How Do You Model a Horizontal Double Pendulum with External Forces?

[nyknicks012]

I'm working on determining the differential equations governing two linked bars that rotate around a fixed pivot (located at the end of one of the bars). Something like a double pendulum but rotating in the horizontal plane so gravity is not an issue. There are applied external forces at the end of each bar (2 bars = 2 forces). I tried working my way through using examples of a double pendulum I had found online, but the solution I get does not give intuitive results when simulated in matlab. Any help or link to a helpful site would be greatly appreciated.

Thanks again!

 

[berkeman]

I'm working on determining the differential equations governing two linked bars that rotate around a fixed pivot (located at the end of one of the bars). Something like a double pendulum but rotating in the horizontal plane so gravity is not an issue. There are applied external forces at the end of each bar (2 bars = 2 forces). I tried working my way through using examples of a double pendulum I had found online, but the solution I get does not give intuitive results when simulated in matlab. Any help or link to a helpful site would be greatly appreciated.

Thanks again!

Welcome to the PF. What is the context of this project? Is it an artistic project, or some mechanism for manufacturing of something, etc?

Can you post a sketch, with coordinate axes labeled, and show the forces and positions that are in your calculations? Can you post your attempt at the solutions so far, at least how you are trying to set up the DiffEqs?