Optimizing Work: Finding the Minimum Path in Non-Conservative Vector Fields

In summary, the conversation discusses finding the path that requires the least amount of work from point A to point B in a non-conservative vector field. The technique to solve this problem is the Calculus of Variations, where a Lagrangian is determined and the Euler Lagrange equations are solved. The Lagrangian in this case is set to 1, and the resulting ODE is solved numerically to find the path that minimizes energy and follows Newton's Second Law.
  • #1
goffinj
2
0
I was wondering, if you have a non-conservative vector field (so that the line integral of each path from point A to point B isn't the same) that represents some sort of force, then is there a method to find the path that requires the least amount of work from a designated point A to point B? Even if you can't calculate it exactly is there a numerical approximation for such a path? Thanks for any help or suggestions.
 
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  • #2
The technique you would use to solve this kind of problem is the Calculus of Variations. You just need to determine a Lagrangian and then solve the Euler Lagrange equations.
 
  • #3
What Lagrangian would you set up?

We want to find the path that minimizes W = integral F dot dr. How do you solve for a path?

I apologize for the sloppy notation; this is my first post and I'm not familiar with tricks to get the integral and dot product signs to show up.
 
  • #4
Just take your "Lagrangian" to be "1". That way minimizing the value will minimize the path length.
 
  • #5
There's an absurdly simple way to solve this problem.

For position x, vector field v is given by v(x). Solve

dx/dt = v(x)

where t is a parameter: x = x(t).

It's a system of ordinary differential equations, but such equations should be easy to solve numerically. The main problem is keeping the ODE-solver step size in a reasonable range.
 
  • #6
The path that takes the least energy, is the path that an actual particle will travel along (a result of minimum action principle) which is the path that abides Newton's Second Law, so it will solve the ODE:

[tex]\frac{d^{2}\vec{x}}{dt^{2}}=\vec{F}(\vec{x})[/tex]

(F being the vector field)
 

1. What is a "Minimum Path" in vector fields?

A minimum path in vector fields refers to the shortest path or trajectory between two points in a vector field. It is determined by the direction and magnitude of the vectors within the field, and the path that minimizes the overall energy or cost.

2. How are minimum paths calculated in vector fields?

Minimum paths in vector fields can be calculated using various mathematical techniques, such as gradient descent, dynamic programming, and graph search algorithms. These methods take into account the direction and magnitude of the vectors in the field to determine the path with the minimum cost.

3. What are the applications of minimum paths in vector fields?

Minimum paths in vector fields have applications in various fields, including computer graphics, robotics, and fluid dynamics. They can be used to optimize the movement of objects, plan efficient routes, and model the flow of fluids.

4. Can minimum paths in vector fields be affected by obstacles?

Yes, minimum paths in vector fields can be affected by obstacles. In the presence of obstacles, the path may need to deviate from the shortest distance to avoid collisions or minimize energy costs. This can be achieved by incorporating obstacle avoidance techniques into the calculation of the minimum path.

5. Are there any limitations to using minimum paths in vector fields?

One limitation of using minimum paths in vector fields is that they may not always represent the most optimal solution. Depending on the method used to calculate the path, there may be cases where a different path with a higher cost may actually be more efficient. Additionally, external factors such as changing environments or unpredictable obstacles can also affect the accuracy of minimum paths in vector fields.

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