A stand-alone peristaltic micropump based on piezoelectric actuation

Area of Science:

• Microfluidics and MEMS (Micro-Electro-Mechanical Systems)
• Electrical Engineering and Control Systems
• Biomedical Engineering

Background:

• Portable micropump design is hindered by bulky driving equipment.
• Existing piezoelectric micropumps require integrated, compact driving circuits for portability.

Purpose of the Study:

• To develop a self-contained, portable peristaltic micropump system using piezoelectric actuation.
• To investigate the impact of different multi-phase actuation sequences (3-, 4-, and 6-phase) on micropump performance.

Main Methods:

• Designed and constructed a battery-based driving circuit featuring an ATmega 8535 microprocessor, DC-DC converter, amplifiers, and control modules.
• Generated programmable step-function signals (up to 228 V(pp), 10 Hz-100 kHz) for piezoelectric actuation.
• Evaluated pump performance (diaphragm dynamics, flow rate, back pressure, power consumption) under various actuation sequences.

Main Results:

• The system is portable (22 x 12.8 x 9 cm) and programmable.
• The 6-phase actuation sequence demonstrated superior performance over 3- and 4-phase sequences.
• Maximum performance achieved: 36.8 microl/min flow rate and 520 Pa back pressure using deionized water at 100 V(pp) and 700 Hz.

Conclusions:

• The developed stand-alone micropump system effectively addresses the challenge of portable micropump design.
• Multi-phase actuation sequences significantly influence micropump performance, with 6-phase offering optimal results.
• This system provides a viable solution for portable fluid handling applications requiring precise control.