This paper presents systematic rules for determining the minimum set of inertial parameters that are relevant for the dynamic model of serial and tree-like manipulators. In particular, it is shown, starting from the barycentric definition of inertial parameters, that a limited number of additional rules are necessary to obtain this minimum set. Moreover, the value of these parameters can be identified experimentally either from the dynamic model or from a reaction model that relates the robot motion to the reaction forces and torques transmitted to its bedplate.
Raucent, B., & Samin, J.-C. (1994). Minimal Parametrization of Robot Dynamic-models. Mechanics of Structures and Machines, 22(3), 371-396. https://doi.org/10.1080/08905459408905218 (Original work published 1994)