore, a complexity-based problem formulation reduces sampling time by approximately 28.2% compared to conventional size-based approaches for problems ranging from 1000 to 10,000 variables. These results demonstrate the practical viability of Quantum Annealing for managing large-scale AGV Operating Systems and underscore the potential of the proposed methods for advancing logistics optimization in real-world warehouse environments.
Vehicle routing refers to the generic problem of finding the optimal routes for a given fleet of vehicles with respect to a given measure of optimality and subject to a given set of constraints. Finding the exact solution to such a problem is NPhard. Hence, we often use heuristics to find feasible solutions. We use the DWave Hybrid solver to find a solution to the vehicle routing problem, and compare the time complexity of finding the solution as well as the quality of the solution found against a classical alternative, namely Gurobi v9.5. We observe that the quantum annealer shows better scaling with respect to size when compared to Gurobi.
We present annealing solutions for route optimization problems for unmanned aerial vehicles (UAVs), The route planning problem is a generalised version of the Travelling Salesman Problem which has many applications in logistics planning. Our annealing solutions combine classical algorithms with quantum/digital annealers specifically designed for quadratic optimization problems and shows improvements over generic traditional solvers such as Gurobi. We empirically test the solvability of our annealing solutions on both hand-crafted hard test cases as well as simulated ‘real-world’ examples of urban environments where the operations of the UAVs can be affected by the direction and intensity of wind, which is conditioned by the presence of buildings.
In this paper, we explore the potential for quantum annealing to solve realistic routing problems. We focus on two NP-Hard problems, including the Traveling Salesman Problem with Time Windows and the Capacitated Vehicle Routing Problem with Time Windows. We utilize D-Wave's Quantum Annealer and Constrained Quadratic Model (CQM) solver within a hybrid framework to solve these problems. We demonstrate that while the CQM solver effectively minimizes route costs, it struggles to maintain time window feasibility as the problem size increases. To address this limitation, we implement a heuristic method that fixes infeasible solutions through a series of swapping operations. Testing on benchmark instances shows our method achieves promising results with an average optimality gap of 3.86%.