I'm trying to implement this paper:
I'm having a hard time understanding Equation (17), specifically what rk' is and where it came from.
I know that rk is the moment arm (a vector), Pb is a position (vector), jk I think is the position of joint k, and Fb and Tb are vectors calculated by equations (14) and (15). What is rk' though? I don't see any mention of it anywhere in the paper. Some google searches on vector prime notation lead me to believe that a vector with the prime symbol means the vector is tranposed. But I can see the transpose symbol already uses T, so is it really saying that vector rk is tranposed?