A DSP-Based Sensorless Dual-Axis Force-Feedback Control System for PMSM Drives in Industrial Simulation Applications

Abstract

This article presents a dual-degree-of-freedom force-feedback control system featuring a sensorless architecture with real-time torque estimation. The system is developed to reproduce the reaction forces acting on a control stick under diverse operating conditions, thereby achieving irreversible and high-fidelity haptic characteristics. A digital signal processor (DSP) serves as the central controller, integrating a reference model, load control module, and torque estimation algorithm within a closed-loop framework. Dual-axis servo motors coupled with a linkage mechanism enable precise torque feedback control while maintaining stable and natural dynamic responses in both passive and active operation modes. Experimental validation confirms the accuracy of the proposed kinematic and dynamic models, demonstrating that the controller effectively tracks the reference model, and provides realistic boundary feedback at end-stop positions. Compared with conventional fixed force-feedback methods, the proposed approach delivers more refined and immersive haptic responses. The system shows strong potential for applications in flight simulators, training platforms, and human–machine interaction systems requiring high-precision motor control.