Research on route optimization model and hybrid algorithm for one-way circular microcirculation bus routes

To address the problems of difficult coordination between route mileage and service scale and low solution efficiency in the planning of urban one-way circular microcirculation bus routes, this paper constructs an objective function model of minimizing comprehensive mileage with penalty values, designs a hybrid solution strategy integrating ant colony and Dijkstra algorithms, and verifies the effectiveness of the model and algorithm through numerical examples. The model introduces a penalty value for the mileage of a single route, abandons the constraints of minimum trip distance and minimum number of stops visited, and retains only the maximum trip constraint, thereby achieving dynamic coordination between route mileage and service scale and improving the model’s scenario adaptability. On the solution side, a hybrid ant colony-Dijkstra algorithm with dynamic origin-destination selection is adopted, combined with a one-step-updated dynamic adjacency matrix and an automatic elimination strategy for bus stops along the route, significantly improving search efficiency. During the route construction process, a look-ahead judgment of the trip constraint is introduced, accurately calculating the accumulated mileage and remaining return distance based on the real-time updated adjacency matrix, ensuring that each route satisfies the maximum trip limit and eliminating infeasible trip solutions at the source. The numerical example results show that the model and algorithm can generate optimal solutions that satisfy the constraints, achieving 100% coverage of bus stops, stable convergence of the objective function, and excellent solution efficiency and practical applicability.