Add two reference

org/bibliography.org

@@ -46,6 +46,8 @@ Things to add:
 - cite:beijen18_exper_estim_trans_matric_indus
 - cite:xie17_model_contr_hybrid_passiv_activ
 - cite:chi15_desig_exper_study_vcm_based
+- cite:guo08_cascad_contr_hydraul_driven_paral
+- cite:zheng18_stewar_isolat_with_high_static
 
 * Books
 |                                                        | <c>  |

org/control-tracking.org

@@ -610,7 +610,7 @@ This will simplify the design of the controller as all the elements of the diago
 #+end_src
 
 #+name: fig:plant_centralized_L
-#+caption: Diagonal and off-diagonal elements of the plant $\bm{K}\bm{G}$ ([[./figs/plant_centralized_L.png][png]], [[./figs/plant_centralized_L.pdf][pdf]])
+#+caption: Diagonal and off-diagonal elements of the plant $\bm{J}\bm{G}$ ([[./figs/plant_centralized_L.png][png]], [[./figs/plant_centralized_L.pdf][pdf]])
 [[file:figs/plant_centralized_L.png]]
 
 We can see that this *totally decouples the system at low frequency*.

org/control-vibration-isolation.org

@@ -39,17 +39,6 @@
 :END:
 
 * Introduction                                                        :ignore:
-Control architectures can be divided in different ways.
-
-It can depend on the sensor used:
-- Sensors located in each strut: relative motion, force sensor, inertial sensor
-- Sensors measuring the relative motion between the fixed base and the mobile platform
-- Inertial sensors located on the mobile platform
-
-It can also depends on the control objective:
-- Reference Tracking
-- Active Damping
-- Vibration Isolation
 
 * HAC-LAC (Cascade) Control - Integral Control
 ** Introduction

org/ref.bib

@@ -1330,3 +1330,33 @@
   url             = {https://doi.org/10.1016/j.actaastro.2020.02.033},
   tags            = {parallel robot},
 }
+
+@article{guo08_cascad_contr_hydraul_driven_paral,
+  author          = {HongBo Guo and YongGuang Liu and GuiRong Liu and HongRen
+                  Li},
+  title           = {Cascade Control of a Hydraulically Driven 6-dof Parallel
+                  Robot Manipulator Based on a Sliding Mode},
+  journal         = {Control Engineering Practice},
+  volume          = 16,
+  number          = 9,
+  pages           = {1055-1068},
+  year            = 2008,
+  doi             = {10.1016/j.conengprac.2007.11.005},
+  url             = {https://doi.org/10.1016/j.conengprac.2007.11.005},
+  tags            = {parallel robot},
+}
+
+@article{zheng18_stewar_isolat_with_high_static,
+  author          = {Yisheng Zheng and Qingpin Li and Bo Yan and Yajun Luo and
+                  Xinong Zhang},
+  title           = {A Stewart Isolator With High-Static-Low-Dynamic Stiffness
+                  Struts Based on Negative Stiffness Magnetic Springs},
+  journal         = {Journal of Sound and Vibration},
+  volume          = 422,
+  number          = {nil},
+  pages           = {390-408},
+  year            = 2018,
+  doi             = {10.1016/j.jsv.2018.02.046},
+  url             = {https://doi.org/10.1016/j.jsv.2018.02.046},
+  tags            = {parallel robot},
+}