[physics.continuum_mechanics] Wrong plot obtained for shear force diagram

[Abhinav R]

Hello

I was trying out a beam problem and came upon this bug:

On drawing the beam and plotting the shear force diagram, the result I get is:

However, the correct plot would have been:

There are two issues with this, The support reaction are not being calculated correctly, The contribution of force due to the ramp load is wrong.

I have opened an issue relating to the ramp load. I request you to take a look at it and let me know if this is an actual bug in the code.

Here is the link: https://github.com/sympy/sympy/issues/25016

The code I used to get the Sympy plot results is:

from sympy.physics.continuum_mechanics.beam import Beam

from sympy import symbols

E, I = symbols('E, I')

b = Beam(6, E, I)

b.apply_support(0, "pin")

b.apply_support(3, "roller")

b.apply_load(4, 3, 0, end=6)

b.apply_load(4, 0, 1, end=3)

R_0, R_3 = symbols('R_0, R_3')

b.solve_for_reaction_loads(R_0, R_3)

p = b.draw()

p.show()

b.plot_shear_force()

Thanks and Regards,
Abhinav Cillanki