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Design and Prototype of a Freshwater Ice Thickness Measuring Device

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Design and Prototype of a Freshwater Ice Thickness Measuring Device Design and Prototype of a Freshwater Ice Thickness Measuring Device A Major Qualifying Project Submitted to the Faculty of WORCESTER POLYTECHNIC INSTITUTE in partial fulfilment of the requirements for the Degree of Bachelor of Science By: Anthony DiBiasio Zoe Eggleston Alexander Grammenos Date: 25 April 2017 Report Submitted to: Prof. Robert Daniello Worcester Polytechnic Institute This report represents work of WPI undergraduate students submitted to the faculty as evidence of a degree requirement. WPI routinely publishes these reports on its web site without editorial or peer review. For more information about the projects program at WPI, see http://www.wpi.edu/Academics/Projects. Abstract In the United States, roughly 3,500 fatal drowning incidents are reported each year. A portion of which consist of cold water instances where the ice thickness of a frozen body of water is insufficient to support the weight of the individual, causing the ice underneath them to break. The proposed electromechanical design is an autonomous thermistor chain which can be used to relay the temperature profile of a body of water to an onshore receiver. The device utilizes thermistors to measure the temperature of water/ice at various depths to quantify the ice thickness of a body of freshwater. The device aims to increase ice safety by eliminating the need for on ice tests. After designing and manufacturing a thermistor chain prototype, the team created an insulated testing apparatus to simulate the freezing process of a body of freshwater such as a lake or pond. The data collected provides a representation of the accuracy of the device and serves as proof of concept. i Table of Contents Abstract ........................................................................................................................................... ii Table of Contents .......................................................................................................................... iiii Table of Figures ............................................................................................................................ vv List of Tables .............................................................................................................................. vivi 1.0 Introduction ............................................................................................................................. 77 2.0 Background ............................................................................................................................. 99 2.1 Fatality Statistics/Safety ...................................................................................................... 99 2.1.1 Ice Related Incidents .................................................................................................... 99 2.1.2 Correlation of Ice Thickness and Seasons .................................................................... 99 2.2 Ice Properties ................................................................................................................... 1111 2.2.1 Load Capacity ........................................................................................................... 1111 2.2.2 Ice Growth ................................................................................................................ 1111 2.2.3 Ice Decay ................................................................................................................... 1313 2.2.4 Freshwater Ice Temperature Profiles ........................................................................ 1414 2.2.5 Convection/Mixing in Ice Covered Lakes ................................................................ 1616 2.3 Ice Measuring Methods ................................................................................................... 1717 2.3.1 Mechanical................................................................................................................ 1717 2.3.2 Sonar ......................................................................................................................... 1919 2.3.3 Temperature .............................................................................................................. 2121 2.3.4 Research Summary ................................................................................................... 2323 3.0 Design Specifications.......................................................................................................... 2525 4.0 Preliminary Design Components ........................................................................................ 2626 4.1 NTC Thermistor .............................................................................................................. 2626 4.1.1 Temperature Range................................................................................................... 2626 4.1.2 Accuracy ................................................................................................................... 2626 4.1.3 Stability ..................................................................................................................... 2727 4.1.4 Packaging.................................................................................................................. 2727 4.2 Microcontroller Board ..................................................................................................... 2828 4.2.1 Arduino ..................................................................................................................... 2828 4.3 Circuitry .......................................................................................................................... 3030 4.3.1 Wiring Diagram ........................................................................................................ 3030 ii 4.3.2 Thermistor Circuitry ................................................................................................. 3030 4.4 Software .......................................................................................................................... 3232 4.5 Power Supply .................................................................................................................. 3333 4.5.1 Battery ...................................................................................................................... 3333 4.5.2 Photovoltaic .............................................................................................................. 3333 4.6 Flotation .......................................................................................................................... 3535 4.6.1 Flotation Type........................................................................................................... 3535 4.7 Frame ............................................................................................................................... 3838 4.7.1 Design 1: B1318BO................................................................................................. 3838 4.7.2 Design 2: B1848BO................................................................................................. 3939 5.0 Proof of Concept ................................................................................................................. 4141 5.1 Thermistor Chain............................................................................................................. 4343 5.2 Lake Simulation .............................................................................................................. 4444 5.3 Arduino Code .................................................................................................................. 4444 6.0 Results & Analysis .............................................................................................................. 4646 7.0 Conclusion & Future Recommendations ............................................................................ 5050 Appendix A: NTC Thermistor Probe ....................................................................................... 5252 Appendix B: Arduino Code ..................................................................................................... 5353 Appendix C: Ice Formation Stage............................................................................................ 5757 Data Set 8: ............................................................................................................................. 5757 Data Set 9: ............................................................................................................................. 5757 Data Set 10: ........................................................................................................................... 5858 Data Set 11: ........................................................................................................................... 5858 Data Set 12: ........................................................................................................................... 5959 Data Set 13: ........................................................................................................................... 5959 Data Set 14: ........................................................................................................................... 6060 Data Set 15: ........................................................................................................................... 6060 Data Set 16: ..........................................................................................................................
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