Magnetic.Solenoid.Utilities

Name	Description
Stopper	1D translational spring damper combination with gap and nonlinear force function
ArmatureMechanics

Magnetic.Solenoid.Utilities.ArmatureMechanics

Information

The mechanical subsystem of a translational actuator with limited stroke is described by a sliding mass that can move between stoppers at the maximum respectively minimum position.

Modelica definition

model ArmatureMechanics 
  Modelica.Mechanics.Translational.Interfaces.Flange_b flange_b;
  Modelica.Mechanics.Translational.Fixed limit_xMin(s0=0);
  Modelica.Mechanics.Translational.SlidingMass ArmatureMass(m=1);
  Magnetic.Solenoid.Utilities.Stopper Stopper_xMax(
    c=1e6,
    d=2e2,
    s_n=10e-6);
  Magnetic.Solenoid.Utilities.Stopper Stopper_xMin(
    c=1e6,
    d=2e2,
    s_n=10e-6);
  Modelica.Mechanics.Translational.Fixed limit_xMax(s0=10e-3);
  Modelica.Mechanics.Translational.Interfaces.Flange_a flange_a;
equation 
  connect(ArmatureMass.flange_b, flange_b);
  connect(Stopper_xMin.flange_a, limit_xMin.flange_b);
  connect(Stopper_xMin.flange_a, limit_xMin.flange_b);
  connect(ArmatureMass.flange_a, Stopper_xMin.flange_b);
  connect(limit_xMax.flange_b, Stopper_xMax.flange_b);
  connect(Stopper_xMax.flange_a, ArmatureMass.flange_b);
  connect(ArmatureMass.flange_a, flange_a);
end ArmatureMechanics;

Magnetic.Solenoid.Utilities.Stopper

Information

Th. Hegewald, TU Dresden 2001

Mathematical model describing the impact based on:
Kamusella, A.: USAN-Handbuch. Institut fuer Feinwerktechnik: Technische Universitaet Dresden 1999

Modelica implementation of the above model based on Modelica.Mechanics.Translational.ElastoGap

Parameters

Name	Default	Description
s_rel0	0	unstretched spring length [m]
c	1e6	spring constant [N/m]
d	2e2	damping constant [N/ (m/s)]
s_n	1e-6	normalized entering depth [m]
n	1	exponent for force function (n>=1)

Modelica definition

class Stopper 
  "1D translational spring damper combination with gap and nonlinear force function" 
  
  extends Modelica.Mechanics.Translational.Interfaces.Compliant;
  parameter SI.Position s_rel0=0 "unstretched spring length";
  parameter Real c(
    final unit="N/m",
    final min=0) = 1e6 "spring constant";
  parameter Real d(
    final unit="N/ (m/s)",
    final min=0) = 2e2 "damping constant";
  SI.Velocity v_rel "relative velocity between flange L and R";
  Boolean Contact "false, if s_rel > 0 ";
  parameter SI.Position s_n=1e-6 "normalized entering depth";
  parameter Real n=1 "exponent for force function (n>=1)";
  SI.Velocity delta_v "equals relative velocity for movement ";
  SI.Position delta_s "equals (s_rel - s_rel0)";
equation 
  
  v_rel = der(s_rel);
  Contact = s_rel < s_rel0;
  delta_s = abs(s_rel - s_rel0);
  delta_v = if (v_rel < 0) then v_rel else 0;
  f = if Contact then ((c*(s_rel - s_rel0) + d*delta_v)*(delta_s/s_n)^n) else 
          0;
end Stopper;