( Test 1D contact spring.
  The right node of the bar moves with velocity -1. to the left,
  so that because of the contact spring the left node should
  move with velocity -0.5 )

echo -no
number_of_space_dimensions 1
materi_velocity
materi_velocity_integrated
materi_stress
end_initia

options_mesh -fixed_in_space
options_convection -no

node  1  0.
node  2  0.
node  3  1.
element 1  -bar2 2 3
element 2  -contactspring 1 2

element_group 1  0
element_group 2  1

group_type 0  -materi
group_materi_elasti_young 0  1.0
group_materi_memory 0  -updated_without_rotation

group_type 1  -contactspring
group_contactspring_stiffness 1  1. 1.
group_contactspring_friction 1  1.e6
group_contactspring_direction 1 1. 0. 0.

bounda_unknown 0  -ra 1 -ra -velx
bounda_time    0  0.
bounda_unknown 2  -ra 3 -ra -velx
bounda_time    2  -1.

print_filter 1  -node_dof -all -velx -sigxx

control_timestep             10  1.e-3 1.e-3
(
control_print                10  -time_current -node_dof
)

target_item 1  -node_dof 2 -velx
target_value 1  -0.5 1.e-4
end_data
