{ "id": "1809.09021", "version": "v1", "published": "2018-09-24T15:54:27.000Z", "updated": "2018-09-24T15:54:27.000Z", "title": "Topological complexity of a fibration", "authors": [ "Petar Pavešić" ], "categories": [ "math.AT" ], "abstract": "We study certain topological problems that are inspired by applications to autonomous robot manipulation. Consider a continuous map $f\\colon X\\to Y$, where $f$ can be a kinematic map from the configuration space $X$ to the working space $Y$ of a robot arm or a similar mechanism. Then one can associate to $f$ a number $\\mathrm{TC}(f)$, which is, roughly speaking, the minimal number of continuous rules that are necessary to construct a complete manipulation algorithm for the device. Examples show that $\\mathrm{TC}(f)$ is very sensitive to small perturbations of $f$ and that its value depends heavily on the singularities of $f$. This fact considerably complicates the computations, so we focus here on estimates of $\\mathrm{TC}(f)$ that can be expressed in terms of homotopy invariants of spaces $X$ and $Y$, or that are valid if $f$ satisfy some additional assumptions like, for example, being a fibration. Some of the main results are the derivation of a general upper bound for $\\mathrm{TC}(f)$, invariance of $\\mathrm{TC}(f)$ with respect to deformations of the domain and codomain, proof that $\\mathrm{TC}(f)$ is a FHE-invariant, and the description of a cohomological lower bound for $\\mathrm{TC}(f)$. Furthermore, if $f$ is a fibration we derive more precise estimates for $\\mathrm{TC}(f)$ in terms of the Lusternik-Schnirelmann category and the topological complexity of $X$ and $Y$. We also obtain some results for the important special case of covering projections.", "revisions": [ { "version": "v1", "updated": "2018-09-24T15:54:27.000Z" } ], "analyses": { "subjects": [ "55M99", "70B15", "68T40" ], "keywords": [ "topological complexity", "complete manipulation algorithm", "general upper bound", "important special case", "kinematic map" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }