function dataexperiment(filling)
    ## internal tank ("sloshing related" parameters):
    # [pslosh pbeam prigid] = dataexperiment(filling)
	pslosh = Dict()
    pslosh["g"] = 9.8; # m/s^2
    pslosh["rho"] = 999; # water density: kg/m^3      #    +- 1
    L = 0.470;    # tank internal length (m)       #   +- 0.001
    R = 0.105/2; # tank internal radius (m)        #   +- 0.0002
    e = filling;
    #"equivalent" rectangular tank (same surface area and volume):
    theta = 2*acos(1-2*e);
    ls = 2*R*sqrt(1-(2*e-1)^2);
    Vcyl = R^2/2*(theta-sin(theta))*L;

    pslosh["a"] = L;           # rectangular tank length
    pslosh["b"] = ls;          # rectangular tank width
    pslosh["h"] = Vcyl/ls/L;   # rectangular tank liquid height
    
    pslosh["R"] = R;
    pslosh["H"] = e*2*R;
    ## structural parameters
    #plate parameters   - data in Ref. Robu2012,  'Simultaneous Hinf Vibration
    # Control of Fluid/Plate via Reduced-Order Controller')
    # --- IEEE Transactions on Control Sys Tech:
    E = 75e9; #Young modulus
    mu = 0.33;  #Poisson ratio
    rho = 2970; #density
    L = 1.36; #length
    h = 0.005;  #thickness       +- 0.00005
    l = 0.16;   #width           +- 0.001

    mrb = 0; # rigid body (tank) mass (here it is zero since we are adding
    # all rigid bodies when coupling with sloshing ("D" matrix))
    Irb = 0; # rigid body (tank) inertia (along axis x and y)
    xrb = 1.28; # position of rigid body (along axis x)        +- 0.001
	
	pbeam = Dict()
    pbeam["E"] = E; pbeam["mu"] = mu; pbeam["L"] = L; pbeam["rho"] = rho; pbeam["h"] = h;
    pbeam["l"] = l; pbeam["mrb"] = mrb; pbeam["Irb"] = Irb; pbeam["xrb"] = xrb;

    # piezoelectric data (data in ref. Robu 2012)
    rhop = 7800; # density
    Ep = 67e9; # young modulus
    tp = 5e-4; # thickness
    d31 = -2.1e-10; # piezoelectric constant
	
    pbeam["Ep"] = Ep; pbeam["tp"] = tp; pbeam["d31"] = d31; pbeam["rhop"] = rhop;

    ## rigid mass and inertias
    #(tank, fixation rings and fluid inertia in "y" direction)    
    #tank:
    
    # tank data - data in Robu2012/IEEE
    rhoplast = 1180; # plastic density (kg/m^3)
    Der = 0.11;      # tank external diameter (m)
    Dir = 0.105;     # tank internal diameter (m)
    Lr = 0.50;       # tank length (m)              +- 0.001

    # fixation rings data - data measured/approximated
    # obs.: external diameter and thickness doesn't represent the exact
    # values. actually, the fixation rings have several holes/screws.
    # Def, Di and hf are approximate values. They were adjusted so that
    # the TOTAL fixation ring masses are the measured ones
    #   (588.6g)
    rhofix = 2970;       # fixation rings density (= plate,kg/m^3)
    Def = 0.1445 + 0.15*0; # fixation rings external diameter (m)
    Dif = 0.11;            # fixation rings internal diameter (m)
    hf = 0.02876+0.0325*0; # fixation rings thickness (m)
    distf = (h+hf)/2;      # fixation rings position (relative to plate mean axis) (m)

    Dh = Der;        # PLATE hole diameter (m)
    massrlat = rhoplast* pi * (Der^2-Dir^2)/4 * Lr; # tank lateral mass 
    massrtip = 0.313/2;     # each tip mass (measured)
                            # OBS.: the tip mass was obtained by measuring
                            # the tank mass and comparing with the predicted
                            # lateral tank mass. In order to confirm if the
                            # lateral tank mass was correct, I also
                            # compared the results with a 30cm tank (in
                            # addition to the 50cm one).
                            # The tip consists of: plastic disc + glue +
                            # plug: not so simple geometry, but the effects
                            # on the system mass/inertia can be
                            # approximated as a point mass.
    massfix = rhofix*pi*(Def^2-Dif^2)/4 * hf;         # each fixation rings total
    masshole = rho*pi*Dh^2/4 * h;                     # plate hole mass - it will reduce the rigid unit mass!
    mass = (massrlat + massrtip*2+2*massfix-masshole);# total rigid added mass (kg)
    
