generate_force_main.asv

本程序用于对加工夹具进行受力分析 预测被动力

%~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
% Plan the Optimal Normal Clamping Force, and Clamping Position
%~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  global Cn_Lw Cn_cw Ct_Lw Ct_cw
  global t
  global Fg  Side_L Set_Clamping_Force
  global count
  
  
  
%===========================================================================================================
% set the weight of the workpiece
  Fg = -50;                 % weight of the workpiece (Unit: Newton)
  Side_L = 200;             % side Side_L of the workpiece (Unit: mm)
  Set_Clamping_Force = 81.6; % Newton
%=========================================================================================================
% static friction coefficient between the workpiece and locators/clamp(s)
  miu = 0.35; 
%=========================================================================================================  
% Material Characteristics
%---------------------------------------------------------------------------------------------------------
% Modulus of Elasticity 
  EL = 207000;   % for locator   (N/square mm)
  Ec = 207000;   % for clamp     (N/square mm)
  Ew = 70300;    % for workpiece (N/square mm)
% Poisson's Ratio
  vL = 0.292;          % for locator
  vc = 0.292;          % for clamp
  vw = 0.354;          % for workpiece
% Effective Modulus of Elasticity
  ELw = ((1-vw*vw)/Ew+(1-vL*vL)/EL)^(-1); % between locators and workpiece
  Ecw = ((1-vw*vw)/Ew+(1-vc*vc)/Ec)^(-1); % between locators and workpiece
% Effective Resultant Curvature Radius
  RLw = 6.35;       % between locators and workpiece (mm)
  Rcw = 8.05;       % between clamp and workpiece (mm)
% Influence Coefficient
  Cn_Lw = (3/4)*(4/(3*RLw*ELw^2))^(1/3); % for normal direction between locators and workpiece
  Cn_cw = (3/4)*(4/(3*Rcw*Ecw^2))^(1/3); % for normal direction between clamps and workpiece
  
  ELw_ = (1+vL)*(2-vL)/EL+(1+vw)*(2-vw)/Ew;
  Ecw_ = (1+vc)*(2-vc)/Ec+(1+vw)*(2-vw)/Ew;
  
  Ct_Lw = (1/4)*ELw_*(4*ELw/(3*RLw))^(1/3);       % for tangential direction between locators and workpiece
  Ct_cw = (1/4)*Ecw_*(4*Ecw/(3*Rcw))^(1/3);       % for tangential direction between clamps and workpiece
  
%===============================================================================================================

  x0 = [0.0033,0.0038,0.0034,0.0028,0.0026,0.0036,0.0051,-0.00018,-0.00031,-0.00008,0.00014,0.00006,-0.000092,0.00005,-0.0004,-0.00057,-0.00062,-0.0005,-0.00021,0.00009,-0.000058]';
  LB = [0,0,0,0,0,0,0,-0.0025,-0.0025,-0.0025,-0.0025,-0.0025,-0.0025,-0.0025,-0.0025,-0.0025,-0.0025,-0.0025,-0.0025,-0.0025,-0.0025]';
  UB = [0.0075,0.0075,0.0075,0.0075,0.0075,0.0075,0.0075,0.0035,0.0035,0.0035,0.0035,0.0035,0.0035,0.0035,0.0035,0.0035,0.0035,0.0035,0.0035,0.0035,0.0035]';
  
  options = optimset('lsqnonlin');
  options.MaxFunEvals = 20000;
  options.TolFun = 1e-8;
  options.MaxIter = 20000;
  %options.TolX = 1.e-8; 
  
  %fd = fopen('contact_force.dat','w');
  %fd1 = fopen('deformation.dat','w');
  count = 0;     
  for time_step_number=0:36;
      t = 1*time_step_number;
      x = lsqnonlin('Objective_Funct', x0,LB,UB,options);
      
      
      for i=1:6
          Force(i) = (Cn_Lw^(-3/2))*x(i)^(3/2);
          Force(i+7) = (Ct_Lw^(-1))*(Cn_Lw)^(-1/2)*x(i+7)*x(i)^(1/2);
          Force(i+14) = (Ct_Lw^(-1))*(Cn_Lw)^(-1/2)*x(i+14)*x(i)^(1/2);
      end
      Force(7) = Set_Clamping_Force;
      Force(14) = (Ct_cw^(-1))*(Cn_cw)^(-1/2)*x(14)*x(7)^(1/2);
      Force(21) = (Ct_cw^(-1))*(Cn_cw)^(-1/2)*x(21)*x(7)^(1/2);
      
      F1n(time_step_number+1) = Force(1);
      F2n(time_step_number+1) = Force(2);
      F3n(time_step_number+1) = Force(3);
      F4n(time_step_number+1) = Force(4);
      F5n(time_step_number+1) = Force(5);
      F6n(time_step_number+1) = Force(6);
      Fcn(time_step_number+1) = Force(7);
      
