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

Prealocate some parameters for speed

Browse Source
This commit is contained in:
Thomas Dehaeze 2018-05-03 18:20:07 +02:00
parent 6e4d033fd2
commit 0cca3b7b53
1 changed files with 27 additions and 15 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

42
stewart_init.m
View File

@ -6,21 +6,24 @@ clc;
%%
run stewart_parameters.m
%%
%% Define some constant values
deg2rad = pi/180;
x_axis = [1 0 0];
y_axis = [0 1 0];
z_axis = [0 0 1];
% Connection points on base and top plate w.r.t. World frame at the center
% of the base plate
pos_base = [];
pos_top = [];
%% Connection points on base and top plate w.r.t. World frame at the center of the base plate
pos_base = zeros(6, 3);
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
radius_b = BP.leg.rad*0.001; % rayon emplacement support base
radius_t = TP.leg.rad*0.001; % top radius in meters
for i = 1:3
% base points
angle_m_b = (2*pi/3)* (i-1) - alpha_b;
@ -35,16 +38,18 @@ for i = 1:3
pos_top(2*i-1,:) = [radius_t*cos(angle_m_t), radius_t*sin(angle_m_t), height];
pos_top(2*i,:) = [radius_t*cos(angle_p_t), radius_t*sin(angle_p_t), height];
end
% permute pos_top points so that legs are end points of base and top points
pos_top = [pos_top(6,:); pos_top(1:5,:)]; %6th point on top connects to 1st on bottom
pos_top_tranform = pos_top - height*[zeros(6, 2),ones(6, 1)];
% Compute points w.r.t. to the body frame in a 3x6 matrix
%% Compute points w.r.t. to the body frame in a 3x6 matrix
body_pts = pos_top' - height*[zeros(2,6);ones(1,6)];
% leg vectors
%% leg vectors
legs = pos_top - pos_base;
leg_length = [ ];
leg_vectors = [ ];
leg_length = zeros(6, 1);
leg_vectors = zeros(6, 3);
for i = 1:6
leg_length(i) = norm(legs(i,:));
leg_vectors(i,:) = legs(i,:) / leg_length(i);
@ -52,19 +57,26 @@ end
Leg.lenght = 1000*leg_length(1)/1.5;
% Calculate revolute and cylindrical axes
%% Calculate revolute and cylindrical axes
rev1 = zeros(6, 3);
rev2 = zeros(6, 3);
rev3 = zeros(6, 3);
rev4 = zeros(6, 3);
cyl1 = zeros(6, 3);
for i = 1:6
rev1(i,:) = cross(leg_vectors(i,:), z_axis);
rev1(i,:) = rev1(i,:) / norm(rev1(i,:));
rev3(i,:) = rev1(i,:);
rev2(i,:) = - cross(rev1(i,:), leg_vectors(i,:));
rev2(i,:) = rev2(i,:) / norm(rev2(i,:));
cyl1(i,:) = leg_vectors(i,:);
rev3(i,:) = rev1(i,:);
rev4(i,:) = rev2(i,:);
cyl1(i,:) = leg_vectors(i,:);
end
% Coordinate systems
%% Coordinate systems
lower_leg = struct('origin', [0 0 0], 'rotation', eye(3), 'end_point', [0 0 0]);
upper_leg = struct('origin', [0 0 0], 'rotation', eye(3), 'end_point', [0 0 0]);
@ -77,9 +89,9 @@ for i = 1:6
upper_leg(i).rotation = [rev1(i,:)', rev2(i,:)', cyl1(i,:)'];
end
% Position Matrix
%% Position Matrix
M_pos_base = pos_base + (height+(TP.thickness+Leg.sphere.top+SP.thickness.top+stewart.jacobian)*1e-3)*[zeros(6, 2),ones(6, 1)];
% Compute Jacobian Matrix
%% Compute Jacobian Matrix
J = getJacobianMatrix(leg_vectors, M_pos_base);