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< title > Stewart Platforms< / title >
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< h1 class = "title" > Stewart Platforms< / h1 >
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< h2 > Table of Contents< / h2 >
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< li > < a href = "#orgff0bfd7" > 1. Simulink Project (link)< / a > < / li >
< li > < a href = "#org38b9089" > 2. Stewart Platform Architecture Definition (link)< / a > < / li >
< li > < a href = "#orgf1c7b3b" > 3. Simscape Model of the Stewart Platform (link)< / a > < / li >
< li > < a href = "#org369c8bb" > 4. Kinematic Analysis (link)< / a > < / li >
< li > < a href = "#org2e3169e" > 5. Identification of the Stewart Dynamics (link)< / a > < / li >
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< li > < a href = "#org0fdb910" > 6. Control< / a > < / li >
< li > < a href = "#org1f468b1" > 7. Cubic Configuration (link)< / a > < / li >
< li > < a href = "#orga2bd0e9" > 8. Bibliography (link)< / a > < / li >
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The goal of this project is to provide a Matlab/Simscape Toolbox to study Stewart platforms.
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The project is divided into several section listed below.
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< h2 id = "orgff0bfd7" > < span class = "section-number-2" > 1< / span > Simulink Project (< a href = "simulink-project.html" > link< / a > )< / h2 >
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The project is managed with a < b > Simulink Project< / b > .
Such project is briefly presented < a href = "simulink-project.html" > here< / a > .
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< h2 id = "org38b9089" > < span class = "section-number-2" > 2< / span > Stewart Platform Architecture Definition (< a href = "stewart-architecture.html" > link< / a > )< / h2 >
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The way the Stewart Platform is defined is explained < a href = "stewart-architecture.html" > here< / a > .
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All the geometrical parameters are defined including:
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< li > Definition of the location of the frames< / li >
< li > Location/orientation of the limbs< / li >
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< li > Size/inertia of the platforms and the limbs< / li >
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Other parameters are also defined such as:
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< li > Stiffness and damping of the struts< / li >
< li > Rest position of the Stewart platform< / li >
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< h2 id = "orgf1c7b3b" > < span class = "section-number-2" > 3< / span > Simscape Model of the Stewart Platform (< a href = "simscape-model.html" > link< / a > )< / h2 >
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The Stewart Platform is then modeled using < a href = "https://www.mathworks.com/products/simscape.html" > Simscape< / a > .
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The way to model is build and works is explained < a href = "simscape-model.html" > here< / a > .
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< h2 id = "org369c8bb" > < span class = "section-number-2" > 4< / span > Kinematic Analysis (< a href = "kinematic-study.html" > link< / a > )< / h2 >
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From the defined geometry of the Stewart platform, we can perform static analysis such as:
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< li > < b > Jacobian Analysis< / b > that links the velocity of each limb to the velocity of the mobile platform< / li >
< li > < b > Static Forces Analysis< / b > that links the forces applied by each limb to the resulting force/torque applied to the mobile platform< / li >
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From the strut stiffness, we can also perform a < b > Stiffness Analysis< / b > that consists of determining the Stiffness matrix and Compliance matrix of the Stewart platform from the geometry.
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All these analysis are described < a href = "kinematic-study.html" > here< / a > .
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< h2 id = "org2e3169e" > < span class = "section-number-2" > 5< / span > Identification of the Stewart Dynamics (< a href = "identification.html" > link< / a > )< / h2 >
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The Dynamics of the Stewart platform can be identified using the Simscape model.
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It is possible to:
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< li > Determine the dynamics from the actuators to the various sensors included in the Stewart platform< / li >
< li > Extract State Space models for further analysis / control synthesis< / li >
< li > Extract the Resonant Frequencies, Modal Damping, and associated Mode Shapes< / li >
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The code that is used for identification is explained < a href = "identification.html" > here< / a > .
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< h2 id = "org0fdb910" > < span class = "section-number-2" > 6< / span > Control< / h2 >
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The use of active control for Stewart platforms is a wide subject.
Many aspect can be studied.
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The sensors used is of primary important. We can have:
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< li > Sensors located in each strut: relative motion, force sensor, inertial sensor< / li >
< li > Sensors measuring the relative motion between the fixed base and the mobile platform< / li >
< li > Inertial sensors located on the mobile platform< / li >
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The control objective can also vary:
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< li > Reference Tracking< / li >
< li > Active Damping< / li >
< li > Vibration Isolation< / li >
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The Control for Stewart platforms is here studied in the following files:
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< ul class = "org-ul" >
< li > < b > Active Damping< / b > (< a href = "control-active-damping.html" > link< / a > ).
The use of different sensors are compared for active damping:
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< li > Inertial Sensor in each strut or fixed to the mobile platform< / li >
< li > Force Sensor in each strut< / li >
< li > Relative Motion Sensor in each strut< / li >
< / ul > < / li >
< li > < b > Motion Control< / b > (< a href = "control-tracking.html" > link< / a > ).
Different control architectures (centralized and decentralized) are compared for the position control of the Stewart platform.< / li >
< li > < b > Vibration Isolation< / b > (< a href = "control-vibration-isolation.html" > link< / a > )< / li >
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< h2 id = "org1f468b1" > < span class = "section-number-2" > 7< / span > Cubic Configuration (< a href = "cubic-configuration.html" > link< / a > )< / h2 >
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The cubic configuration is a special class of Stewart platform that has interesting properties.
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These properties are studied in < a href = "cubic-configuration.html" > this< / a > document.
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< h2 id = "orga2bd0e9" > < span class = "section-number-2" > 8< / span > Bibliography (< a href = "bibliography.html" > link< / a > )< / h2 >
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Many text books, PhD thesis and articles related to parallel robots and Stewart platforms are gathered in < a href = "bibliography.html" > this< / a > document.
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< div id = "postamble" class = "status" >
< p class = "author" > Author: Dehaeze Thomas< / p >
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< p class = "date" > Created: 2020-08-05 mer. 13:27< / p >
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