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Stream Depth Gauge. Team: SDMAY 12-23. Team Members John Henderson Curt LaBarge Greg Pearson Yixin Qiao. Client/Advisor Steve Holland (ISU Canoe and Kayak Club). Problem Statement. Iowa flow levels change often Current gauging strategies are inadequate High Maintenance
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Stream Depth Gauge Team: SDMAY 12-23 Team Members John Henderson Curt LaBarge Greg Pearson Yixin Qiao Client/Advisor Steve Holland (ISU Canoe and Kayak Club)
Problem Statement Iowa flow levels change often • Current gauging strategies are inadequate • High Maintenance • At threat of cancelation • Cover a limited amount of streams and rivers • Canoers and Kayakers need easy access to flow data to accurately plan trips • Some waterways are currently not monitored Photo Credits: ISU Canoe and Kayak Club SDMAY12-23
Solution Design and build a low-cost stream depth gauge The gauge should be: • Affordable • Self contained • Robust in the environment • Capable of operating for long period of time • Capable of transmitting measurements wirelessly SDMAY12-23
Market Survey Current gauging done mostly by United States Geological Survey These gauges are expensive • $5,000/yr to maintain Complex Design • Stilling basin • Two story structure • Under ground pipes • Electronic recorder Typical USGS Gauge Design Photo Credit: USGS http://ga.water.usgs.gov/edu/streamflow1.html SDMAY12-23
Functional Specifications • Total Price of Materials < $500 • Measurement Accuracy: 1inch • Operating Temp: -5°C to 70°C • Survivable Temp: -40°C to 70°C • Daily data transmission • Power save during winter SDMAY12-23
Non Functional Specifications • Low maintenance cost • Long battery life • Minimum: 1 yr • Rugged design • Weatherproof • Low power consumption SDMAY12-23
Schedule • Semester 1 • Conducted research • Identified design requirements • Rough schematic design • Purchased major components • Semester 2 • Purchased new parts as needed • Programmed micro-controller • Implemented cell module • Comprehensive testing of equipment • PCB design SDMAY12-23
Concept Sketch SDMAY12-23
Under Water HousingConcept and Design • Water level is proportional to air pressure inside cylinder • As water depth over cylinder increases, so does air pressure • Housing and tubing buried under a sand bank for added protection against floating debris AIR Tube to Pressure Sensor SDMAY12-23
System Design • Atmel ATMega128 • Telit GM-862 • Freescale MPX2050 SDMAY12-23
Power Design • Voltage Regulators • 5 W Solar Panel • Charging Circuit • Two 6 Volt Batteries SDMAY12-23
Software Design • State Machine SDMAY12-23
Block Diagram SDMAY12-23
Hardware Changes • Level Shifters • MC14504BDR2GOSCT-ND • Voltage Regulators • LT1764AEQ#PBF (Cell Modem) • TPS7A1650DGNR (Microcontroller) • Instrumentation Amplifier SDMAY12-23
Software Changes • Watchdog timer • Debugging • UART USB • LEDs • Buzzer • AT Commands • Consolidated States SDMAY12-23
LED Helper • 4 LEDs on the CEREBOT II board • To display the values by binary number • Indicates the number of digits of the variable • Display from the least significant digit to most significant digit • Helped in testing temperature sensor and pressure sensor SDMAY12-23
Sleep Testing • Used for power saving • 6 sleep modes • Idle, ADC Noise Reduction, Power-down, Power-save, Standby, Extended Standby • Atmega128 doesn’t support Watchdog interrupt • Idle mode with Timer0 SDMAY12-23
Temperature Sensor Testing • Find the output of 32ᵒF Cutting point • When lower than 32ᵒF, go to sleep • When higher than 32ᵒF, measure the pressure • Temperature chamber was used to find cut-off point. SDMAY12-23
Pressure Sensor Testing • Instrumental amplifier to obtain the difference of the two outputs • With gain of 4000 (for testing) • Max output of the amplifier is 5V • Measures from 2 to 15 inches • Accurate to 1 inch • Tested with a 2-liter bottle with 9-inch hight SDMAY12-23
Testing the Cell Modem • Cell Modem Tests happened in two phases • Testing AT commands with a computer via USB. • Testing UART communication between microcontroller and Cell Modem
AT Communication • Cell Modem is controlled via different AT Commands • First Testing stage tested the usage of these AT commands: • AT • AT+CREG=? • AT+CMGF=1 • AT+CMGS=“<phonenumber>” • AT#SHDN
UART Communication • Second Phase of Testing involved UART Communication between the • Cell Modem – 3V logic • Microcontroller – 5V logic • Voltage level shifter SDMAY12-23
UART Communication • We used USB to Serial device that could read UART communication to test. • Showed us transmitting signal to make sure signal was correct SDMAY12-23
Full Software Testing • For the full Software Testing, we breadboarded all components together. • System could run through each state in the State machine. • Each component worked together with everything assembled SDMAY12-23
Conclusions • Our device performs its intended purpose: To measures and transmit an accurate water height • The device could be easily expanded upon: Database to store river height information SDMAY12-23
Lessons Learned • We learned that communication is key to getting things done properly. • The project gave us a more realistic view of what problem solving is like • Having the right tools make getting the job done exponentially faster SDMAY12-23
Questions ? Brief Summary • Stream depth gauge • Components • Pressure sensor • Microcontroller • Cell Module • Power Circuitry ? ? ? ? ? ? SDMAY12-23