Dynamic emulation of mechanical loads: an advanced approach

The paper presents an advanced approach, which can be used for the dynamic emulation of both linear and nonlinear mechanical loads. The method can be used for the design and validation of the control algorithms of variable speed and torque drives used in mechatronic applications. The actual mechanism to be controlled is replaced by a dynamometer connected mechanically to the drive system, and the torque demand of the dynamometer is calculated from the closed-loop algorithm, performing a model-tracking control in such a manner that the input/output behaviour of the experimental system resembles that of the drive that would be propelling the actual load. A numerical model of the emulated load is used as a reference model and the impact of the test-rig dynamics is compensated. Additionally, a feedback scheme is used to assure the compensation of unmodelled dynamics. The applied dynamometer is assumed to be torque-controlled with high precision. Algorithms are developed with the use of Matlab/Simulink and experiments are executed with the use of the dSPACE system.