A Focal Curve Approximation of a Borromini Oval Contour

  • Maja PetrovićEmail author
  • Branko Malešević
  • Radovan Štulić
  • Marko Vučić
  • Đorđe Petrović
  • Radomir Mijailović


In this paper we derive a mathematical procedure for the determination of a Weberian focal curve (of two, three or four collinear foci), as a good fitting curve for the impost of the Dome of San Carlo alle Quatro Fontane by Francesco Borromini. For this research, the usual oval composition of two or more circles, which is a piecewise function having the property of C1 continuity, is substituted with a Weberian differentiable focal curve. The created procedure iteratively determines the position of foci giving the highest possible value of the coefficient of determination for the particular case study.


San Carlo alle Quattro Fontane Weberian focal curve Contour fit 



This research was supported by the Serbian Ministry of Education and Science (Projects no. TR 36042, ON 174032, III 44006, TR 36010 and TR 36022).


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Copyright information

© Kim Williams Books, Turin 2018

Authors and Affiliations

  1. 1.The Faculty of Transport and Traffic EngineeringUniversity of BelgradeBelgradeSerbia
  2. 2.School of Electrical EngineeringUniversity of BelgradeBelgradeSerbia
  3. 3.Faculty of Technical SciencesUniversity of Novi SadNovi SadSerbia

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