260 lines
9.4 KiB
HTML
260 lines
9.4 KiB
HTML
|
<!DOCTYPE html>
|
||
|
<html lang="en">
|
||
|
<head>
|
||
|
<meta charset="utf-8">
|
||
|
<meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1">
|
||
|
<title>A soft 6-axis active vibration isolator - My digital brain</title>
|
||
|
<meta name="renderer" content="webkit" />
|
||
|
<meta name="viewport" content="width=device-width, initial-scale=1, maximum-scale=1"/>
|
||
|
|
||
|
<meta http-equiv="Cache-Control" content="no-transform" />
|
||
|
<meta http-equiv="Cache-Control" content="no-siteapp" />
|
||
|
|
||
|
<meta name="theme-color" content="#f8f5ec" />
|
||
|
<meta name="msapplication-navbutton-color" content="#f8f5ec">
|
||
|
<meta name="apple-mobile-web-app-capable" content="yes">
|
||
|
<meta name="apple-mobile-web-app-status-bar-style" content="#f8f5ec">
|
||
|
|
||
|
|
||
|
<meta name="author" content="
|
||
|
|
||
|
|
||
|
—
|
||
|
|
||
|
Thomas Dehaeze
|
||
|
|
||
|
|
||
|
|
||
|
" /><meta name="description" content="Tags Stewart Platforms, Vibration Isolation Reference (Spanos {\it et al.}, 1995) Author(s) Spanos, J., Rahman, Z., &amp; Blackwood, G. Year 1995 Stewart Platform (Figure 1):
|
||
|
Voice Coil Flexible joints (cross-blades) Force Sensors Cubic Configuration
|
||
|
Figure 1: Stewart Platform
|
||
|
Total mass of the paylaod: 30kg Center of gravity is 9cm above the geometry center of the mount (cube&rsquo;s center?).
|
||
|
Limitation of the Decentralized Force Feedback:" />
|
||
|
<link rel="canonical" href="/paper/spanos95_soft_activ_vibrat_isolat/" />
|
||
|
<link rel="icon" type="image/png" sizes="32x32" href="/favicon-32x32.png">
|
||
|
<link rel="icon" type="image/png" sizes="16x16" href="/favicon-16x16.png">
|
||
|
|
||
|
|
||
|
|
||
|
<link href="/sass/main.min.47a894bd6354cc46903f62433747958dc936e1c95c28a76ac80319bca9708ed1.css" rel="stylesheet">
|
||
|
|
||
|
|
||
|
|
||
|
|
||
|
</head>
|
||
|
<body>
|
||
|
<div id="mobile-navbar" class="mobile-navbar">
|
||
|
<div class="mobile-header-logo">
|
||
|
<a href="/" class="logo">Digital Brain</a>
|
||
|
</div>
|
||
|
<div class="mobile-navbar-icon">
|
||
|
<span></span>
|
||
|
<span></span>
|
||
|
<span></span>
|
||
|
</div>
|
||
|
</div>
|
||
|
<nav id="mobile-menu" class="mobile-menu slideout-menu">
|
||
|
<ul class="mobile-menu-list">
|
||
|
<a href="/">
|
||
|
<li class="mobile-menu-item">Home</li>
|
||
|
</a><a href="/zettels/">
|
||
|
<li class="mobile-menu-item">Zettels</li>
|
||
|
</a><a href="/book/">
|
||
|
<li class="mobile-menu-item">Books</li>
|
||
|
</a><a href="/paper/">
|
||
|
<li class="mobile-menu-item">Papers</li>
|
||
|
</a><a href="/search/">
|
||
|
<li class="mobile-menu-item">Search</li>
|
||
|
</a>
|
||
|
</ul>
|
||
|
</nav>
|
||
|
<div class="container" id="mobile-panel">
|
||
|
<header id="header" class="header">
|
||
|
<div class="logo-wrapper">
|
||
|
<a href="/" class="logo">Digital Brain</a>
|
||
|
</div>
|
||
|
|
||
|
<nav class="site-navbar">
|
||
|
<ul id="menu" class="menu">
|
||
|
<li class="menu-item">
|
||
|
<a class="menu-item-link" href="/">Home</a>
|
||
|
</li><li class="menu-item">
|
||
|
<a class="menu-item-link" href="/zettels/">Zettels</a>
|
||
|
</li><li class="menu-item">
|
||
|
<a class="menu-item-link" href="/book/">Books</a>
|
||
|
</li><li class="menu-item">
|
||
|
<a class="menu-item-link" href="/paper/">Papers</a>
|
||
|
</li><li class="menu-item">
|
||
|
<a class="menu-item-link" href="/search/">Search</a>
|
||
|
</li>
|
||
|
</ul>
|
||
|
</nav>
|
||
|
|
||
|
</header>
|
||
|
|
||
|
