Hamiltonian's Principle in Aero Elasticity — Lesson 4

This lesson covers the concepts of Hamilton's Principle and Lagrange's Equation in the context of aeroelastic problems. It explains how these principles are used to develop equations of motion for deformable bodies and rigid bodies. The lesson also discusses the concept of kinetic energy, potential energy, and non-conservative forces. It further elaborates on the principle of least action and how it is used in variational calculus. The lesson provides a detailed explanation of how to derive Lagrange's equation from Hamilton's principle and how to use these equations to solve aeroelastic problems.

Video Highlights

00:49 - Explanation of the polynomial constraint and the concept of virtual displacement.
09:25 - Explanation of the concept of energy virtual work done.
15:52 - Discussion on the concept of D' Alembert's principle and its application in dynamics.
28:08 - Discussion on the concept of Hamilton's principle and its application in dynamics.
42:58 - Explanation of the concept of Lagrange's equation and its derivation from Hamilton's principle.

Key Takeaways

- Hamilton's Principle and Lagrange's Equation are fundamental concepts used to develop equations of motion for both deformable and rigid bodies.
- Kinetic energy is a function of generalized coordinates and their time derivatives, while potential energy is a function of position.
- The principle of least action, a concept in variational calculus, states that the variation of the integral of the Lagrangian from one time to another is zero.
- These principles are extensively used in aeroelastic problems to derive the equations of motion.