tdehaeze/stewart-simscape
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

Add Compliance and Transmissibility computation

Browse Source 
Change solid to rigid
This commit is contained in:
Thomas Dehaeze
2020-02-27 11:45:54 +01:00
parent a83598d7dd
commit 1321d12e4d
7 changed files with 653 additions and 18 deletions
Download Patch File Download Diff File Expand all files Collapse all files

83
src/computeCompliance.m Normal file
View File

@@ -0,0 +1,83 @@
function [C, C_norm, freqs] = computeCompliance(args)
% computeCompliance -
%
% Syntax: [C, C_norm, freqs] = computeCompliance(args)
%
% Inputs:
% - args - Structure with the following fields:
% - plots [true/false] - Should plot the transmissilibty matrix and its Frobenius norm
% - freqs [] - Frequency vector to estimate the Frobenius norm
%
% Outputs:
% - C [6x6 ss] - Compliance matrix
% - C_norm [length(freqs)x1] - Frobenius norm of the Compliance matrix
% - freqs [length(freqs)x1] - Frequency vector in [Hz]
arguments
args.plots logical {mustBeNumericOrLogical} = false
args.freqs double {mustBeNumeric, mustBeNonnegative} = logspace(1,4,1000)
end
freqs = args.freqs;
%% Options for Linearized
options = linearizeOptions;
options.SampleTime = 0;
%% Name of the Simulink File
mdl = 'stewart_platform_model';
%% Input/Output definition
clear io; io_i = 1;
io(io_i) = linio([mdl, '/Disturbances/F_ext'], 1, 'openinput'); io_i = io_i + 1; % External forces [N, N*m]
io(io_i) = linio([mdl, '/Absolute Motion Sensor'], 1, 'openoutput'); io_i = io_i + 1; % Absolute Motion [m, rad]
%% Run the linearization
C = linearize(mdl, io, options);
C.InputName = {'Fdx', 'Fdy', 'Fdz', 'Mdx', 'Mdy', 'Mdz'};
C.OutputName = {'Edx', 'Edy', 'Edz', 'Erx', 'Ery', 'Erz'};
p_handle = zeros(6*6,1);
if args.plots
fig = figure;
for ix = 1:6
for iy = 1:6
p_handle((ix-1)*6 + iy) = subplot(6, 6, (ix-1)*6 + iy);
hold on;
plot(freqs, abs(squeeze(freqresp(C(ix, iy), freqs, 'Hz'))), 'k-');
set(gca, 'XScale', 'log'); set(gca, 'YScale', 'log');
if ix < 6
xticklabels({});
end
if iy > 1
yticklabels({});
end
end
end
linkaxes(p_handle, 'xy')
xlim([freqs(1), freqs(end)]);
han = axes(fig, 'visible', 'off');
han.XLabel.Visible = 'on';
han.YLabel.Visible = 'on';
xlabel(han, 'Frequency [Hz]');
ylabel(han, 'Compliance [m/N, rad/(N*m)]');
end
freqs = args.freqs;
C_norm = zeros(length(freqs), 1);
for i = 1:length(freqs)
C_norm(i) = sqrt(trace(freqresp(C, freqs(i), 'Hz')*freqresp(C, freqs(i), 'Hz')'));
end
if args.plots
figure;
plot(freqs, C_norm)
set(gca, 'XScale', 'log'); set(gca, 'YScale', 'log');
xlabel('Frequency [Hz]');
ylabel('Compliance - Frobenius Norm');
end

84
src/computeTransmissibility.m Normal file
View File

@@ -0,0 +1,84 @@
function [T, T_norm, freqs] = computeTransmissibility(args)
% computeTransmissibility -
%
% Syntax: [T, T_norm, freqs] = computeTransmissibility(args)
%
% Inputs:
% - args - Structure with the following fields:
% - plots [true/false] - Should plot the transmissilibty matrix and its Frobenius norm
% - freqs [] - Frequency vector to estimate the Frobenius norm
%
% Outputs:
% - T [6x6 ss] - Transmissibility matrix
% - T_norm [length(freqs)x1] - Frobenius norm of the Transmissibility matrix
% - freqs [length(freqs)x1] - Frequency vector in [Hz]
arguments
args.plots logical {mustBeNumericOrLogical} = false
args.freqs double {mustBeNumeric, mustBeNonnegative} = logspace(1,4,1000)
end
freqs = args.freqs;
%% Options for Linearized
options = linearizeOptions;
options.SampleTime = 0;
%% Name of the Simulink File
mdl = 'stewart_platform_model';
%% Input/Output definition
clear io; io_i = 1;
io(io_i) = linio([mdl, '/Disturbances/D_w'], 1, 'openinput'); io_i = io_i + 1; % Base Motion [m, rad]
io(io_i) = linio([mdl, '/Absolute Motion Sensor'], 1, 'openoutput'); io_i = io_i + 1; % Absolute Motion [m, rad]
%% Run the linearization
T = linearize(mdl, io, options);
T.InputName = {'Wdx', 'Wdy', 'Wdz', 'Wrx', 'Wry', 'Wrz'};
T.OutputName = {'Edx', 'Edy', 'Edz', 'Erx', 'Ery', 'Erz'};
p_handle = zeros(6*6,1);
if args.plots
fig = figure;
for ix = 1:6
for iy = 1:6
p_handle((ix-1)*6 + iy) = subplot(6, 6, (ix-1)*6 + iy);
hold on;
plot(freqs, abs(squeeze(freqresp(T(ix, iy), freqs, 'Hz'))), 'k-');
set(gca, 'XScale', 'log'); set(gca, 'YScale', 'log');
if ix < 6
xticklabels({});
end
if iy > 1
yticklabels({});
end
end
end
linkaxes(p_handle, 'xy')
xlim([freqs(1), freqs(end)]);
ylim([1e-5, 1e2]);
han = axes(fig, 'visible', 'off');
han.XLabel.Visible = 'on';
han.YLabel.Visible = 'on';
ylabel(han, 'Frequency [Hz]');
xlabel(han, 'Transmissibility [m/m]');
end
T_norm = zeros(length(freqs), 1);
for i = 1:length(freqs)
T_norm(i) = sqrt(trace(freqresp(T, freqs(i), 'Hz')*freqresp(T, freqs(i), 'Hz')'));
end
T_norm = T_norm/sqrt(6);
if args.plots
figure;
plot(freqs, T_norm)
set(gca, 'XScale', 'log'); set(gca, 'YScale', 'log');
xlabel('Frequency [Hz]');
ylabel('Transmissibility - Frobenius Norm');
end

