Spur Gears and Leadscrew Based, Efficient and Flexible Infusion System Design

This paper presents the design of an inexpensive infusion system for low and middle-income countries like Pakistan. A flexible improvised design in terms of accuracy and user-interface is presented, based on spur gears and leadscrew. The trade-offs between accuracy and other design parameters such as weight, cost and size are also discussed. A detailed analysis of accuracy dependence on leadscrew pitch and number of teeth of each gear is given. Two prototypes are presented, with and without gearbox. An android application is developed considering widespread use of smartphones. It provides access to internet making it easy to share the data. Several alarms and feedback components have also been added to the system. Final design is efficient in terms of number of hardware components, robustness, portability, cost, power and size achieving an accuracy of 23.7nL per step of the stepper motor with 20cc reservoir.