PowerPoint PresentationTeam MembersProblem StatementProject BreakdownDesign ConstraintsDesign ApproachPrototypeDesign Block DiagramMicrophone and AmplifierPhase Lock Loop SimulationBandpass Filter Using PLLPIC Logic Flow ChartReason For Using PIC 16C505Activation Time ConstraintsEfficiency TestResponse TestConstraintsProduction Cost per UnitSimilar ProductsFuture ModificationsSummaryAcknowledgementsQuestions?ReferencesSlide 2511Key Chain Key Chain LocatorLocatorECE 4512-02ECE 4512-0222Team MembersTeam MembersTeam Leader: Jared SealTeam Leader: Jared SealSteve CiaravinoSteve CiaravinoMichael SuttlarMichael SuttlarAlan LandrithAlan LandrithAdvisor:Advisor: Raymond WintonRaymond Winton33Problem StatementProblem StatementProblem: Searching for a lost set Problem: Searching for a lost set of keys can be very time of keys can be very time consuming and annoying. consuming and annoying. Solution: A small portable device Solution: A small portable device that will respond to a two-tone that will respond to a two-tone whistle sequence that can be whistle sequence that can be attached to a key chain.attached to a key chain.44ResearchDocumentation Website PLLPICSpice TestingMSProjectJared X X X X X X XSteve X X X X XMike X X X X Alan X X X XProject BreakdownProject Breakdown55Design Constraints Design Constraints Distance: The device will respond Distance: The device will respond within a 20 ft. radius.within a 20 ft. radius.Activation: The device will respond to Activation: The device will respond to a two-tone whistle sequence within a 3 a two-tone whistle sequence within a 3 second interval.second interval.Filter Constraint: The filter will have a Filter Constraint: The filter will have a bandwidth of less than 500Hz. bandwidth of less than 500Hz.66Design ApproachDesign ApproachA Phase Locked Loop (PLL) is used as a A Phase Locked Loop (PLL) is used as a highly selective bandpass filter to reject highly selective bandpass filter to reject unwanted frequencies in the input to the unwanted frequencies in the input to the system.system.A comparator is used with the PLL for A comparator is used with the PLL for inputs to the PIC.inputs to the PIC.PIC programming was used to minimize PIC programming was used to minimize false activations.false activations.77PrototypePrototype88Design Block DiagramDesign Block DiagramPLL (high) PLL (low)ComparatorPICBuzzerAmplifierMicrophone99Microphone and Microphone and Amplifier Amplifier Microphone provides input to the PLL CircuitsInverting ConfigurationTheoretical Gain =-R2/R1Gain = -10Meg/220 Gain = -4545.5Measured Gain ~ -5001010Phase Lock Loop Phase Lock Loop SimulationSimulationError Voltage = VE = V(input) – V(reference) The error voltage to the VCO increases until the input signal and the reference signal match. The VCO produces a DC output voltage indicative of the input signal. The polarity of the error voltage dictates whether the VCO output increases or decreases.1111Bandpass Filter Using Bandpass Filter Using PLLPLLTone OneDelta lock frequency = 300HzDelta capture frequency= 100HzCenter frequency = 830HzTone TwoDelta lock frequency= 300HzDelta capture frequency= 100HzCenter frequency = 2000Hz1212PIC Logic Flow ChartPIC Logic Flow ChartWaiting for Tone 1Waiting for Tone 2Is durationof Tone 1> 0.25sec?Is Tone 1 Detected?Is Tone 2Detected?Is 3-sec Timerexpired?BuzzerYesNoNoYesYesNo YesNo1313Reason For Using PIC Reason For Using PIC 16C50516C505•Allows implementation of a reset function in the system that only produces a response from two inputs within this time interval. •Has capability to connect with external device to improve response sound selection•Small instruction set facilitates easy programming and faster development time.•Low Power Consumption1414Activation Time Activation Time ConstraintsConstraintsTimer DelayCalculatedCalculated–3.00 seconds 3.00 seconds SimulationSimulation–2.81 seconds2.81 secondsLength of First toneLength of First toneCalculatedCalculated–0.25 seconds 0.25 seconds SimulationSimulation–0.24 seconds0.24 secondsCalculation:20us instruction cycle * 256 instructions * 49times = 0.251 secondsTimer increment every 256 instructions*Simulation with Mplab1515Efficiency Test Efficiency Test Distance Test: Distance Test: –Room AcousticsRoom AcousticsMaximum Ambient Maximum Ambient Room Noise Level: Room Noise Level: -35.14dB (Ref 0)-35.14dB (Ref 0)Maximum Signal Maximum Signal Level: -45.14dB Level: -45.14dB (Ref 0)(Ref 0)**Test were conducted in senior Test were conducted in senior design room and crowded design room and crowded electronics lab.electronics lab.* * Sound levels recorded by 256-pt FFT in Sound levels recorded by 256-pt FFT in Cool Edit Pro at a distance 10ft from the Cool Edit Pro at a distance 10ft from the tone generator (whistle simulator).tone generator (whistle simulator).ReliabitlityversusTimeDelayofPic0%20%40%60%80%100%120%2 4 6 8 10 12 14 16 18 20Distance(ft)MeanPercentEfficiencyTime delay of 0.5secondsTime delay of 0.25seconds1616Response Test Response Test Distance Test:Distance Test:-Performed in Micro Lab with Performed in Micro Lab with dBSPL meterdBSPL meter- 3 buzzers used: 3 buzzers used: 2.7kHz, 3.3kHz, 4kHz2.7kHz, 3.3kHz, 4kHz-3 angles: 03 angles: 0°° , 90 , 90 °°, and 180 , and 180 °° relative to buzzerrelative to buzzer-All tests were performed All tests were performed twicetwice-Performed with and without Performed with and without obstructionsobstructions-Graph shows mean value of Graph shows mean value of testingtestingSoundIntensityVersusDistance0.0020.0040.0060.0080.00100.002 4 6 8 10 12 14 16 18 20Distance(ft)MeandBSPL4k Buzzer2.7k Buzzer3.3k Buzzer1717ConstraintsConstraintsConstraintConstraintResultResultDistanceDistanceRespond up Respond up to a to a distance of distance of 20 ft. 20 ft. The device was at The device was at least 90% accurate least 90% accurate up to 10 feet, and up to 10 feet, and responded to two-responded to two-tone signals at 20 tone signals at 20 feet.feet.FilterFilterBandwidth Bandwidth of less than of less than 500Hz500HzLock range of Lock range of approximately 300 approximately 300 Hz, capture range of Hz, capture range of approximately 100 approximately 100 HzHzActivatioActivationnRespond Respond within a 3 within a 3 second second intervalintervalPic simulation: Pic
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