.....as a simplified mental picture / abstracțion at : http://www.geocities.ws/iacob_alex/Some_Drafts/text028.JPG (http://www.geocities.ws/iacob_alex/Some_Drafts/text028.JPG)
.....as a variable jointed arm proposal , at : http://www.geocities.ws/iacob_alex/Some_Drafts/text048.jpg (http://www.geocities.ws/iacob_alex/Some_Drafts/text048.jpg)
.....as a possible self rotating spring-mass-spring: https://www.britannica.com/science/spring-force ( next proposal...)
Al_ex