--- a
+++ b/Knee Extension Testing/props_PatellarTendon.inp
@@ -0,0 +1,90 @@
+*MEMBRANE SECTION, ELSET=PAT_LIG-2D, MATERIAL=TENDON_PAT_MAT
+1.0,
+*MATERIAL, NAME=TENDON_PAT_MAT
+** material definitions have STRESS (MPa) vs STRAIN (%)
+*HYPERELASTIC, POISSON=0.498, TEST DATA INPUT, VAN DER WAALS, BETA=0
+**
+*UNIAXIAL TEST DATA
+0.0062,  0.07
+0.0144,  0.15
+0.0288, 0.25
+0.0504, 0.36
+0.0728, 0.48
+0.1003, 0.67
+0.1185, 0.79
+*DENSITY			
+5E-8,
+**
+*DAMPING, ALPHA=100.
+**
+*MASS, ELSET=PAT_LIG_MASS
+1E-5
+**************PL DEFINITION***********************************
+*PARAMETER
+** PL_L=the nominal FIBERament length(mm)
+PL_L=61.6
+** PL_eref=the reference strain (+)=added slack, (-)=initial force
+PL_eref=0.0
+** PL_k=the nominal stiffness (N/unit strain); for (N/mm) divide FIBER_k by FIBER_L
+PL_k = 50000.0
+** PL_num_sp_par=number of springs in parallel representing whole FIBERament
+PL_num_sp_par = 6.0
+PL_num_sp_ser = 16.0
+**
+k_ratio=50000.0/PL_k
+PL_sp_L = PL_L/PL_num_sp_ser
+**
+*PARAMETER
+PL_Lref=PL_sp_L
+PL_L0=PL_Lref/(PL_eref+1)
+**
+PL_d0=(PL_Lref-PL_L0)/PL_num_sp_ser
+PL_d2=((PL_Lref+0.02*PL_Lref)-PL_L0)/PL_num_sp_ser
+PL_d4=((PL_Lref+0.04*PL_Lref)-PL_L0)/PL_num_sp_ser
+PL_d6=((PL_Lref+0.06*PL_Lref)-PL_L0)/PL_num_sp_ser
+PL_d10=((PL_Lref+0.1*PL_Lref)-PL_L0)/PL_num_sp_ser
+PL_d20=((PL_Lref+0.2*PL_Lref)-PL_L0)/PL_num_sp_ser
+PL_d100=((PL_Lref+1.0*PL_Lref)-PL_L0)/PL_num_sp_ser
+PL_d200=((PL_Lref+2.0*PL_Lref)-PL_L0)/PL_num_sp_ser
+**
+PL_f0=0.0*k_ratio
+PL_f2=420.0/(PL_num_sp_par*PL_num_sp_ser*k_ratio)
+PL_f4=830.0/(PL_num_sp_par*PL_num_sp_ser*k_ratio)
+PL_f6=1500.0/(PL_num_sp_par*PL_num_sp_ser*k_ratio)
+PL_f10=3600.0/(PL_num_sp_par*PL_num_sp_ser*k_ratio)
+PL_f20=9000.0/(PL_num_sp_par*PL_num_sp_ser*k_ratio)
+PL_f100=50000.0/(PL_num_sp_par*PL_num_sp_ser*k_ratio)
+PL_f200=100000.0/(PL_num_sp_par*PL_num_sp_ser*k_ratio)
+**
+*SPRING, NONLINEAR, ELSET=PAT_LIG-SP
+
+0.0 , -<PL_d100>
+<PL_f0> , <PL_d0>
+<PL_f2> , <PL_d2>
+<PL_f4> , <PL_d4>
+<PL_f6> , <PL_d6>
+<PL_f10> , <PL_d10>
+<PL_f20> , <PL_d20>
+<PL_f100> , <PL_d100>
+<PL_f200> , <PL_d200>
+**
+*SURFACE, NAME=SURF-PAT_LIG, MAX RATIO=0.8
+PAT_LIG-2D, SPOS
+**
+*NODE
+290, 25, 15, -50
+291, 25, 15, -53
+**
+*ORIENTATION, DEFINITION=NODES, NAME=PAT_TEND_ORI
+290, 2900000, 291 
+*ELEMENT, TYPE=CONN3D2, ELSET=PAT_TEND_PULL
+290, 291, 290
+**
+*CONNECTOR SECTION, ELSET=PAT_TEND_PULL
+TRANSLATOR,
+PAT_TEND_ORI,
+**
+*MPC
+BEAM, TEND_PAT_ATTACH, 3900000
+BEAM, TEND_TIB_ATTACH, 290
+BEAM, 291, 2900000
\ No newline at end of file