Reducing the Collision Damage Done to the Tips of Steel Needles during Integrated Piercing by Using Shape Optimization with Feature Selection

Table 1

Calculation example parameters of yarn tension.

Parameter	Value	Unit	Note
Ec	2.3 × 10^11	Pa	Modulus of elasticity
Dc	9 × 10^−4	mm	Fiber diameter
η	2 × 10^−2		Contact coefficient
k	3 × 10^3		Yarn number k
dned	1.1	mm	Needle bar diameter
dkj	2.3	mm	Distance between holes
dk	2.0	mm	Hole diameter
Lxj	5	mm	Adjacent yarn distance
C	2.7 × 10^−1	mm	Fabric buckling wave height
τ	1155		Wave height adjustment factor
h	0.5	mm	Fiber Z-direction elongation