Involute profile in autocad

[Evening]

I'm looking a highly accurate way to draw the involute. Any suggestion?
I'm using AutoCad 2004. In the past in AutoCad 12 I used a nice LISP program IMPORT-3D-POLY written by Tony Hotchkiss, 2003 program which has converted from Excell Spreadhseet the involute cordinates into polyline in Autocad. Right now when I try to do same in Acad 2004, i always have a message:

IMPORT-3D-POLY - Error: bad argument type: FILE nil

what's the problem?

The lsp program looks like this:

;;; Cadalyst April 2003 AutoLISP Solutions
;;; import-3d-poly.lsp imports x,y,z coordinates
;;; from Excel spreadsheet into AutoCAD.
;;; Program (c) Tony Hotchkiss, 2003
;;;
(defun err (s)
(if (= s "Function cancelled")
(princ "IMPORT-3D-POLY - cancelled: ")
(progn (princ "IMPORT-3D-POLY - Error: ")
(princ s)
(terpri)
) ;_ progn
) ; if
(resetting)
(princ "SYSTEM VARIABLES have been reset\n")
(princ)
) ; err
(defun setv (systvar newval)
(setq x (read (strcat systvar "1")))
(set x (getvar systvar))
(setvar systvar newval)
) ; setv
(defun setting ()
(setq oerr *error*)
(setq *error* err)
(setv "CMDECHO" 0)
(setv "BLIPMODE" 0)
) ; end of setting
(defun rsetv (systvar)
(setq x (read (strcat systvar "1")))
(setvar systvar (eval x))
) ; restv
(defun resetting ()
(rsetv "CMDECHO")
(rsetv "BLIPMODE")
(setq *error* oerr)
) ; end of resetting

(defun poly3D ()
(setq ptlist1 (get-ptlist))
(make-3dpolyline ptlist1)
) ;_ poly3D

(defun get-ptlist ()
(setq fn (getfiled "3D points file" "" "txt" 8)
f (open fn "r")
str (read-line f)
plist nil
) ;_ end of setq
(while (/= str EOF)
(setq str (read-line f))
(if str
(progn
(setq pt (get-pt str))
(setq plist (append plist (list pt)))
) ;_ end of progn
) ;_ end of if
) ;_ end of while
(setq f (close f))
plist
) ;_ get-ptlist

(defun get-pt (str1)
(setq comma (chr 44)
str2 ""
count 1
i 0
) ;_ end of setq
(repeat 2
(repeat (strlen str1)
(setq char (substr str1 (setq i (1+ i)) 1))
(if (/= char comma)
(setq str2 (strcat str2 char))
(progn
(if (= count 1)
(progn
(setq x (atof str2))
(setq str1 (substr str1 (1+ i)))
(setq i 0)
(setq count 2)
(setq str2 "")
) ;_ end of progn
(progn
(setq y (atof str2))
(setq str1 (substr str1 (1+ i)))
(setq z (atof str1))
) ;_ end of progn
) ;_ end of if
) ;_ end of progn
) ;_ end of if
) ;_ end of repeat
) ;_ end of repeat
(setq pt (list x y z))
) ;_ end of get-pt

(defun make-3dpolyline (ptlist)
(entmake (list '(0 . "POLYLINE")
'(100 . "AcDbEntity")
'(100 . "AcDb3dPolyline")
'(70 . 8)
) ;_ list
) ;_ entmake
(repeat (length ptlist)
(setq pt (car ptlist)
ptlist (cdr ptlist)
) ;_ setq
(entmake (list '(0 . "VERTEX")
'(100 . "AcDb3dPolylineVertex")
(cons 10 pt)
'(70 . 32)
) ;_ list
) ;_ entmake
) ;_ repeat
(entmake '((0 . "SEQEND")))
) ;_ make-3dpolyline

(defun cl3 ()
(setting)
(poly3D)
(resetting)
(princ)
) ;_ cl3

(prompt "Enter PL3 to start")

 

[CarlAK]

As far as I can tell the routine you posted imports 3d points from a text file, then creates a 3dpolyline through these points. So I assume you are doing the involute calculations in Excel, saving the points to a text file, then you run the routine and select the text file. At what point in running the routine do you get the error message?

If you have the point coordinates (in the format x1,y1,z1) in a text file or in a column in Excel you don't need to use lisp to create the 3dpolyline. Just start the 3dpoly command, then copy and paste the point data to the command line.

In a quick search I found a lisp to draw involute/gear, you might see if this does the trick.

http://www.xanadu.cz/en/download.asp?file=truegear&sort=

 

[Evening]

yes, i have a txt file i made from excell spreadsheet, with x,y,z coordinates.
NO, i can't use the command line to enter the coordinates, becasue i have more then 1000 points with cordinates, so the lisp program cant help me only.
I can load the lisp program in Autocad succesfully.
When i start it running with entering PL3 in command line, the window appers to choose the file I'm loading the coordinates from.
I can choose the file, and then the error occurs:

IMPORT-3D-POLY - Error: bad argument type: FILE nil

What's the problem?

 

[CarlAK]

I don't know what the problem is, I'll try it out when I get a chance.

Did you try to copy and paste the text data? I didn't sugest "entering" the points in the command line. I have done this before in 1 step for close to 100 points, perhaps it will work with more than 1000. Or you can paste a few groups of 100's at a time.

 

[Evening]

I'm not sure why didn['t work yesterday, but i tried to open a new empty cad file, and this time succeeded. Loaidng the Txt file with Lisp command PL3, all 1000 points were connected into the polyline.