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[DONE] Files are now compliant with the new model

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Thomas Dehaeze
2020-02-13 15:48:42 +01:00
parent c947ed116f
commit d12891df43
2 changed files with 68 additions and 63 deletions
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org/kinematic-study.org
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@@ -270,7 +270,7 @@ The relative strut length displacement is shown in Figure [[fig:inverse_kinemati
for i = 1:length(Xrs)
Xr = Xrs(i);
L_approx(:, i) = stewart.J*[Xr; 0; 0; 0; 0; 0;];
L_approx(:, i) = stewart.kinematics.J*[Xr; 0; 0; 0; 0; 0;];
[~, L_exact(:, i)] = inverseKinematics(stewart, 'AP', [Xr; 0; 0]);
end
#+end_src
@@ -321,7 +321,9 @@ The relative strut length displacement is shown in Figure [[fig:inverse_kinemati
[[file:figs/inverse_kinematics_approx_validity_x_translation_relative.png]]
*** Conclusion
#+begin_important
For small wanted displacements (up to $\approx 1\%$ of the size of the Hexapod), the approximate inverse kinematic solution using the Jacobian matrix is quite correct.
#+end_important
* Estimated required actuator stroke from specified platform mobility
:PROPERTIES:
@@ -357,7 +359,7 @@ Let's first define the Stewart platform architecture that we want to study.
stewart = initializeStewartPose(stewart);
stewart = initializeCylindricalPlatforms(stewart);
stewart = initializeCylindricalStruts(stewart);
stewart = initializeStrutDynamics(stewart, 'Ki', 1e6*ones(6,1), 'Ci', 1e2*ones(6,1));
stewart = initializeStrutDynamics(stewart);
stewart = initializeJointDynamics(stewart);
stewart = computeJacobian(stewart);
#+end_src
@@ -378,12 +380,12 @@ As a first estimation, we estimate the needed actuator stroke for "pure" rotatio
We do that using either the Inverse Kinematic solution or the Jacobian matrix as an approximation.
#+begin_src matlab
LTx = stewart.J*[Tx_max 0 0 0 0 0]';
LTy = stewart.J*[0 Ty_max 0 0 0 0]';
LTz = stewart.J*[0 0 Tz_max 0 0 0]';
LRx = stewart.J*[0 0 0 Rx_max 0 0]';
LRy = stewart.J*[0 0 0 0 Ry_max 0]';
LRz = stewart.J*[0 0 0 0 0 Rz_max]';
LTx = stewart.kinematics.J*[Tx_max 0 0 0 0 0]';
LTy = stewart.kinematics.J*[0 Ty_max 0 0 0 0]';
LTz = stewart.kinematics.J*[0 0 Tz_max 0 0 0]';
LRx = stewart.kinematics.J*[0 0 0 Rx_max 0 0]';
LRy = stewart.kinematics.J*[0 0 0 0 Ry_max 0]';
LRz = stewart.kinematics.J*[0 0 0 0 0 Rz_max]';
#+end_src
The obtain required stroke is:
@@ -514,7 +516,7 @@ Let's first define the Stewart platform architecture that we want to study.
stewart = initializeStewartPose(stewart);
stewart = initializeCylindricalPlatforms(stewart);
stewart = initializeCylindricalStruts(stewart);
stewart = initializeStrutDynamics(stewart, 'Ki', 1e6*ones(6,1), 'Ci', 1e2*ones(6,1));
stewart = initializeStrutDynamics(stewart);
stewart = initializeJointDynamics(stewart);
stewart = computeJacobian(stewart);
#+end_src
@@ -547,7 +549,7 @@ For each possible value of $(\theta, \phi)$, we compute the maximum radius $r$ a
Ty = sin(thetas(i))*sin(phis(j));
Tz = cos(thetas(i));
dL = stewart.J*[Tx; Ty; Tz; 0; 0; 0;]; % dL required for 1m displacement in theta/phi direction
dL = stewart.kinematics.J*[Tx; Ty; Tz; 0; 0; 0;]; % dL required for 1m displacement in theta/phi direction
rs(i, j) = max([dL(dL<0)*L_min; dL(dL>0)*L_max]);
end