The paper deals with the optimal control problem that arises when one studies the 4 sphere artificial swimmer at low Reynolds number. Composed of four spheres at the end of extensible arms, the swimmer is known to be able to swim in all directions and orientations in the 3D space. In this paper, optimal strokes, in terms of the energy expended by the swimmer to reach a prescribed net displacement, are fully described in the regime of small strokes. In particular, we introduce a bivector formalism to model the displacements that turns out to be elegant and practical. Numerical simulations are also provided that confirm the theoretical predictions.
Keywords: Low Reynolds number swimming, optimal strokes, periodic control
@article{MSIA_2022__11_1_167_0, author = {Fran\c{c}ois Alouges and Aline Lefebvre-Lepot and Philipp Weder}, title = {Optimal strokes for the 4-sphere swimmer at low {Reynolds} number in the regime of small deformations}, journal = {MathematicS In Action}, pages = {167--192}, publisher = {Soci\'et\'e de Math\'ematiques Appliqu\'ees et Industrielles}, volume = {11}, number = {1}, year = {2022}, doi = {10.5802/msia.23}, language = {en}, url = {https://msia.centre-mersenne.org/articles/10.5802/msia.23/} }
TY - JOUR AU - François Alouges AU - Aline Lefebvre-Lepot AU - Philipp Weder TI - Optimal strokes for the 4-sphere swimmer at low Reynolds number in the regime of small deformations JO - MathematicS In Action PY - 2022 SP - 167 EP - 192 VL - 11 IS - 1 PB - Société de Mathématiques Appliquées et Industrielles UR - https://msia.centre-mersenne.org/articles/10.5802/msia.23/ DO - 10.5802/msia.23 LA - en ID - MSIA_2022__11_1_167_0 ER -
%0 Journal Article %A François Alouges %A Aline Lefebvre-Lepot %A Philipp Weder %T Optimal strokes for the 4-sphere swimmer at low Reynolds number in the regime of small deformations %J MathematicS In Action %D 2022 %P 167-192 %V 11 %N 1 %I Société de Mathématiques Appliquées et Industrielles %U https://msia.centre-mersenne.org/articles/10.5802/msia.23/ %R 10.5802/msia.23 %G en %F MSIA_2022__11_1_167_0
François Alouges; Aline Lefebvre-Lepot; Philipp Weder. Optimal strokes for the 4-sphere swimmer at low Reynolds number in the regime of small deformations. MathematicS In Action, Volume 11 (2022) no. 1, pp. 167-192. doi : 10.5802/msia.23. https://msia.centre-mersenne.org/articles/10.5802/msia.23/
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