Optimizing Drone Deliveries: A Linear Algebra Problem in Real Life
Problem Statement:
In the age of automation and rapid delivery, drones are becoming a vital part of last-mile logistics. Suppose we have a delivery drone that can:
- Carry up to 5 kilograms of packages per trip, and
- Complete 3 deliveries before it needs to return for charging.
Each delivery involves exactly one package, and packages are of two types:
- Type A: 1.5 kg
- Type B: 2.5 kg
The challenge:
What is the maximum number of 2.5 kg packages the drone can deliver in one trip while still making all 3 deliveries without exceeding the 5 kg weight limit?
Step-by-Step Analysis
We are asked to maximize the number of heavier packages (2.5 kg) under the given constraints:
- The drone can carry 3 packages in total.
- The combined weight must not exceed 5 kg.
Letβs define variables:
- Let x be the number of 2.5 kg packages (Type B).
- Let y be the number of 1.5 kg packages (Type A).
Constraints:
- x + y = 3 β Because the drone must carry exactly 3 packages.
- 2.5x + 1.5y β€ 5 β The total weight must be β€ 5 kg.
- x, y β₯ 0 and must be integers (canβt carry half a package).
Solving the Equations
Substitute the first constraint into the second:
Since:
y = 3 β x
Plug into the weight equation:
2.5x + 1.5(3 β x) β€ 5
2.5x + 4.5 β 1.5x β€ 5
(2.5 β 1.5)x + 4.5 β€ 5
x + 4.5 β€ 5
x β€ 0.5
But x must be a whole number, so the maximum integer value satisfying this is:
x = 0
Final Answer:
- Maximum number of 2.5 kg packages = 0
So the drone cannot deliver even one 2.5 kg package if it must make all 3 deliveries and stay under the 5 kg limit.
Letβs check:
- 3 packages Γ 1.5 kg = 4.5 kg
- If we try 1 package of 2.5 kg + 2 Γ 1.5 kg = 5.5 kg
Insight & Real-Life Implication
This problem illustrates a real-world constraint-based optimization, often encountered in logistics, supply chain, and robotics. It combines:
- Algebra (equation solving),
- Inequalities (weight limits), and
- Integer programming (discrete decision variables).
It also highlights:
- How heavier items reduce total quantity, and
- Why companies must consider package weight classes for route planning.
Extension: What Ifβ¦
Q: What if the drone could make only 2 deliveries instead of 3?
New constraint: x + y = 2
Repeat the same process:
Substitute y = 2 β x in the weight constraint:
2.5x + 1.5(2 β x) β€ 5
2.5x + 3 β 1.5x β€ 5
x + 3 β€ 5 β x β€ 2
x = 2 is valid!
Total weight: 2 Γ 2.5 = 5 kg β Exactly fits.
Answer: It could carry 2 heavy packages in that case.
Conclusion
The Delivery Drone Optimization problem is a compact example of how math governs modern-day technology. By modeling constraints using algebra, we can make better, data-driven decisions in logistics.