      F1t(time_step_number+1) = sqrt(Force(8)^2+Force(15)^2);
      F2t(time_step_number+1) = sqrt(Force(9)^2+Force(16)^2);
      F3t(time_step_number+1) = sqrt(Force(10)^2+Force(17)^2);
      F4t(time_step_number+1) = sqrt(Force(11)^2+Force(18)^2);
      F5t(time_step_number+1) = sqrt(Force(12)^2+Force(19)^2);
      F6t(time_step_number+1) = sqrt(Force(13)^2+Force(20)^2);
      Fct(time_step_number+1) = sqrt(Force(14)^2+Force(21)^2);
      
      Dlt_F1(time_step_number+1) =  0.4*F1n(time_step_number+1)-F1t(time_step_number+1)
      Dlt_F2(time_step_number+1) =  0.4*F2n(time_step_number+1)-F2t(time_step_number+1)
      Dlt_F3(time_step_number+1) =  0.4*F3n(time_step_number+1)-F3t(time_step_number+1)
      Dlt_F4(time_step_number+1) =  0.4*F4n(time_step_number+1)-F4t(time_step_number+1)
      Dlt_F5(time_step_number+1) =  0.4*F5n(time_step_number+1)-F5t(time_step_number+1)
      Dlt_F6(time_step_number+1) =  0.4*F6n(time_step_number+1)-F6t(time_step_number+1)
      Dlt_Fc(time_step_number+1) =  0.4*Fcn(time_step_number+1)-Fct(time_step_number+1)
      
      
      
      
      %fprintf(fd, '\n%d %f %f %f %f %f %f %f %f %f %f %f %f %f %f %f %f %f %f %f %f %f \n', 5*t, F1n, F1t, Dlt_F1,F2n, F2t, Dlt_F2,F3n, F3t, Dlt_F3,F4n, F4t, Dlt_F4,F5n, F5t, Dlt_F5,F6n, F6t, Dlt_F6,Fcn, Fct, Dlt_Fc);
      %fprintf(fd1, '\n%d %f %f %f %f %f %f \n', 5*t, Dlt_X, Dlt_Y, Dlt_Z, Dlt_CT_X, Dlt_CT_Y, Dlt_CT_Z);
  end
  
  
  
  %fclose(fd);
  %fclose(fd1);
  
  close all;
  
  figure(1);
  hold on;
  plot(0:5:180, F1n,'-*b' );
  plot(0:5:180, F1t,'-ok');
  plot(0:5:180, Dlt_F1, '-xr');
  grid on;
  xlabel('Position of Cutter (mm)');
  ylabel('Force (N)');
  title('Forces at the 1st Contact');
  legend('Normal Force','Tangential Force','Sliding Index');
  
  figure(2);
  hold on;
  plot(0:5:180, F2n,'-*b' );
  plot(0:5:180, F2t,'-ok');
  plot(0:5:180, Dlt_F2, '-xr');
  grid on;
  xlabel('Position of Cutter (mm)');
  ylabel('Force (N)');
  title('Forces at the 2nd Contact');
  legend('Normal Force','Tangential Force','Sliding Index');
    
  figure(3);
  hold on;
  plot(0:5:180, F3n,'-*b' );
  plot(0:5:180, F3t,'-ok');
  plot(0:5:180, Dlt_F3, '-xr');
  grid on;
  xlabel('Position of Cutter (mm)');
  ylabel('Force (N)');
  title('Forces at the 3rd Contact');
  legend('Normal Force','Tangential Force','Sliding Index');
    
  figure(4);
  hold on;
  plot(0:5:180, F4n,'-*b' );
  plot(0:5:180, F4t,'-ok');
  plot(0:5:180, Dlt_F4, '-xr');
  grid on;
  xlabel('Position of Cutter (mm)');
  ylabel('Force (N)');
  title('Forces at the 4th Contact');
  legend('Normal Force','Tangential Force','Sliding Index');
    
  figure(5);
  hold on;
  plot(0:5:180, F5n,'-*b' );
  plot(0:5:180, F5t,'-ok');
  plot(0:5:180, Dlt_F5, '-xr');
  grid on;
  xlabel('Position of Cutter (mm)');
  ylabel('Force (N)');
  title('Forces at the 5th Contact');
  legend('Normal Force','Tangential Force','Sliding Index');
  
  figure(6);
  hold on;
  plot(0:5:180, F6n,'-*b' );
  plot(0:5:180, F6t,'-ok');
  plot(0:5:180, Dlt_F6, '-xr');
  grid on;
  xlabel('Position of Cutter (mm)');
  ylabel('Force (N)');
  title('Forces at the 6th Contact');
  legend('Normal Force','Tangential Force','Sliding Index');
  
  figure(7);
  hold on;
  plot(0:5:180, Fcn,'-*b' );
  plot(0:5:180, Fct,'-ok');
  plot(0:5:180, Dlt_Fc, '-xr');
  grid on;
  xlabel('Position of Cutter (mm)');
  ylabel('Force (N)');
  title('Forces at the 7th Contact');
  legend('Normal Force','Tangential Force','Sliding Index');