1. ABSTRACT About half a million premature births – one- eighth of all live births – occur in the United States each year. Researchers at the Children’s Hospital of Philadelphia (CHOP) and University of Pennsylvania School of Nursing are currently analyzing the feeding behaviors of these premature babies. A prototype of the NeoNur has been developed to measure, process and store sucking pressures. Basic behavioral characteristics, such as maximum sucking pressure and number of sucking bursts, can be extracted from this raw data and viewed immediately after the feeding session. The raw data can also be uploaded to a PC for further analysis. The NeoNur design is simpler and more intuitive than the current CHOP system, and significantly decreases the time needed to assemble, disassemble and clean the apparatus. NeoNur: A Feeding Apparatus for Premature Neonates CURRENT SYSTEM AT CHOP Dimensions of Feeding Apparatus: 7.5” x 1.5” Dimensions of Processor: 13.0” x 7.0” x 4.3” Total Volume of Device: 386.8 cubic inches Time for Assembly, Disassembly and Cleaning: Approximately 35 minutes Feeding Apparatus Data Processor NEONUR SPECIFICATIONS Dimensions of Feeding Apparatus: 8.0” x 2.0” Total Volume of Device: 25.1 cubic inches Time for Assembly, Disassembly and Cleaning: Approximately 10 minutes Average Current Consumption: 3 mAh Average Battery Life: ~53 hrs (1/3N Lithium) OVERALL SYSTEM ADC EEPROM Flash Memory Chip Processor PC Reference Chip Instrumentation Amplifier Pressure Sensor (0.066 - 0.990 V) Microcontroller Via USART Negative Pressure (20 - 300 mmHg expected) (0.33 - 4.95 mV) 1.35 V All components are connected to a 3.0V battery. DATA ANALYSIS Analysis on the data samples includes calculating the number of pulses, number of bursts, maximum burst duration, maximum pressure of a suck and average burst duration. Threshold Level – Pressures greater than this are considered part of a pulse 160 150 140 130 120 110 100 90 80 70 60 50 40 30 20 0 -20 -40 Pressure (mmHg) Time Pulses Burst Test Output for Data Analysis Code Threshold level set to 20 mmHg Correct analysis performed, as shown by plotting output points ‘Location in Code’. Sample Number over Time HARDWARE PIC16F690 Microcontroller REF2912A Reference Chip S25FL016A Flash Memory INA122 Instrumentation Amplifier TTL-232R-3V3 USB-Serial Converter MPX2300DT1 Pressure Sensor Bursts SOFTWARE The two software components consist of code in the microcontroller and the code in the graphical user interface (GUI). The microcontroller controls the device, given user input through the GUI. Through the interface, the user can connect the NeoNur with the PC through a selected USB port, as well as send instructions such as Calibrate, Start Test, End Test and Save Data to PC. TEAM #1 PROJECT DEMO: April 24, 2008 RCA Lab, Moore Building 10:30am, 11:30am, 1:30pm, 2:00pm, 2:30pm AUTHORS: Leslie Chen (CTE ’08) Preeti Rajendran (EE ‘08) ADVISOR: Dr. Jay Zemel Feeding Apparatus Data Processor User Commands Instructions for GUI – User can repeatedly click button to display more instructions Graphical User Interface Analyze Data and Convert to Pressure Values User Input from GUI Data from ADC Unit of Microcontroller Read Data from Flash Memory and Send to PC Calibrate Begin Test Download Data No End? Write to Flash Memory Store Data in PC Yes Store Current Pressure Software Flow for Microcontroller Code Feedback on Program Status