LISP for part rolling a angle by step

[bjyuen]

Hi~

I programed a LISP for a blank to roll one angle 0.9° step by step.( see the attachment LISP file)

Because position_pa command is a terminate action,so I use sd-call-cmds function in the LISP program.

When I ran the program to roll the part 0.9°，actually rolled angle was 51.566202°.

Does anybody could tell me why?

How can I  achieve my purpose to roll 0.9° step by step?

Thanks

Justin

This thread is inactive and closed by the PTC Community Management Team. If you would like to provide a reply and re-open this thread, please notify the moderator and reference the thread. You may also use "Start a topic" button to ask a new question. Please be sure to include what version of the PTC product you are using so another community member knowledgeable about your version may be able to assist.

[FriedhelmK]

Hello Justin,

I do not know much about Lisp programming,

but I see the cause in radiant.

1 rad = 180 ° / Pi = 57.295779513082320876798154814105°

° 0.9 = 51.566201561774088789118339332695° 

It revolves around 0.9 radiants and not around 0.9°

Best regards

Friedhelm

[bjyuen]

Friedhelm,

I know that 0.9rad equal 51.566202degree.

In the LISP using position_pa action have to set the angle in degree. So I set a variable angle_factor_deg.

Ran the LISP，you could see variable angle_factor_deg value was 0.9.

Justin

[ThomasKirkman]

A couple of tips  These will replace some of the work you did.

(sd-deg-to-rad angle)

(sd-rad-to-deg angle)

Lisp works in radians despite what units you have set.

So simply change the line from

:rotation_angle angle_factor_deg

to

:rotation_angle angle_factor_rad

regards

Tom

[ThomasKirkman]

you could also use this line.

:rotation_angle (sd-deg-to-rad .9)

[bjyuen]

Tom,

I know the function sd-deg-to-rad and sd-rad-to-deg.

In the LISP I defined a function g_test() that can be call to do roll part angle.

When push the button to call this function with " (sd-call-cmds (g_test))"，the result is the part roll 51.566202degree.

Change to call the function without sd-call-cmds, the ruslt is the part roll 0.9degree.

I can not understand why produce different results with sd-call-cmds or not.

Justin

[ThomasKirkman]

This is a question that I am not really qualified to answer. I am not sure what the issue is.

However, since you are defining local functions, you do not need to use sd-call-cmds to call those functions.

Regards

Tom

[bjyuen]

It could not achieve my purpose to roll a angle by step pushing the accept button in the dailog window.

Because the dailog window would be closed when I called the local functions without using sd-call-cmds.

Best regards.

Justin

[ThomasKirkman]

I went through the program again.

You are calling a modeling function (position_pa). If you call a modeling command like this, without placing it in the (sd-call-cmds) wrapper, it will run the command stop the current command.

    (g_test()

        (position_pa :part_assembly test_p

                    :rotate :axis :pt_dir fix_pnt1 (first dir1)

                    :rotation_angle angle_factor_deg

                    :done)

should be

    (g_test()

        (sd-call-cmds (position_pa :part_assembly test_p

                    :rotate :axis :pt_dir fix_pnt1 (first dir1)

                    :rotation_angle angle_factor_deg

                    :done))

Now you do not have to have the sd-call-cmds to call a local function.

I did some editing on the program for myself.

Regards

Tom

[ThomasKirkman]

A quick edit.

I used :minimum and :maximum for a not scaled value.  I re-wrote the input to check the angle to keep it in the range of -360 to 360.

Regards

Tom

[bjyuen]

As you suggestion I changed the code and then loaded the program.

Result was the same the part roll angle 51.566202° not 0.9°.

When you delete using sd-call-cmds function in the LISP program, load the program,you will find that the part roll 0.9°.

The question I really want to know is why get difference result to roll part using sd-call-cmds and not using it?

Best regards

Justin

[bjyuen]

I also found that using sd-call-cmds to call position_pa action you have to assigned :rotation_angle randians value. And not using sd-call-cmds you have to assigned :rotation_angel degree value.You did it the part would be rotated the same angle value.But I really not understand it.

Position_pa action's variable :rotation_angle should be a degree value assigned right?

Best regards

Justin

[ThomasKirkman · Accepted solution]

Justin

I am not 100% sure of the answer, I can give a best guess.  The calculations are done in lisp which requires radians.  Modeling takes a degree input and converts it to radians for calculations.

[bjyuen]

Maybe you are right,but I still do not understand it.

Best regards

Justin