This is my solution for mounting vive trackers on human body.
Wide belt was taken from here https://www.aliexpress.com/item/33039087281.html
(one piece used for hip belt and another one is cut in half for using on both legs)
or you can use ordinary flexible belt from a clothing store.
And narrow bands to keep trackers in place are just cheap elastic bands from a hardware store.
The length of the elastic should be 50 cm (19.7 inch). And the two ends are sewn together on the back.
Layer: 0.2 or less
Infill: 20 or more
Adhesion: No, Skirt or Brim (if you have problem with sticking to the bed)
Printed in PLA with temp 210/60 ºC at speed 60 mms