    # calculate rigid body inertia (x and y direction, since tank and
    # fixation rings are symmetric):
    Inertialat = (massrlat/12*(3*(Der^2+Dir^2)/4+Lr^2)); # tank lateral inertia
    Inertiatip = massrtip*(Lr/2-0.01)^2; # tank tip inertia
    Inertiafix = massfix*(3*(Dif^2+Def^2)/4+hf^2)/12+massfix*distf^2; # fixation rings inertia
    Inertiahole = masshole*(Dh^2)/16;   # inertia of hole in the plate
    Inertia = (Inertialat + 2*Inertiatip + 2*Inertiafix - Inertiahole); #(kg.m^2)
 
    # "frozen" fluid inertia (y direction)
    massfluid = pslosh["a"]*pslosh["b"]*pslosh["h"]*pslosh["rho"];
    IFLUID = massfluid*pslosh["a"]^2/12;    #(kg.m^2)
    
	prigid = Dict()
    prigid["xrb"] = xrb; #position of rigid units (m)
    prigid["mass"] = mass; #tank + fixation rings mass (kg)
    prigid["Inertia"] = Inertia; #tank + fixation rings inertia ("y" and "z" directions) (kg.m^2)
    prigid["Ifluid"] = IFLUID; # "frozen" fluid inertia in "y" direction (kg.m^2)
    prigid["massfluid"] = massfluid; # "frozen" fluid mass
    
    ## auxiliary equations and parameters: most equations are implemented on
    # other codes
    # they are repeated here only for verification purposes

    # beam structural parameters
    J = 0.33*l*h^3;              # torsion constant
    IY = rho/12*(l^2 + h^2)*l*h; # section moment of inertia (X direction)  # VERIFICAR!!!
    Iz = l*h^3/12;               # section area inertia (X direction)
    Ix = l^3*h/12;               # section area inertia (X direction)
    G = E/2/(1+mu);              # shear modulus
   
   return (pslosh, pbeam, prigid)
end

## measures:
# large tank: 50 cm  (47 cm liquid)
# tank filled up to 34.3 cm (+-0.2):
#    mass = 3820.3 g +- 0.1 g
# tank filled 100 #:
#    mass = 4938.0 g +- 0.4 g
# tank filled 0#:
#    mass = 821.8 g +- 0.1 g
#
# small tank: 30 cm (27 cm liquid)
#  empty tank:
#    606.7 g +- 0.1 g
#
# small tank: 30 cm (27 cm liquid): broken one
#    578.1 g +- 0.1 g
#

## new measures:
# TANK WEIGHT:
#   * empty: 818.2 gramas (erro do aparelho: 0.1, mas gotas extras
#   podem adicionar uns 0.2 g)
#   * 0 +-0.1cm:      839.8  +-0.1g
#   * 20.2 +- 0.2cm: 2551.2  +-0.2g
#   * 35.0 +- 0.1cm: 3879.2  +-0.2g
#   * 47.0 +- 0.1cm: 4933.4  +-0.2g
#   * full: 4939.9 +- 0.1 g (mas nao estava 100# cheio, impossivel
#   fazer isso)
#
# TANK medidas dos bouchons individuais: 15.9, 15.8, 16.7, 16.2
# (gramas)
#
# TANK dimensoes:
# L = 30.0 +-0.1 cm
# Li = 27.0 +- 0.1cm
# espessura do disco interno de plastico: 0.70 +-0.05 cm
# distancia entre a parte interna do disco e o fim do bouchon: 4.5cm
# distancia entre a parte interna do disco e a extremidade: 1.5cm
#
#
# ANEIS de fixacao:
#  1) lado direito (visto de frente)
#       561.4 g (sem parafusos)
#       568.2 g (parafuso central)
#       580.6 g (parafuso central+interm)
#       596.2 g (parafuso central+interm+sup)
#   2) lado esquerdo
#       565.3 g (sem parafusos)
#       580.9 g (parafuso superior)
#
#
# peso dos parafusos do anel:
#   central: 3.3g
#   interm: 6.2g
#   sup: 15.7g
#
# dimensoes do anel:
#  diametro exterior 1: 16.0cm, 16.0cm, 16.0cm +- 0.1
#  diametro exterior 2 (anel 1): 145.46mm, 145.52mm,145.45mm,145.40mm
#  diametro exterior 2 (anel 2): 144.62mm, 144.56mm,144.51mm
#  diametro interior (anel 1): 110.53mm, 110.8mm,110.81mm,110.72mm
#  diametro interior (anel 2): 110.73mm, 110.90mm,110.62mm
#  altura placa fina: 5.16 5.22 5.02 4.97 4.48mm
#  altura total anel: 30.15 30.01 30.13 29.79mm
#
#
# DIMENSOES DA PLACA
#    comprimento: 136.3 +-0.2 cm
#    largura: 16.0 +- 0.1 cm
#    espessura: 4.95mm, 4.98mm, 4.92mm, 4.92mm, 4.84mm, 5.02mm, 4.88mm,
#    4.86mm
#
#
# POSICAO DO FURO NA PLACA:
#  relativo a ponta da placa:
#    entre 2.4cm e 13.65cm
#  diametro interno do furo:
#          112.05 +-0.3mm


