Double pendulum as modulation in Kontakt KSP

Jamielufc11

Hi, I'm trying to use a double pendulum to modulate parameters within KSP

I've given it a go but my code is not giving me results. I was hoping to see some sort of wavy modulation

See code attached, any help would be gratefully appreciated, thanks in advance.

on init

declare ui_knob $Volume (0,1000000,1000000)




declare ~L1

~L1 := 100.00

declare ~L2


~L2 := 100.00
 


 declare ~M1

 ~M1 := 40.00

 declare ~M2

 ~M2 := 40.00
 


 declare ~A1

 ~A1 := 90.00

 declare ~A2

 ~A2 := 0.00
 


 declare ~A1V


 declare ~A2V


 declare ~A1A


 declare ~A2A
 


 ~A1V := ~A1A

 ~A2V := ~A2A

 ~A1 := ~A1V

 ~A2 := ~A2V
 


 declare ~G

 ~G := 9.81 
 
 


declare ~num1

 declare ~num2

 declare ~num3

 declare ~num4

 declare ~den

declare $test_int
end on

function pendulum

~A1V := ~A1A

~A2V := ~A2A

~A1 := ~A1V

~A2 := ~A2V

~num1 := -~G * (2.0 * ~M1 + ~M2) * sin(~A1)

~num2 := -~M2 * ~G * sin(~A1 - 2.0 * ~A2)

~num3 := -2.0 * sin(~A1 - ~A2) * ~M2

~num4 := ~A2V * ~A2V * ~L2 + ~A1V * ~A1V * ~L1 * cos(~A1 - ~A2) 

~den := ~L1 * (2.0 * ~M1 + ~M2 - ~M2 * cos(2.0 * ~A1 - 2.0 * ~A2))

~A1A := (~num1 + ~num2 + ~num3  * ~num4) / ~den



~num1 := 2.0 * sin(~A1 - ~A2)

~num2 := ~A1V * ~A1V * ~L1 * (~M1 + ~M2)

~num3 := ~G * (~M1 + ~M2) * cos(~A1)


~num4 := ~A2V * ~A2V * ~L2 * ~M2 * cos(~A1 - ~A2)

~den := ~L2 * (2.0 * ~M1 + ~M2 - ~M2 * cos(2.0 * ~A1 - 2.0 * ~A2))


~A2A := (~num1 * (~num2 + ~num3 + ~num4)) / ~den



$test_int := real_to_int(~A2A)


message($test_int)


  
{~A1V := abs(~A1V)}

end function

on ui_control ($Volume)
set_engine_par($ENGINE_PAR_VOLUME,$test_int,-1,-1,-1)

end on

theodorech

Well written code! Here are a few tips:

1. you need to set a listener in order to trigger somehow the movement
2. you need to call the pendulum function within the LCB
3. you should increment (time steps) the values which take care of the pendulum motion (velocity and angle) so it happens automatically (ie ~A1V := ~A1V + ~A1A * 0.1 and ~A1 := ~A1 + ~A1V * 0.1)
4. AFAIK trigonometric functions should utilize radians and not degrees. It'd be better to use NI_MATH_PI and convert to radians: declare ~A1 := 90.0 * NI_MATH_PI / 180.0

Jamielufc11

Thats great thank you! Ill give all that a shot.

Jamielufc11

https://community.native-instruments.com/discussion/comment/159036#Comment_159036

Hi theodorech

Thanks for your help

I Have given what you suggested a go and Ive made progress but I still not able to get the parameter to modulate. It just returns the value to 0.

I think it may be to do with the time steps you suggested, I'm not fully understanding what to do.

Could you please provide further help.

Thank you again.

See my update code bellow:

on init

make_perfview

set_script_title("Pendulum")

set_ui_height_px(125)
  



declare ui_button $Button

$Button := 0




set_listener($NI_SIGNAL_TIMER_MS,100000)



declare ~L1

~L1 := 100.00

declare ~L2

~L2 := 100.00




declare ~M1

~M1 := 40.00

declare ~M2


~M2 := 40.00
 


declare ~A1


~A1 := 90.0 * ~NI_MATH_PI / 180.0

declare ~A2


~A2 := 90.0 * ~NI_MATH_PI / 180.0
 


declare ~A1V



declare ~A2V



declare ~A1A


declare ~A2A
  



~A1V := ~A1A

~A2V := ~A2A

~A1 := ~A1V

~A2 := ~A2V
  



declare ~G

~G := 9.81




declare ~num1


declare ~num2

declare ~num3

declare ~num4

declare ~den

declare $test_int

end on

function func_pendulum

~A1V := ~A1A

~A2V := ~A2A

~A1 := ~A1V

~A2 := ~A2V

~num1 := -~G * (2.0 * ~M1 + ~M2) * sin(~A1)

~num2 := -~M2 * ~G * sin(~A1 - 2.0 * ~A2)

~num3 := -2.0 * sin(~A1 - ~A2) * ~M2

~num4 := ~A2V * ~A2V * ~L2 + ~A1V * ~A1V * ~L1 * cos(~A1 - ~A2) 


~den := ~L1 * (2.0 * ~M1 + ~M2 - ~M2 * cos(2.0 * ~A1 - 2.0 * ~A2))
 


~A1A := (~num1 + ~num2 + ~num3  * ~num4) / ~den


  
~num1 := 2.0 * sin(~A1 - ~A2)


~num2 := ~A1V * ~A1V * ~L1 * (~M1 + ~M2)


~num3 := ~G * (~M1 + ~M2) * cos(~A1)

~num4 := ~A2V * ~A2V * ~L2 * ~M2 * cos(~A1 - ~A2)

~den := ~L2 * (2.0 * ~M1 + ~M2 - ~M2 * cos(2.0 * ~A1 - 2.0 * ~A2))


~A2A := (~num1 * (~num2 + ~num3 + ~num4)) / ~den



~A1V := ~A1V + ~A1A * 0.1


~A1 := ~A1 + ~A1V * 0.1
 


 $test_int := real_to_int(~A2A)
     




{~A1V := abs(~A1V)}

end function

on listener
  



if ($NI_SIGNAL_TYPE = $NI_SIGNAL_TIMER_MS) 

call func_pendulum

end if

end on

on ui_control ($Button)
if ($Button = 1)

set_engine_par($ENGINE_PAR_VOLUME,$test_int,-1,-1,-1)

end if

end on