Omega used to sell load bolts that were basically a hollow bolt with a strain gauge inside. Sort of like this: https://tml.jp/e/product/strain_gauge/btm_list.ht

Omega used to sell load bolts that were basically a hollow bolt with a strain gauge inside. Sort of like this: https://tml.jp/e/product/strain_gauge/btm_list.html#:~:text=series%20BTM%2FBTMC-,Bolt%20strain%20gauge%20series%20BTM%2FBTMC,mounted%20on%20the%20bolt%20surface https://tml.jp/e/product/strain_gauge/btm_list.html#:~:text=.... If you need that kind of thing, a wireless version would be great. I'm torn between kicking myself for not having thought of it and skepticism over the size of their market. Here are their US patents: https://patents.google.com/patent/US10066930B2 https://patents.google.com/patent/US10066930B2 https://patents.google.com/patent/US11149777B2 https://patents.google.com/patent/US11149777B2