<main id="main" class="main">
|
||
|
<div class="content-wrapper">
|
||
|
<div id="content" class="content">
|
||
|
<article class="post">
|
||
|
|
||
|
<header class="post-header">
|
||
|
<h1 class="post-title">A soft 6-axis active vibration isolator</h1>
|
||
|
</header>
|
||
|
|
||
|
<div class="post-toc" id="post-toc">
|
||
|
<h2 class="post-toc-title">Contents</h2>
|
||
|
<div class="post-toc-content">
|
||
|
<nav id="TableOfContents"></nav>
|
||
|
</div>
|
||
|
</div>
|
||
|
<div class="post-content">
|
||
|
<dl>
|
||
|
<dt>Tags</dt>
|
||
|
<dd><a href="/zettels/stewart_platforms/">Stewart Platforms</a>, <a href="/zettels/vibration_isolation/">Vibration Isolation</a></dd>
|
||
|
<dt>Reference</dt>
|
||
|
<dd><sup id="a48f6708d087625a42ca2375407a2bc4"><a href="#spanos95_soft_activ_vibrat_isolat" title="Spanos, Rahman \& Blackwood, A Soft 6-axis Active Vibration Isolator, nil, in in: {Proceedings of 1995 American Control Conference - ACC'95}, edited by (1995)">(Spanos {\it et al.}, 1995)</a></sup></dd>
|
||
|
<dt>Author(s)</dt>
|
||
|
<dd>Spanos, J., Rahman, Z., & Blackwood, G.</dd>
|
||
|
<dt>Year</dt>
|
||
|
<dd>1995</dd>
|
||
|
</dl>
|
||
|
<p><strong>Stewart Platform</strong> (Figure <a href="#org4317d08">1</a>):</p>
|
||
|
<ul>
|
||
|
<li>Voice Coil</li>
|
||
|
<li>Flexible joints (cross-blades)</li>
|
||
|
<li>Force Sensors</li>
|
||
|
<li>Cubic Configuration</li>
|
||
|
</ul>
|
||
|
<p><a id="org4317d08"></a></p>
|
||
|
<figure>
|
||
|
<img src="/ox-hugo/spanos95_stewart_platform.png"
|
||
|
alt="Figure 1: Stewart Platform"/> <figcaption>
|
||
|
<p>Figure 1: Stewart Platform</p>
|
||
|
</figcaption>
|
||
|
</figure>
|
||
|
|
||
|
<p>Total mass of the paylaod: 30kg
|
||
|
Center of gravity is 9cm above the geometry center of the mount (cube’s center?).</p>
|
||
|
<p>Limitation of the <strong>Decentralized Force Feedback</strong>:</p>
|
||
|
<ul>
|
||
|
<li>high frequency pole due to internal resonances of the struts</li>
|
||
|
<li>low frequency zero due to the rotational stiffness of the flexible joints</li>
|
||
|
</ul>
|
||
|
<p>After redesign of the struts:</p>
|
||
|
<ul>
|
||
|
<li>high frequency pole at 4.7kHz</li>
|
||
|
<li>low frequency zero at 2.6Hz but non-minimum phase (not explained).
|
||
|
Small viscous damping material in the cross blade flexures made the zero minimum phase again.</li>
|
||
|
</ul>
|
||
|
<p><a id="org67e505c"></a></p>
|
||
|
<figure>
|
||
|
<img src="/ox-hugo/spanos95_iff_plant.png"
|
||
|
alt="Figure 2: Experimentally measured transfer function from voice coil drive voltage to collocated load cell output voltage"/> <figcaption>
|
||
|
<p>Figure 2: Experimentally measured transfer function from voice coil drive voltage to collocated load cell output voltage</p>
|
||
|
</figcaption>
|
||
|
</figure>
|
||
|
|
||
|
<p>The controller used consisted of:</p>
|
||
|
<ul>
|
||
|
<li>second order low pass filter to gain stabilize the plant at high frequencies and provide steep roll-off</li>
|
||
|
<li>first order lead filter to provide adequate phase margin at the high frequency crossover</li>
|
||
|
<li>first order lag filter to provide adequate phase margin at the low frequency crossover</li>
|
||
|
<li>a first order high pass filter to attenuate the excess gain resulting from the low frequency zero</li>
|
||
|
</ul>
|
||
|
<p>The results in terms of transmissibility are shown in Figure <a href="#orgf128817">3</a>.</p>
|
||
|
<p><a id="orgf128817"></a></p>
|
||
|
<figure>
|
||
|
<img src="/ox-hugo/spanos95_results.png"
|
||
|
