Public Sub end_button_Click()
Unload userform1
End Sub

Public Sub ok_Click()
Dim mr As Variant, m As Variant, m0 As Variant, lam As Variant, a2 As Variant
'to get the input values from the userform
	strke = Val(stroke.Text)
	d = Val(dia.Text)
	conrod_length = Val(l.Text)
	cg_conrod = Val(l_dash.Text)
	pist_mass = Val(pmass.Text)
	conrod_mass = Val(conmass.Text)
	crankpin_mass = Val(crank_mass.Text)
	mr = (pist_mass * (conrod_length - cg_conrod) / conrod_length) + crankpin_mass
	m = (cg_conrod * conrod_mass / conrod_length) + pist_mass
	r = strke / 2
	lam = r / conrod_length
	a1 = 1
	a2 = lam + ((1 / 4) * (lam) ^ 3) + ((15 / 128) * (lam) ^ 5)
	cr_m1 = Val(crank_mass1)
	cr_r1 = Val(crank_rad1)
	cw_m1 = Val(counter_mass1)
	cw_r1 = Val(counter_rad1)
	cr_m2 = Val(crank_mass2)
	cr_r2 = Val(crank_rad2)
	cw_m2 = Val(counter_mass2)
	cw_r2 = Val(counter_rad2)
	eqm1 = (cr_m1 * cr_r1) - (cw_m1 * cw_r1)
	eqm2 = (cr_m2 * cr_r2) - (cw_m2 * cw_r2)
	m0 = (eqm1 + eqm2)
'the loop
	Dim k As Variant
	For f = 2 To Selection.CurrentRegion.Rows.Count - 1
		Set i = Worksheets("input").Cells(f, 1)
		Set k = Worksheets("input").Cells(f, 2)
		y = rad(i)
		p = k * 0.1
			Cells(f, 16).Select
			Selection.Value = p
		a = Area(d)
		fz = p * a
			Cells(f, 17).Select
			Selection.Value = fz
		fzm = Forcezm(r, mr, m0, y, m, a1, a2)
			Cells(f, 18).Select
			Selection.Value = fzm
		fym = Forceym(r, mr, mo, y, m)
			Cells(f, 19).Select
			Selection.Value = fym
		vp = vprmf(r, m, y)
			Cells(f, 20).Select
			Selection.Value = vp
		vs = vsrmf(r, m, a2, y)
			Cells(f, 21).Select
			Selection.Value = vs
		trf = vp + vs
			Cells(f, 22).Select
			Selection.Value = trf
		rf = trf - fz
			Cells(f, 23).Select
			Selection.Value = rf
		fn = pistonst(rf, lam, y)
			Cells(f, 24).Select
			Selection.Value = fn
	Next f
End Sub

		Function Area(d As Variant) As Variant
		pi = 22 / 7
		Area = (pi * (d ^ 2)) / 4
		End Function

	Function Forcezm(r As Variant, mr As Variant, m0 As Variant, y As Variant, m As Variant, a1 As Variant, a2 As Variant) As Variant
	pi = 22 / 7
	rpm = Val(speed.Text)
	Forcezm = r * (((2 * pi * rpm) / 60) ^ 2) * (((mr * m0) * 0.001 * Cos(y)) + (m * 0.001 * a1 * Cos(y)) + (m * 0.001 * a2 * (Cos(2 * y))))
	End Function

		Function Forceym(r As Variant, mr As Variant, m0 As Variant, y As Variant, m As Variant) As Variant
		pi = 22 / 7
		rpm = Val(speed.Text)
		Forceym = r * (((2 * pi * rpm) / 60) ^ 2) * ((mr + m0) * 0.001 * Sin(y))
		End Function

	Function rad(i As Variant) As Variant
	pi = 22 / 7
	rad = (i * pi) / 180
	End Function

		Function Pre(p As Variant) As Variant
		Pre = p * 0.1
		End Function

	Function vprmf(r As Variant, m As Variant, y As Variant) As Variant
	pi = 22 / 7
	rpm = Val(speed.Text)
	vprmf = r * (((2 * pi * rpm) / 60) ^ 2) * m * 0.001 * Cos(y)
	End Function
		
		Function vsrmf(r As Variant, m As Variant, a2 As Variant, y As Variant) As Variant
		pi = 22 / 7
		rpm = Val(speed.Text)
		vsrmf = r * (((2 * pi * rpm) / 60) ^ 2) * m * 0.001 * a2 * (Cos(2 * y))
		End Function

	Function pistonst(rf As Variant, lam As Variant, y As Variant) As Variant
	pistonst = (rf * lam * Sin(y)) / ((1 - (lam * lam) * ((Sin(y)) ^ 2)) ^ 0.5)
	End Function