10
src/initializeGround.m
View File

@@ -6,17 +6,19 @@ function [ground] = initializeGround(args)
% Inputs:
% - args - Structure with the following fields:
% - type - 'none', 'solid', 'flexible'
% - rot_point [3x1] - Rotation point for the ground motion [m]
% - K [3x1] - Translation Stiffness of the Ground [N/m]
% - C [3x1] - Translation Damping of the Ground [N/(m/s)]
%
% Outputs:
% - ground - Struture with the following properties:
% - type - 1 (none), 2 (solid), 3 (flexible)
% - type - 1 (none), 2 (rigid), 3 (flexible)
% - K [3x1] - Translation Stiffness of the Ground [N/m]
% - C [3x1] - Translation Damping of the Ground [N/(m/s)]
arguments
args.type char {mustBeMember(args.type,{'none', 'solid', 'flexible'})} = 'none'
args.type char {mustBeMember(args.type,{'none', 'rigid', 'flexible'})} = 'none'
args.rot_point (3,1) double {mustBeNumeric} = zeros(3,1)
args.K (3,1) double {mustBeNumeric, mustBeNonnegative} = 1e8*ones(3,1)
args.C (3,1) double {mustBeNumeric, mustBeNonnegative} = 1e1*ones(3,1)
end
@@ -24,7 +26,7 @@ end
switch args.type
case 'none'
ground.type = 1;
case 'solid'
case 'rigid'
ground.type = 2;
case 'flexible'
ground.type = 3;
@@ -32,3 +34,5 @@ end
ground.K = args.K;
ground.C = args.C;
ground.rot_point = args.rot_point;

8
src/initializePayload.m
View File

@@ -5,7 +5,7 @@ function [payload] = initializePayload(args)
%
% Inputs:
% - args - Structure with the following fields:
% - type - 'none', 'solid', 'flexible', 'cartesian'
% - type - 'none', 'rigid', 'flexible', 'cartesian'
% - h [1x1] - Height of the CoM of the payload w.r.t {M} [m]
% This also the position where K and C are defined
% - K [6x1] - Stiffness of the Payload [N/m, N/rad]
@@ -15,7 +15,7 @@ function [payload] = initializePayload(args)
%
% Outputs:
% - payload - Struture with the following properties:
% - type - 1 (none), 2 (solid), 3 (flexible)
% - type - 1 (none), 2 (rigid), 3 (flexible)
% - h [1x1] - Height of the CoM of the payload w.r.t {M} [m]
% - K [6x1] - Stiffness of the Payload [N/m, N/rad]
% - C [6x1] - Stiffness of the Payload [N/(m/s), N/(rad/s)]
@@ -23,7 +23,7 @@ function [payload] = initializePayload(args)
% - I [3x3] - Inertia matrix for the Payload [kg*m2]
arguments
args.type char {mustBeMember(args.type,{'none', 'solid', 'flexible', 'cartesian'})} = 'none'
args.type char {mustBeMember(args.type,{'none', 'rigid', 'flexible', 'cartesian'})} = 'none'
args.K (6,1) double {mustBeNumeric, mustBeNonnegative} = 1e8*ones(6,1)
args.C (6,1) double {mustBeNumeric, mustBeNonnegative} = 1e1*ones(6,1)
args.h (1,1) double {mustBeNumeric, mustBeNonnegative} = 100e-3
@@ -34,7 +34,7 @@ end
switch args.type
case 'none'
payload.type = 1;
case 'solid'
case 'rigid'
payload.type = 2;
case 'flexible'
payload.type = 3;