alt="Figure 3: Experimentally measured Frobenius norm of the 6-axis transmissibility"/> <figcaption>
|
||
|
<p>Figure 3: Experimentally measured Frobenius norm of the 6-axis transmissibility</p>
|
||
|
</figcaption>
|
||
|
</figure>
|
||
|
|
||
|
<h1 id="bibliography">Bibliography</h1>
|
||
|
<p><a id="spanos95_soft_activ_vibrat_isolat"></a>Spanos, J., Rahman, Z., & Blackwood, G., <em>A soft 6-axis active vibration isolator</em>, In , Proceedings of 1995 American Control Conference - ACC'95 (pp. ) (1995). : . <a href="#a48f6708d087625a42ca2375407a2bc4">↩</a></p>
|
||
|
|
||
|
</div>
|
||
|
|
||
|
<footer class="post-footer">
|
||
|
|
||
|
<nav class="post-nav">
|
||
|
<a class="prev" href="/paper/preumont07_six_axis_singl_stage_activ/">
|
||
|
<i class="iconfont icon-left"></i>
|
||
|
<span class="prev-text nav-default">A six-axis single-stage active vibration isolator based on stewart platform</span>
|
||
|
<span class="prev-text nav-mobile">Prev</span>
|
||
|
</a>
|
||
|
<a class="next" href="/paper/devasia07_survey_contr_issues_nanop/">
|
||
|
<span class="next-text nav-default">A survey of control issues in nanopositioning</span>
|
||
|
<span class="next-text nav-mobile">Next</span>
|
||
|
<i class="iconfont icon-right"></i>
|
||
|
</a>
|
||
|
</nav>
|
||
|
</footer>
|
||
|
</article>
|
||
|
</div>
|
||
|
</div>
|
||
|
</main>
|
||
|
|
||
|
<footer id="footer" class="footer">
|
||
|
<div class="social-links">
|
||
|
<a href="mailto:dehaeze.thomas@gmail.com" class="iconfont icon-email" title="email"></a>
|
||
|
<a href="https://github.com/tdehaeze/" class="iconfont icon-github" title="github"></a>
|
||
|
<a href="/index.xml" type="application/rss+xml" class="iconfont icon-rss" title="rss"></a>
|
||
|
</div>
|
||
|
|
||
|
<div class="copyright">
|
||
|
<span class="power-by">
|
||
|
Powered by <a class="hexo-link" href="https://gohugo.io">Hugo</a>
|
||
|
</span>
|
||
|
|
||
|
<span class="copyright-year">
|
||
|
©
|
||
|
2020
|
||
|
<span class="heart">
|
||
|
<i class="iconfont icon-heart"></i>
|
||
|
</span>
|
||
|
<span class="author">Thomas Dehaeze</span>
|
||
|
</span>
|
||
|
</div>
|
||
|
|
||
|
</footer>
|
||
|
|
||
|
<div class="back-to-top" id="back-to-top">
|
||
|
<i class="iconfont icon-up"></i>
|
||
|
</div>
|
||
|
</div>
|
||
|
|
||
|
<script src="https://cdn.jsdelivr.net/npm/jquery@3.2.1/dist/jquery.min.js" integrity="sha256-hwg4gsxgFZhOsEEamdOYGBf13FyQuiTwlAQgxVSNgt4=" crossorigin="anonymous"></script>
|
||
|
<script src="https://cdn.jsdelivr.net/npm/slideout@1.0.1/dist/slideout.min.js" integrity="sha256-t+zJ/g8/KXIJMjSVQdnibt4dlaDxc9zXr/9oNPeWqdg=" crossorigin="anonymous"></script>
|
||
|
|
||
|
|
||
|
<script type="text/javascript" src="/js/main.4bada4f824623eea2eb7cfd5cf8c1d99c3dd797297e7e8cbc59a41da450bb334.js"></script>
|
||
|
|
||
|
|
||
|
<script type="text/javascript">
|
||
|
window.MathJax = {
|
||
|
loader: {
|
||
|
load: ['[tex]/ams']
|
||
|
},
|
||
|
tex: {
|
||
|
inlineMath: [
|
||
|
['$','$'], ['\\(','\\)']
|
||
|
],
|
||
|
tags: 'ams',
|
||
|
packages: {'[+]': ['ams']},
|
||
|
}
|
||
|
};
|
||
|
</script>
|
||
|
|
||
|
<script async src="https://cdn.jsdelivr.net/npm/mathjax@3/es5/tex-mml-chtml.js" crossorigin="anonymous"></script>
|
||
|
|
||
|
<script src="https://cdnjs.cloudflare.com/ajax/libs/fuse.js/3.2.0/fuse.min.js"></script>
|
||
|
<script src="https://cdnjs.cloudflare.com/ajax/libs/mark.js/8.11.1/jquery.mark.min.js"></script>
|
||
|
<script type="text/javascript" src="/lib/search/search.js"></script>
|
||
|
|
||
|
|
||
|
|
||
|
|
||
|
</body>
|
||
|
</html>
|