Free Body Diagram

In order to build up my model some boundary conditions need to be defined. For this a free body diagram is helpful. With it it’s possible to visualise what is interacting with my target body.

Free Body Diagram Train Seat
Free Body Diagram Train Seat

With this in mind we have two fixed supports that constrain (X, Y, Z and fixation null torque in all directions Mx, My and Mz).

I will continue more in-depth since im am curious regarding tubular meshing and to actually know if the seat can take a 120Kg weight on top.

Will it hold?

My today’s train trip is being quite interesting. As someone sat on a seat it wobbled. It made me think “how much would it hold”. Well, I enjoyed the seat design with it’s tubular shape and table attached to it.

Train seat
Train seat

This made me think also. How would I model this?

I have a few inputs/assumptions I already can imagine:

  • Assuming a 120Kg (more or less 250 pounds) person
  • Isotropic behaviour structural steel
  • Perfect welding connections (I know I know but it’s just a rough analysis)

Maybe these boundary conditions, hold the seat in place. I will also assume only one seat is present instead of the hole bundle.

Boundary condition of seat
Boundary condition of seat

On my next post I will follow up on the model building.