各位大侠帮帮我吧 宏命令出问题

kurupikt

各位大侠，我按照一篇论文编辑了在链条铰链处施加铰接副的宏命令如下
variable create variable_name= ip integer_value= 3
    while condition= ( ip< 70)
      variable modify variable _name= ip integer _value= (eval ( ip+ 2) )
      constraint create joint Revolute &
      joint _name= (eval ("J _ "// ( ip/2+ 500) ) )&
      i_ marker _name= (eval ("_ "// ip ) )&
      j_ marker _name= (eval (" _ "// ( i p+ 1) ) )
      force create element_ like friction &
      friction _name = (eval ("F_ "//( ip//2+ 500) ) ) &
      mu _static = 0.12 &
      mu _dynamic = 0.1 &
      stiction _t ransition _velocity = 2 &
      max _stiction _deformation = 0.01 &
      effect = all &
      preload = on &
      reaction _force = on &
      bending _moment = on &
      friction _arm = 1.0 &
      pin _radius = 2.0 &
      friction _torque _preload = 0.0 &
      inactive _during _static = off
end
但是调试时的部分结果如下：
ERROR:  Error detected on line number 3, character 37 of the macro '.MACRO_1'.
ERROR:  Invalid input. Enter '='.
ERROR:  The command was not executed.
ERROR:  +2>>       variable modify variable _name= ip integer _value= (eval ( ip+ 2) )
ERROR:  Error detected on line number 5, character 18 of the macro '.MACRO_1'.
ERROR:  Invalid input. Enter '='.
ERROR:  The command was not executed.
ERROR:  +2&>       joint _name= (eval ("J _ "// ( ip/2+ 500) ) )&
ERROR:  Error detected on line number 8, character 33 of the macro '.MACRO_1'.
ERROR:  'like' is not a valid keyword. You may have misspelled
ERROR:  the keyword or you may be missing a continuation character(&)
ERROR:  on the previous line.
ERROR:  The command was not executed.
ERROR:  +2>>       force create element_ like friction &
请问我应该怎样修改 谢谢了