Development of a measurement robot for identifying all inertia parameters of a rigid body in a single experiment

Standard experiments for identifying inertia parameters of a rigid body only provide a subset of its ten inertia parameters. All of these procedures only use a subset of the information included in the equations of motion of a rigid test body. This application paper discusses the construction and functioning of a laboratory setup (inertia measurement robot) that simultaneously estimates the ten inertia parameters of a rigid body using the complete information hidden in the nonlinear model equations of the test body. The measurement robot has been carefully designed to keep disturbances of the estimation process small. A key construction means to exclude disturbance forces and torques from the measurement chain is to attach a test body to the robot by means of a force-moment sensor. The task has been solved in several steps: mathematical modeling of the spatial equations of motion of a rigid body, representation of the model equations in a form suitable for experimental identification of the ten inertia parameters and for inverse computer simulation of the test body, special design of the measurement robot, experimental analysis, corrections and accuracy test of the force-moment sensor, laboratory experiments for providing test data, and estimation of the inertia parameters. The ten inertia parameters of rigid bodies obtained by the above approach are sufficiently accurate to be used in various applications of industrial practice