“Chasing Vertices: A Time-Bound Pursuit Problem in a Square”

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Homework Statement
Consider a square with a side length of 1 meter. At each vertex of the square, there is a point. Each point moves at a constant speed of 1 meter per second, and the direction of movement is always towards the next vertex. In other words, point 1 moves towards point 2, point 2 moves towards point 3, point 3 moves towards point 4, and point 4 moves towards point 1. How long will it take for all the points to meet at the center?
Relevant Equations
Whatever equations work. Was given to us while learning about vectors.
I know that the velocities are perpendicular to each other and that they are moving in a spiral and that they will meet in the centre of the square. From that, I know the displacement of the point but I do not know how to get the time, since the velocity is always changing direction. Could I somehow take the average velocity?
 
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The radial component (towards the center) of each velocity has the same magnitude during the spiraling towards the center.
 
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nasu said:
The radial component (towards the center) of each velocity has the same magnitude during the spiraling towrads the center.
The implication is that the square remains a square as it shrinks. (As was already clear).

The radial component is independent of scale. So it is constant over time.
 
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jansons said:
since the velocity is always changing direction
Two mice are one meter apart. By how much is that distance reduced in a time interval of ##dt## ? :wink:

[edit]
This one is known as the mice problem. See also Radiodrome

##\ ##
 
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1. What is the main objective of the study?

The main objective of the study is to find the optimal strategy for a time-bound pursuit problem in a square, where a pursuer and evader move along the edges of the square and the pursuer must catch the evader within a given time limit.

2. How is the problem formulated?

The problem is formulated as a mathematical model, where the positions and velocities of the pursuer and evader are represented as functions of time. The objective is to find the optimal control inputs for the pursuer that will lead to the capture of the evader within the time limit.

3. What are the key assumptions made in the study?

The study assumes that the pursuer and evader have perfect knowledge of their positions and velocities, and that they can accelerate and decelerate instantaneously. It also assumes that the evader moves in a straight line along the edges of the square and that the pursuer can only move along the edges.

4. How is the problem solved?

The problem is solved using the Pontryagin's maximum principle, which is a mathematical tool for solving optimal control problems. This involves finding the Hamiltonian function, which is a combination of the system dynamics and the cost function, and then using it to derive the optimal control inputs for the pursuer.

5. What are the potential applications of this study?

This study has potential applications in various fields such as robotics, game theory, and military tactics. It can also be used to understand and improve strategies for pursuit and evasion scenarios in real-life situations, such as law enforcement or sports.

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