Add multiple scripts (compute/plot max pos, effect of param)

getMaxPositions.m

@@ -1,4 +1,4 @@
-function [X, Y, Z] = getMaxPositions(lmax, J)
+function [X, Y, Z] = getMaxPositions(Leg, J)
     theta = linspace(0, 2*pi, 100);
     phi = linspace(-pi/2 , pi/2, 100);
     dmax = zeros(length(theta), length(phi));
@@ -6,7 +6,7 @@ function [X, Y, Z] = getMaxPositions(lmax, J)
     for i = 1:length(theta)
         for j = 1:length(phi)
             L = J*[cos(phi(j))*cos(theta(i)) cos(phi(j))*sin(theta(i)) sin(phi(j)) 0 0 0]';
-            dmax(i, j) = lmax/max(abs(L));
+            dmax(i, j) = Leg.stroke/max(abs(L));
         end
     end
 

getMaxPureDisplacement.m

@@ -0,0 +1,9 @@
+function [max_disp] = getMaxPureDisplacement(Leg, J)
+    max_disp = zeros(6, 1);
+    max_disp(1) = Leg.stroke/max(abs(J*[1 0 0 0 0 0]'));
+    max_disp(2) = Leg.stroke/max(abs(J*[0 1 0 0 0 0]'));
+    max_disp(3) = Leg.stroke/max(abs(J*[0 0 1 0 0 0]'));
+    max_disp(4) = Leg.stroke/max(abs(J*[0 0 0 1 0 0]'));
+    max_disp(5) = Leg.stroke/max(abs(J*[0 0 0 0 1 0]'));
+    max_disp(6) = Leg.stroke/max(abs(J*[0 0 0 0 0 1]'));
+end

getStiffnessMatrix.m

@@ -0,0 +1,3 @@
+function [K] = getStiffnessMatrix(leg, J)
+    K = leg.k.ax*(J'*J);
+end

plot_max_positions.m

@@ -1,10 +1,12 @@
-lmax = 80e-6;
+%%
+run stewart_parameters.m
+run stewart_init.m
 
-[X, Y, Z] = getMaxPositions(lmax, J);
+%%
+[X, Y, Z] = getMaxPositions(Leg, J);
 
 figure;
 hold on;
 mesh(X, Y, Z);
 colorbar;
 hold off;
-

stewart_init.m

@@ -1,11 +1,3 @@
-%%
-clear;
-close all;
-clc;
-
-%%
-run stewart_parameters.m
-
 %% Define some constant values
 deg2rad = pi/180;
 x_axis = [1 0 0];
@@ -19,7 +11,7 @@ pos_top = zeros(6, 3);
 alpha_b = BP.leg.ang*deg2rad; % angle de décalage par rapport à 120 deg (pour positionner les supports bases)
 alpha_t = TP.leg.ang*deg2rad; % +- offset angle from 120 degree spacing on top
 
-height = (stewart.h-BP.thickness-TP.thickness-Leg.sphere.bottom-Leg.sphere.top-SP.thickness.bottom-SP.thickness.top)*0.001 ; % 2 meter height in home configuration
+height = (stewart.h-BP.thickness-TP.thickness-Leg.sphere.bottom-Leg.sphere.top-SP.thickness.bottom-SP.thickness.top)*0.001; % 2 meter height in home configuration
 
 radius_b = BP.leg.rad*0.001; % rayon emplacement support base
 radius_t = TP.leg.rad*0.001; % top radius in meters

stewart_parameters.m

@@ -5,55 +5,56 @@ stewart.jacobian = 174.5; %mm
 
 %% Bottom Plate
 BP = struct();
-BP.rad.int = 105 ; %mm
+BP.rad.int = 105; %mm
-BP.rad.ext = 152.5 ; %mm
+BP.rad.ext = 152.5; %mm
 BP.thickness = 8; % mm
-BP.leg.rad = 142 ; %mm
+BP.leg.rad = 142; %mm
-BP.leg.ang = 5 ; %deg
+BP.leg.ang = 5; %deg
-BP.density = 8000 ; %kg/m^3
+BP.density = 8000; %kg/m^3
-BP.color = [0.5 0.5 0.5] ; %rgb
+BP.color = [0.5 0.5 0.5]; %rgb
 
 %% TOP Plate
 TP = struct();
-TP.rad.int = 0 ;%mm
+TP.rad.int = 0;%mm
-TP.rad.ext = 120 ; %mm
+TP.rad.ext = 120; %mm
 TP.thickness = 8; % mm
-TP.leg.rad = 100 ; %mm
+TP.leg.rad = 100; %mm
-TP.leg.ang = 5 ; %deg
+TP.leg.ang = 5; %deg
-TP.density = 8000 ; %kg/m^3
+TP.density = 8000; %kg/m^3
-TP.color = [0.5 0.5 0.5] ; %rgb
+TP.color = [0.5 0.5 0.5]; %rgb
 
