Wireless-Controlled Capsule Robots: A Novel Design and Experimental Validation

Document Type : Research Paper

Authors
Tien–Dat Hoang Hoang 1
Van–Du Nguyen 2
Ky–Thanh Ho 2
Ngoc–Hung Chu 3
Quoc–Huy Ngo 2
1 School of Mechanical and Automotive Engineering (SMAE), Ha Noi University of Industry, Ha Noi City, 100000, Viet Nam
2 Department of Mechanical Engineering, Thai Nguyen University of Technology (TNUT), Thai Nguyen City,250000, Viet Nam
3 Thai Nguyen University of Economics-Technology, Thai Nguyen City, 250000, Viet Nam
10.22055/jacm.2025.48223.5072
Abstract
Wireless capsule robots represent a rapidly advancing area of biomedical engineering, with various designs targeting challenges in movement control, power transmission, and functionality within the gastrointestinal tract. This paper presents a wireless-controlled capsubot by integrating an internal lithium battery and a Bluetooth amplification circuit, enabling wireless communication with an external USB Bluetooth transmitter to eliminate physical signal wires. New physical and mathematical models were developed by incorporating drag and buoyant force when capsubot moves in the fluid environment. An experimental system was built to verify the wireless control capabilities of capsubot in the dry friction condition. Comparative analysis of experimental results and numerical simulation data by the XPPauto software revealed a consistent correlation, indicating the accuracy of the mathematical model and the reliability of Bluetooth wireless control solutions for the proposed capsule. Experimental investigations demonstrated that the excitation frequency directly affects the capsubot’s movement speed. The capsubot can completely reverse its direction by altering the external excitation signals from sine waves to square wave and vice versa or change the control parameters including frequency f and excitation force intensity Fm from outside the capsule. Bifurcation diagram analysis, phase trajectory, and Poincaré section techniques were employed to evaluate the dynamic behavior and stability of the capsule system. The influence of frequency, excitation signal type and fluids properties on capsule performance was also evaluated by numerical method. These results serve as a foundation for optimizing operational parameters and conducting experiments for the capsule under more realistic conditions in the future.
Keywords
Capsule robot
Capsubot
Vibro-impact
Vibration driven locomotion systems
Wireless control
Endoscopic capsules
Subjects

Publisher’s Note Shahid Chamran University of Ahvaz remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

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Journal of Applied and Computational Mechanics
Volume 12, Issue 1
Winter 2026
Pages 271-288