Dear LAMMPS users,
When I use the “fix smd command”, can I use a variable defined by “variable command” to give the value for R0 (the distance of end of spring from tether point).
Because in the previous period, I have used the “fix smd command” doing the constant velocity with the tether mode. Then in the next period, I want the spring can hold the force (but not a constant force), then I do the equilibrium for the system. So I need change the constant velocity to be zero, and redefine the R0 according to the distance between the tether point and the current instantaneous mass center of the fixed group. Therefore, I want the R0 can be a instantaneous value.
Dose anyone know whether it’s doable or not? If my way is not doable, is there any other way can realize my idea?
Your kind help would be most appreciated.
Sincerely
Yajie
Dear LAMMPS users,
When I use the "fix smd command", can I use a variable defined by "variable
command" to give the value for R0 (the distance of end of spring from tether
point).
Because in the previous period, I have used the "fix smd command" doing the
constant velocity with the tether mode. Then in the next period, I want the
spring can hold the force (but not a constant force), then I do the
equilibrium for the system. So I need change the constant velocity to be
zero, and redefine the R0 according to the distance between the tether point
and the current instantaneous mass center of the fixed group. Therefore, I
want the R0 can be a instantaneous value.
yajie,
the fix actually actually stores the current value of R0
in the output vector. it can be accessed via f_name[5]
with name being the ID of the fix smd instance.
cheers,
axel.