Date of Defense
Electrical and Computer Engineering
Dr. Liang Dong
Dr. Brad Bazuin
Stryker Instruments produces heavy-duty, battery-operated surgical power tools for use in orthopedic surgeries. These tools are used to remove bone of various densities. As a result of this application, the power draw from the battery is very dynamic. A portable, wireless data acquisition (DAQ) system was designed in order to monitor and study the real-time characteristics of the tool's power consumption. The system was designed on a multi-layer printed circuit board (PCB) that was small enough to fit within the existing rechargeable battery housing.
The general theory of operation describes the collection, transmission and storage of two signals sampled from the battery/tool circuitry. The battery voltage was monitored via a voltage divider across the battery's terminals. This circuit samples the battery's terminal voltage and scales it to an acceptable range for input into the Cypress Programmable System on a Chip (PSoC) microcontroller unit. A hall-effect based current sensor was used to generate a voltage signal proportional to the current flowing in or out of the battery cells. This signal was the second input into the PSoC. The PSoC digitizes these two signals using internal Analog-to-Digital (ATD) converters and relays the data to a Cypress Wireless USB radio chip using a Serial Peripheral Interface (SPI) bus. The radio chip transmits the signals to a receiving station that displays the data on a laptop using a LabVIEW application.
Brier, Shawn; Johnson, Patrick; and Mathsyaraja, Aravind, "Wireless Battery Data Acquisition System" (2006). Honors Theses. 1477.
Honors Thesis-Campus Only