【请教】adams函数bistop的参数含义

my_dear2002

bistop(x,x',x1,x2,k,e,cmax,d)
x：计算力的距离或角度变量
x'：距离或角度变量的一阶导数，也就是线速度或角速度
x1：x值的上限值
x2：x值的下限值
K：借助表面的刚度系数
e：描述力变化的系数，对于一个硬弹簧e>1，对于软性弹簧e在0～1之间
cmax ：最大阻尼系数
d：

这个函数的最后一个参数什么意思呢?我把函数的英文解释贴出来麻烦大家给看看什么意思呢

x The distance variable you want to use to compute the force. For example, if you want to use the x displacement of Marker 0201 with respect to 0301, then x is DX(0201,0301,0301).
The time derivative of x to BISTOP. For example, if x is DX(0201,0301,301) then is VX(0201,0301,0301,0301).
x1 The lower bound of x. If x is less than x1 ADAMS/Solver (C++) calculates a positive value for the force. The value of x1 must be less than the value of x2.
x2 The upper bound of x. If x is greater than x2 ADAMS/Solver (C++) calculates a negative value for the force. The value of x2 must be greater than the value of x1.
k A non-negative value that specifies the stiffness of the boundary surface interaction.
e A positive value that specifies the exponent of the force deformation characteristic. For a stiffening spring characteristic, e > 1.0. For a softening spring characteristic, 0 < e < 1.0.
cmax A non-negative variable that specifies the maximum damping coefficient.
d A positive real variable that specifies the penetration at which the full damping coefficient is applied.

yihuang200614

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