Mechanical Boundary condition application

Hello,
Video was created using
https://github.com/schrummy14/LIGGGHTS_Flexible_Fibers

You select which particles are bonded by atom type
So if you have a system that has non-bonded particle, bonded particles, and geometry, you would start with
atom_style hybrid granular bond/gran n_bondtypes 1 bonds_per_atom 6
This gives you a single bond type

Create a domain with your 3 atom types
create_box 3 domain

Then declare a granular bond
bond_style gran

Add your bond coefficients (See the documentation for what each value represents)
bond_coeff 1 1.0 0.0 1e9 5e8 1 0.1 1 1.0e32 1.0e32

Then create your two particle templates
for the non-bonded particle, simply use the normal particletemplate/sphere
fix pts1 all particletemplate/sphere 3571927 atom_type 2 density constant 8.526821e+01 radius constant 1.368261e-02

Then for the bonded particle, do the following
fix pts2 all particletemplate/multiplespheres 6931453 atom_type 1 density constant 2.317055e+02 nspheres 4 ntry 100000 spheres &
5.865102e-03 2.287433e-03 0.000000e+00 5.865102e-03 &
1.718638e-02 2.287433e-03 0.000000e+00 5.865102e-03 &
2.850765e-02 2.287433e-03 0.000000e+00 5.865102e-03 &
3.982893e-02 2.287433e-03 0.000000e+00 5.865102e-03 &
bonded yes

Create the distribution as normal. The last step is to insert the particles. Unfortunately, you cannot do dynamic insertion (on multiple cores). So you have to do the following.
fix ins all insert/pack seed 32452867 distributiontemplate pdd1 &
maxattempt 500000 insert_every once overlapcheck yes orientation random &
all_in yes vel constant 0.0 0.0 -0.0 region domain &
particles_in_region 500 ntry_mc 100000 check_dist_from_subdomain_border no

variable bond_skin equal 1.00001 # *${particle_diameter}

Bond the atoms together to form fibers
run 1
fix bondcr_1 all bond/create/gran 1 1 1 ${bond_skin} 1 6 doNorm yes #every itype jtype cutoff btype newperts
run 1
fix_modify bondcr_1 every 0 #do not create new bonds after this line
run 1

The doNorm flag allows you to be very creative of the fiber template and not need to worry about it bonding with things it shouldn't.

Hello,
the bond package is NOT part of the public release. You will need to use the repository that I linked. Once you have the repository downloaded, you simply compile it by issuing the command make auto.