A Two-Input PolygraphArchana VenkataramanChristopher BuenrostroIsaac RosmarinOutline Introduction Design Overview The Physiological Sensors The Digital Decision-Making Unit (DDMU) The Output Display ConclusionIntroduction The polygraph detects stress-related physiological responses commonly linked with deception Modern-day polygraphs rely on 4 major variables: The Foundation of a lie-detector examination is in its structure Environmental Setting Experience and Conduct of Examinator Questions: Control, Irrelevant, and Relevant Decisions are based on the assumption that an innocent subject will react more strongly to the control questions and a guilty subject will react more strongly to the relevant questionsIntroduction The project uses 2 inputs to make decision–heart rate and skin conductivity Heart speeds up during times of emotional stress Perspire during times of emotional stress –increases conductivity Project divided into three sections The Physiological Sensors The Digital Decision-Making Unit The Output DisplayInput DevicesInputs DDMU VideoData Acquisition Flow DiagramHeart Rate MonitorProbe PatchesAttached to Test SubjectAnalog-to-Digital ConverterSkin Conductivity MonitorProbe PatchesAttached to Test SubjectAnalog-to-Digital ConverterDesignated Lab Kit RAM Refresh BlockInput DevicesInputs DDMU VideoData Acquisition Flow DiagramHeart Rate MonitorProbe PatchesAttached to Test SubjectAnalog-to-Digital ConverterSkin Conductivity MonitorProbe PatchesAttached to Test SubjectAnalog-to-Digital ConverterDesignated Lab Kit RAM Refresh BlockInput DevicesInputs DDMU VideoData Acquisition Flow DiagramHeart Rate MonitorProbe PatchesAttached to Test SubjectAnalog-to-Digital ConverterSkin Conductivity MonitorProbe PatchesAttached to Test SubjectAnalog-to-Digital ConverterDesignated Lab Kit RAM Refresh BlockInput DevicesInputs DDMU VideoData Acquisition Flow DiagramHeart Rate MonitorProbe PatchesAttached to Test SubjectAnalog-to-Digital ConverterSkin Conductivity MonitorProbe PatchesAttached to Test SubjectAnalog-to-Digital ConverterDesignated Lab Kit RAM Refresh BlockInput DevicesInputs DDMU VideoData Acquisition Flow DiagramHeart Rate MonitorProbe PatchesAttached to Test SubjectDesignated Lab Kit RAM Refresh BlockAnalog-to-Digital ConverterSkin Conductivity MonitorProbe PatchesAttached to Test SubjectAnalog-to-Digital ConverterInput DevicesInputs DDMU VideoData Acquisition Flow DiagramHeart Rate MonitorProbe PatchesAttached to Test SubjectDesignated Lab Kit RAM Refresh BlockAnalog-to-Digital ConverterSkin Conductivity MonitorProbe PatchesAttached to Test SubjectAnalog-to-Digital ConverterElectrocardiogram Heart Monitor*Images from http://ramseyelectronics.comInputs DDMU VideoRamsey Electronics ECG1CSkin Conductivity Monitor*Images from http://vismod.media.mit.edu/tech-reports/TR-542.pdfwith credit to Rosalind W. Picard and Jocelyn ScheirerInputs DDMU VideoThe GalvactivatorThe Digital Decision-Making UnitDesign Overview User Interface Decision-Making Portion Based on Polygraph Data Additional Functions Obtain Data Stored Externally in RAM Prepare/Send Data to Display UnitData to Be Displayed on Screen MemoryModuleDisplayDriverDecision-Making AlgorithmUser CommandsCaptureUser InputsData RegisterScreen Capture CommandsTo Memory Interface ModuleTo Memory Interface ModuleInputs DDMU VideoCapturing User Commands Module registers all user inputs and passes them to appropriate module User Commands: Type of Question Analyze Results Display Data Store Data Screen CaptureData to Be Displayed on Screen MemoryModuleDisplayDriverDecision-Making AlgorithmUser CommandsCaptureUser InputsData RegisterTo Memory Interface ModuleScreen Capture CommandsTo Memory Interface ModuleInputs DDMU VideoDecision-Making Algorithms Main Module of the DDMU –Analyzes sensor data and outputs binary “TRUTH/LIE”decision Digital Pre-Processing on data to remove extraneous, environmental factors Average incoming data Highpass Filter Implement one or more of following algorithms: Compare statistics of time signal Convert to frequency domain and compare Hypothesis TestingData to Be Displayed on Screen MemoryModuleDisplayDriverDecision-Making AlgorithmUser CommandsCaptureUser InputsData RegisterTo Memory Interface ModuleScreen Capture CommandsTo Memory Interface ModuleInputs DDMU VideoThe Memory Module and Data Register The Memory Module signals Memory Interface to Read from and Write to RAM by asserting a “request” signal Data Register holds critical values for the Decision-Making Algorithm: Time sequences to be compared Computed StatisticsData to Be Displayed on Screen MemoryModuleDisplayDriverDecision-Making AlgorithmUser CommandsCaptureUser InputsData RegisterTo Memory Interface ModuleScreen Capture CommandsTo Memory Interface ModuleInputs DDMU VideoDisplay Driver Gathers data to be sent to Display Unit Sensor Data Decision (T/F) Screen Capture Command Data to Be Displayed on Screen MemoryModuleDisplayDriverDecision-Making AlgorithmUser CommandsCaptureUser InputsData RegisterTo Memory Interface ModuleScreen Capture CommandsTo Memory Interface ModuleInputs DDMU VideoVideo DisplayJob of the Video Display Take in data and convert to a visually appealing format Display data Save previous data for referenceInputs DDMU Video On computer monitor Like PS3/Lab 4 Higher ResolutionInputs DDMU VideoVideo Output Register data on vsync refresh Convert data into an eye-pleasing formatInputs DDMU VideoData Inputs Compresses data to save Displays previous data Interacts with onboard RAM Changes based on user inputInputs DDMU VideoVideo StorageConclusion Design is modular Project is good extension to material presented in class Polygraph is an interesting real-world
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