Open Access

ARTICLE

Contact Force Tracking in Robotics Using Reference-Dependent Constant Impedance Control

Abubaker Ahmed¹, Hosham Wahballa^2,*, AlaEldin Awouda³, Arafat Abdulgader Mohammed Elhag⁴, Ahmed Hamza Osman⁵, Mubarak Himmat⁶

1 School of Automation Engineering, Wuxi University, Wuxi, 214000, China
2 School of Mechanical and Electrical Engineering, Quanzhou University of Information Engineering, Fujian, 362000, China
3 Mechanical Engineering Department, College of Engineering, University of Bisha, Bisha, Saudi Arabia
4 Department of Computer and Information System, Bisha Applied College, University of Bisha, Bisha, Saudi Arabia
5 Department of Information Systems, Faculty of Computing and Information Technology in Rabigh, King Abdulaziz University, Jeddah, 21911, Saudi Arabia
6 Horizon University College, School of Computing, Emirate of Ajman, United Arab Emirates

* Corresponding Author: Hosham Wahballa. Email:

Computer Modeling in Engineering & Sciences 2026, 148(2), 44 https://doi.org/10.32604/cmes.2026.084395

Received 21 April 2026; Accepted 11 August 2026; Issue published 28 August 2026

Abstract

Accurate force regulation is essential in robotic contact tasks such as polishing, grinding, and assembly. However, conventional impedance controllers often exhibit limited force-tracking accuracy, while adaptive methods require high tuning effort and computational cost. To address these issues, this paper proposes a Constant Impedance Force Controller (CIFC) based on a Force Reference Dependent Impedance (F_RDI) model, which is developed and validated through computer modeling and simulation. Robot environment interaction is computationally modeled as a mass damper spring system, and a position-based impedance framework is employed to regulate force deviations. A compensation signal derived from the F_RDI stiffness and damping terms reduces tracking errors while preserving constant impedance characteristics. Stability is proven using Lyapunov analysis. Numerical simulations and experimental validation demonstrate that the proposed method achieves robust force tracking under multi-source uncertainties on ramp, curved, and complex surfaces. The CIFC achieves an average force-tracking RMS error of 0.15 N in simulation, compared with 0.11–0.19 N for the benchmark methods. Experimentally, RMS errors range from 0.24 to 0.52 N under reference forces of 5–15 N on curved and complex surfaces, with maximum deviations of ±0.35 and ±0.50 N, respectively. These results confirm the effectiveness of the proposed modeling and simulation framework, demonstrating improved robustness and tracking consistency over conventional impedance control.

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Keywords

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