design and evaluation of syringe mechanisms for central venous catheterization training

open_access
Open Access
Author:
Kaul, Aayod
Area of Honors:
Mechanical Engineering
Degree:
Bachelor of Science
Document Type:
Thesis
Thesis Supervisors:
Jason Zachary Moore, Thesis Supervisor
Yuan Xuan, Thesis Honors Advisor
Scarlett Miller, Thesis Supervisor
Keywords:
medical devices
simulation-based training
central venous catheterization
linear motion compliant mechanisms
haptics
Abstract:
This honors thesis discusses the need for and design evolution of a syringe to be used in medical simulation for Central Venous Catheterization (CVC), a common yet complication-prone medical procedure. If medical residents use the simulator, they can practice needle insertion and aspiration in a safe, feedback-driven environment before performing the procedure on patients. The initial phase of this project involved a targeted experiment on the Sensorized Original Syringe (SOS), which featured a spring-based aspiration mechanism and integrated sensors. The experiment assessed both face validity and force feedback performance, revealing issues with mechanical fragility, inconsistent aspiration force, and complex internal assembly. To address these limitations, a new syringe prototype was developed using a compliant serpentine flexure mechanism in place of the spring. An analytical model was constructed to describe the flexure’s force–displacement behavior, and a MATLAB-based parameter tuning script enabled rapid iteration based on stress and motion constraints. This framework lays the groundwork for future machine learning integration to automate compliant mechanism design. The resulting compliant syringe reduced material cost by 36%, improved reliability, and simplified in-house additive manufacturing. While full validation remains future work, this project illustrates how improving the fidelity and design of individual simulator components can enhance procedural training. The tools and methodologies introduced here offer broader applications for developing low-cost, high-performance medical simulation devices.