Constrained Local Search for Last-Mile Routing

Last-mile routing refers to the final step in a supply chain, delivering packages from depot station homes of customers. At level single van driver, task is traveling salesman problem. But choice route may be constrained by warehouse sorting operations, van-loading processes, driver preferences, and other considerations rather than straightforward minimization tour length. We propose simple efficient penalty-based local search algorithm for optimization presence such constraints, adopting technique developed Helsgaun extend Lin–Kernighan–Helsgaun problem general vehicle problems. apply his handle combinations constraints obtained an analysis historical data, enforcing properties that are desired high-quality solutions. Our code available under open-source Massachusetts Institute Technology license. An earlier version received $100,000 top prize Amazon Last Mile Routing Research Challenge organized 2021.