 %% Leg
 Leg = struct();
-Leg.rad.bottom = 8 ; %mm
+Leg.stroke = 80e-6; % m
-Leg.rad.top = 5 ; %mm
+Leg.rad.bottom = 8; %mm
-Leg.sphere.bottom = 10 ; % mm
+Leg.rad.top = 5; %mm
-Leg.sphere.top = 8 ; % mm
+Leg.sphere.bottom = 10; % mm
-Leg.density = 8000 ; %kg/m^3
+Leg.sphere.top = 8; % mm
+Leg.density = 8000; %kg/m^3
 Leg.lenght = stewart.h; % mm (approximate)
 Leg.m = Leg.density*2*pi*((Leg.rad.bottom*1e-3)^2)*(Leg.lenght*1e-3); %kg
-Leg.color.bottom = [0.5 0.5 0.5] ; %rgb
+Leg.color.bottom = [0.5 0.5 0.5]; %rgb
-Leg.color.top = [0.5 0.5 0.5] ; %rgb
+Leg.color.top = [0.5 0.5 0.5]; %rgb
 Leg.k.ax = 5e7; % N/m
-Leg.ksi.ax = 10 ;
+Leg.ksi.ax = 10;
 Leg = updateDamping(Leg);
 
 
 %% Sphere
 SP = struct();
-SP.thickness.bottom = 1 ; %mm
+SP.thickness.bottom = 1; %mm
-SP.thickness.top = 1 ; %mm
+SP.thickness.top = 1; %mm
-SP.rad.bottom = Leg.sphere.bottom ; %mm
+SP.rad.bottom = Leg.sphere.bottom; %mm
-SP.rad.top = Leg.sphere.top ; %mm
+SP.rad.top = Leg.sphere.top; %mm
-SP.height.bottom = 5 ; %mm
+SP.height.bottom = 5; %mm
-SP.height.top = 5 ; %mm
+SP.height.top = 5; %mm
-SP.density.bottom = 8000 ; %kg/m^3
+SP.density.bottom = 8000; %kg/m^3
-SP.density.top = 8000 ; %kg/m^3
+SP.density.top = 8000; %kg/m^3
 SP.m = SP.density.bottom*2*pi*((SP.rad.bottom*1e-3)^2)*(SP.height.bottom*1e-3); %kg
-SP.color.bottom = [0.5 0.5 0.5] ; %rgb
+SP.color.bottom = [0.5 0.5 0.5]; %rgb
-SP.color.top = [0.5 0.5 0.5] ; %rgb
+SP.color.top = [0.5 0.5 0.5]; %rgb
-SP.k.ax = 0 ; % N*m/deg
+SP.k.ax = 0; % N*m/deg
-SP.ksi.ax = 1 ;
+SP.ksi.ax = 1;
 SP = updateDamping(SP);
 
 %%

study_architecture.m

@@ -0,0 +1,52 @@
+%%
+run stewart_parameters.m
+format shortE
+
+%% Study the effect of the radius of the top platform position of the legs
+leg_radius = 50:1:120;
+max_disp   = zeros(length(leg_radius), 6);
+stiffness  = zeros(length(leg_radius), 6, 6);
+
+for i_leg = 1:length(leg_radius)
+    TP.leg.rad = leg_radius(i_leg);
+    run stewart_init.m;
+    max_disp(i_leg, :) = getMaxPureDisplacement(Leg, J)';
+    stiffness(i_leg, :, :) = getStiffnessMatrix(Leg, J);
+end
+
+%% Plot everything
+figure;
+hold on;
+plot(leg_radius, max_disp(:, 1))
+plot(leg_radius, max_disp(:, 2))
+plot(leg_radius, max_disp(:, 3))
+hold off;
+legend({'tx', 'ty', 'tz'})
+xlabel('Leg Radius at the platform'); ylabel('Maximum translation (m)');
+
+figure;
+hold on;
+plot(leg_radius, max_disp(:, 4))
+plot(leg_radius, max_disp(:, 5))
+plot(leg_radius, max_disp(:, 6))
+hold off;
+legend({'rx', 'ry', 'rz'})
+xlabel('Leg Radius at the platform'); ylabel('Maximum rotations (rad)');
+
+figure;
+hold on;
+plot(leg_radius, stiffness(:, 1, 1))
+plot(leg_radius, stiffness(:, 2, 2))
+plot(leg_radius, stiffness(:, 3, 3))
+hold off;
+legend({'kx', 'ky', 'kz'})
+xlabel('Leg Radius at the platform'); ylabel('Stiffness in translation (N/m)');
+
+figure;
+hold on;
+plot(leg_radius, stiffness(:, 4, 4))
+plot(leg_radius, stiffness(:, 5, 5))
+plot(leg_radius, stiffness(:, 6, 6))
+hold off;
+legend({'mx', 'my', 'mz'})
+xlabel('Leg Radius at the platform'); ylabel('Stiffness in rotations (N/(m/rad))');