Portable Artificial Kidney (PAK)

This project is funded by National Natural Science Foundation led by Prof. Dayong Gao from the University of Washington, USA. It is designed to make an inexpensive portable artificial kidney (PAK), which would enable end-stage renal disease patients to have blood purification at home. I worked as the project’s co-leader with three group members for one year.

The primary workflow of project is that the PAK can compensate the displacement fluid dynamically based on the adjustment of biosensor and the feedback of the weighing sensor. And thereof, the key issue is how to control this process very precisely. After one year’s persistent research work, our team has finished the prototype’s design, printed circuit board design, microcontrol unit (MCU) control system and the principle verification experiments.

I accomplished almost the whole coding and debugging job, including:
• Serial Peripheral Interface (SPI) communication with sub-MCU
• Serial port communication with weighing sensors and air detection sensor
• Control of peristaltic pumps and electromagnetic valves
• Touchable interactive LCD driver
• Design the proportion integration differentiation (PID) control algorithm for the whole system

In this project, I mainly program under the Silicon IDE environment with C language. I have taught myself many communication protocols like serial port (RS232) and SPI, PCB design skills using the Altium Designer software.

Figure 1. Prototype of Portable Artificial Kidney

Written on July 1, 2014