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| 84 | + <h1 class="title is-1 publication-title">PV-OSIMr: A Lowest Order Complexity Algorithm for Computing the Delassus Matrix</h1> |
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| 86 | + <span class="author-block"> |
| 87 | + <a href="https://www.ajaysathya.com">Ajay Suresha Sathya</a><sup>1</sup>,</span> |
| 88 | + <span class="author-block"> |
| 89 | + <a href="https://scholar.google.com/citations?user=ZgAnArUAAAAJ&hl">Wilm Decré</a><sup>2</sup>,</span> |
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| 91 | + <a href="https://scholar.google.com/citations?user=X_fnO1YAAAAJ&hl">Jan Swevers</a><sup>2</sup>,</span> |
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| 99 | + <span class="author-block"><sup>1</sup> Willow, Inria, DI-ENS Paris, PSL University, 75006 Paris, France. </span> |
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| 103 | + <span class="author-block"> <sup>2</sup> Division of Robotics, Automation and Mechatronics, Department of Mechanical Engineering, KU |
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| 191 | + <h2 class="title is-3">Abstract</h2> |
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| 193 | + <p> |
| 194 | + We present PV-OSIMr, an efficient algorithm for computing the Delassus matrix (also known as the inverse operational space inertia matrix) for a kinematic tree, with the lowest order computational complexity known in literature. PV-OSIMr is derived by optimizing the recently proposed PV-OSIM algorithm using the compositionality of the force and motion propagators. It has a computational complexity of $O(n+m^2)$ compared to $O(n+m^2d)$ of the PV-OSIM algorithm and $O(n+md+m^2)$ of the extended force propagator algorithm (EFPA), where $n$ is the number of joints, $m$ is the number of constraints and $d$ is the depth of the kinematic tree. Since the Delassus matrix is an $m×m$ sized matrix and its computation must consider all the n joints, PV-OSIMr's asymptotic computational complexity is optimal. We further benchmark our algorithm and find it to be often more efficient than the PV-OSIM and EFPA in practice. |
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| 256 | + <h2 class="title">BibTeX</h2> |
| 257 | + <pre><code>@ARTICLE{sathya_pvosimr_2024, |
| 258 | + author={Sathya, Ajay Suresha and Decré, Wilm and Swevers, Jan}, |
| 259 | + journal={IEEE Robotics and Automation Letters}, |
| 260 | + title={PV-OSIMr: A Lowest Order Complexity Algorithm for Computing the Delassus Matrix}, |
| 261 | + year={2024}, |
| 262 | + volume={9}, |
| 263 | + number={11}, |
| 264 | + pages={10224-10231}, |
| 265 | + keywords={Heuristic algorithms;Force;Kinematics;Aerospace electronics;Robot kinematics;End effectors;Computational complexity;Computational efficiency;Dynamics;multi-contact whole-body motion planning and control;whole-body motion planning and control}, |
| 266 | + doi={10.1109/LRA.2024.3469829}} |
| 267 | + </code></pre> |
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