Thesis’s Title: Study on the development of a self-propelled capsule robot
Major: Mechanical Engineering Code: 9520103
PhD Candidate: Ngo Quoc Huy
University: Thai Nguyen University of Technology – Thai Nguyen University
Science Instructor: Assoc. Prof. Dr. Nguyen Van Du
The contributions of thesis on science and practice, including:
1. Scientificall
- The dissertation has developed a nonlinear mathematical model that accurately describes and reflects the dynamic characteristics of a capsule system driven by a vibro-impact mechanism.
- Once validated, the mathematical model was applied to in-depth dynamic analysis, serving as a valuable reference framework for subsequent studies on design optimization, control strategies, and functional integration in the development of capsule robots for modern medical endoscopy.
- The dissertation contributes to narrowing the academic gap in the design, realization, and dynamic analysis of millimeter-scale capsule robots, particularly those intended to operate in viscous fluid environments, a topic that has received limited attention in previous research.
- A characteristic parameter, defined as the displacement per excitation cycle (yP), was proposed and experimentally determined to construct bifurcation diagrams illustrating the variation of yP with excitation frequency. This progression map provides a clear visualization of motion behavior, accurately reflects the nonlinear dynamic response, and effectively substitutes traditional methods under noisy experimental conditions.
- The study identified optimal control parameter regions (frequency and duty ratio) within the surveyed parameter space to achieve maximum displacement velocity, thereby establishing a scientific basis for the design and control of capsule robots toward practical applications.
2. Practically
- The dissertation successfully designed, fabricated, and validated a driving system for the smallest active capsule model to date in the field of vibro-impact capsule robots (Ø11 × 30.6 mm), demonstrating significant miniaturization potential compared to previous prototypes.
- A comprehensive integration solution was proposed, encapsulating the power source, actuator, and control circuitry within a constrained space, while eliminating physical wiring through two wireless control methods (Bluetooth and infrared).
- A novel actuation mechanism, the Moving Magnet Actuator (MMA) combined with magnetic springs, was developed, reducing axial length by up to 34.89% compared to the previous version, while enhancing oscillation efficiency and durability.
- An experimental system was established with reliable and flexible data acquisition capability, enabling comprehensive validation of design prototypes and confirming the potential of wireless control technology in the advancement of next-generation capsule endoscopy robots.
- Experimental results demonstrated that the complete capsule can operate continuously for up to 4.8 hours with a 35 mAh battery, opening prospects for integrating additional functional modules such as cameras, illumination, and sensors, thereby contributing to the development of fully active capsules for diagnostic and therapeutic applications in future medicine.
