Bin Packing with Gurobi

This web app demonstrates optimized bin packing, a powerful algorithmic technique used to efficiently pack items of different sizes and shapes into a fixed space. We used Gurobi to find the optimal solution that minimizes wasted space and maximize the utilization of the van up to 86.4%. How well can you do the job?

What is Bin Packing?

Bin packing is a fundamental problem in computer science and optimization, often used in real-world scenarios like shipping, packaging, or resource allocation. Imagine you have a set of items, each with a specific size, and you want to pack them into a limited number of containers (bins) with fixed capacities. The goal is to find the most efficient way to fill the items into the bins, minimizing wasted space and using as few bins as possible.

Let’s use a simple analogy to explain bin packing in layperson’s terms: Imagine you have different sizes of cookies (items) and lunch boxes (bins) of various sizes. Your task is to pack the cookies into the lunch boxes so that you use as few lunch boxes as possible while ensuring that all cookies are intact.

You want to achieve two main objectives:

  1. Minimize the number of lunch boxes used: You want to save space, so try to fit as many cookies as possible into each lunch box.
  2. Avoid overfilling the lunch boxes: You must ensure that the total size of the cookies in each lunch box is at most its capacity. Otherwise, you risk damaging the cookies.

Let’s relate this to linear models and solvers like Gurobi: In more complex real-world scenarios, you might have many items and bins, making it challenging to find the best packing manually. This is where linear models and solvers like Gurobi come in handy. They are powerful tools using mathematical techniques to solve these packing problems efficiently.

Using linear models, you can mathematically express the problem’s constraints, like ensuring the sum of cookie sizes in each lunch box doesn’t exceed its capacity. Then, the solver (Gurobi, in this case) takes these constraints and finds the best solution, determining which cookies should go into which lunch boxes to minimize waste and use the fewest boxes.

By utilizing these tools, you can tackle real-world bin packing challenges with large numbers of items and bins, making the process more efficient and optimized.