I recently "stumbled upon" the article
[Pedal coordinates, Dark Kepler and other force problems](http://arxiv.org/abs/1704.00897) by Petr Blaschke from 2017;  further search about *Pedal Coordinates* didn't bring up any other relevant online resources; from the references on [Wolfram Mathworld](http://mathworld.wolfram.com/PedalCoordinates.html) I get the impression, that the topic hasn't been the subject and/or means of mathematical research for some decades.  

<br>

>**Questions:**   

>- where, except in the cited article by Petr Blaschke, have Pedal Coordinates played an important role in recent mathematical publications  

>- have there been attempts to generalize Pedal Coordinates to higher dimensions and/or other numbers besides the reals like e.g. complex numbers