How can you determine the optimal number of vehicles for vehicle routing and scheduling?

1 Demand analysis

The first step in determining the optimal number of vehicles is to analyze the demand for your products or services. You need to estimate how many customers you have, where they are located, what they order, and when they want to receive their deliveries. You can use historical data, forecasts, surveys, or other sources of information to obtain these details. Demand analysis will help you understand the size, frequency, and variability of your orders, as well as the spatial and temporal distribution of your customers.

2 Capacity calculation

The next step is to calculate the capacity of your vehicles and your depot. You need to consider how much space, weight, and volume each vehicle can carry, as well as how many vehicles you have available and how long they can operate. You also need to account for the capacity of your depot, where you store, load, and unload your goods. Capacity calculation will help you determine how many orders each vehicle can handle, as well as how many trips and stops it needs to make.

4 Time window optimization

The fourth step is to optimize the time windows for your deliveries. You need to balance the preferences and constraints of your customers and your vehicles. You need to respect the deadlines, availability, and service level agreements of your customers, as well as the working hours, breaks, and rest periods of your drivers. You also need to account for the uncertainty and variability of the travel time, demand, and service time. Time window optimization will help you improve the punctuality, reliability, and satisfaction of your VRS.

5 Vehicle assignment

The fifth step is to assign the vehicles to the orders and the routes. You need to use a suitable method or algorithm to find the best way to allocate your resources and minimize your costs. You can use mathematical models, heuristic rules, simulation techniques, or artificial intelligence methods to solve this complex and dynamic problem. You also need to consider the compatibility, flexibility, and adaptability of your vehicles and your orders. Vehicle assignment will help you achieve the optimal number of vehicles for your VRS.

6 Performance evaluation

The final step is to evaluate the performance of your VRS solution. You need to use appropriate metrics and indicators to measure the effectiveness, efficiency, and quality of your VRS. You can use quantitative measures, such as total distance, time, cost, and emissions, or qualitative measures, such as customer feedback, driver satisfaction, and safety. You also need to compare your results with your objectives, benchmarks, and competitors. Performance evaluation will help you identify the strengths, weaknesses, and opportunities for improvement of your VRS.