#It is presumed that QuickField is already started, the problem coil.pbm is opened.

#===============================================
#calculates force in QuickField
#===============================================
function getQfForceX ($x_position)
	{
#0. open model
#1. check plunger position, move plunger
#2. calculate force


# 0. open model
	$QF =  new-object -comobject QuickField.Application	#hook QuickField
	$pbm = $QF.Problems.Item(1)	#get the first opened Problem
	$pbm.LoadModel() 				#load Model
	$mdl = $pbm.Model				#hook the Model
	
#1. check plunger x-position, the cooridate of vertex "R" on plunger
	$theVertex = $mdl.Shapes.Vertices.LabeledAs("R","","").Item(1)
	$theXposition = $theVertex.Point.X;	#calculate x-coordinate of vertex "position"
	$theVector = $QF.PointXY($x_position - $theXposition, 0)	#calculate displacement vector
#plunger consists of 2 blocks: "insulation" (external), "plunger_core" (internal)
#if we move the external block then the internal block will be moved too	
	$theBlock = $mdl.Shapes.Blocks.LabeledAs("","","insulation").Item(1)#select "plunger" block	
	$theBlock.Move(0, $theVector)		#move plunger. 0=qfShift, displacement



#2. Solve problem
	$mdl.Shapes.BuildMesh($True,$False)	#build mesh
	$mdl.Save();				#save model
	if (-Not($pbm.Solved))			#check if problem is solved
		{
		$pbm.SolveProblem()		#solve problem
		};
	$pbm.AnalyzeResults()			#open results
	$res = $pbm.Result			#link to Result object
    

	$theFieldWindow = $res.GetFieldWindow(1)#hook Field window
	$theContour = $theFieldWindow.Contour	#build integration contour
#plunger consists of 2 blocks: "insulation" (external), "plunger_core" (internal)
	$theContour.AddBlock1("insulation")	#add to contour block "insulation"
	$theContour.AddBlock1("plunger_core")	#add to contour block "plunger_core"

#calculate magnetic force integral
    	$theForce = $res.GetIntegral(15, $theContour).Value #15=qfInt_MaxwellForce
    	return $theForce.X			#get x-component of force
	}

	

#===============================================
# main programm starts here
#===============================================

#relay physical parameters
$x_out = 0.01       		# pull out position. m
$x_in = 0.006       		# pull in position, m
$m_mass = 0.0045     		# plunger weight, kg
$k = 4.0            		# spring constant, N/m
$x_spring_free = 0.015  	# spring free would be position, m


#initial conditions
$t_time = 0.0    	# time, s
$x_position = $x_out  	# plunger position, m
$v_speed = 0.0		# plunger speed, m/s


$dt_time_step = 0.005	#integration time step, s
$max_time = 0.2		# maximal integration time


echo "Time [s]	Position [m]	Speed[m/s]"

while (($t_time -lt $max_time) -and ($x_position -gt $x_in))
	{
	$theForce = getQfForceX($x_position)				# electromagnetic force
    #in PowerShell function return collects _all_ calculated values
    #if they are not assigned to variables
    #execution $theContour.AddBlock1 in function adds "TRUE" to the output,
    #so the output is an array and we have to use [-1] - to get the last value
    $theForceX = $theForce[-1]
    $theForceX = $theForceX + ($x_spring_free - $x_position) * $k	# add spring force
    $v_speed += $theForceX / $m_mass * $dt_time_step 	# calculate acceleration and speed
    $x_position += $v_speed * $dt_time_step		# calculate plunger position
	$t_time += $dt_time_step			#time increment
	echo "$t_time	$x_position	$v_speed"	#output results
	}