Have a Safe Flight: Bon Voyage!Making the “Smart Flight Vest”Controlling ThrottleMain Block DiagramMeasuring the Roll of the PlaneMeasuring the Pitch of the PlaneADXRS300 - Angular Rate SensorGetting an Angle from Angular RateInterfacing the ADXRS300Interfacing the ADXRS300Timing Operation DiagramData Read OperationForces Determined in Physics ModuleForces on an AirplaneForce equationsAircraft RotationsRotation produces VectorsDisplaying the State of the FlightVideo Display Block DiagramScreenshotDisplaying numbersAttitude IndicatorAttitude Indicator – AlgorithmHave a Safe Flight: Bon Voyage!z Mariela Buchin, Wonron Cho, Scott FisherMaking the “Smart Flight Vest”z Mount two angular rate sensors onto the upper body of the flight vestz Separate device will measure throttleControlling Throttlez Want functionality of being able to adjust and set throttlez Will mount a handle onto resistor arm to imitate a throttle leverMain Block DiagramMeasuring the Roll of the PlanePlease see http://www.grc.nasa.gov/WWW/K-12/airplane/roll.htmlMeasuring the Pitch of the PlanePlease see http://www.grc.nasa.gov/WWW/K-12/airplane/pitch.htmlADXRS300 - Angular Rate Sensorz Contains an internal Gyroscopez Output voltage proportional to the angular rate about the axis perpendicular to the surface of the chipz Range of rate: +/- 300 o/secz Zero movement: outputs 2.5 VGetting an Angle from Angular Ratez AngleRate = K * (ADCVoltage-ZeroVoltage)z K is some constant (Degs/sec/volt)z Angle = Angle + AngleRate*deltaTz May need calibration for ZeroVoltageInterfacing the ADXRS300z Will use an analog to digital converter AD7895AN-2z Output of the AD7895 is 12 bitsz Uses a reference potential of 2.5 volts z Serial OutputInterfacing the ADXRS300z Bandwidth of the ADXRS300: 400Hzz Minimum sampling rate for ADC is 800Hzz We’ll use 10 KHz sampling rateTiming Operation DiagramData Read Operationz AD7895 uses 16 clock cycles to output the digital data bits resulting from the conversionz It outputs 4 leading zeros, then the 12 bits of actual data, starting with the MSB(DB 11)Forces Determined in Physics Modulez Forces and Anglular Velocities determined in Minor FSMz Positions and Angles calculated in Physics FSMForces on an AirplanePlease see http://www.grc.nasa.gov/WWW/K-12/airplane/forces.htmlForce equationsz Thrust: F = maz Weight: F = mglift = CL x ( rV ) x S2drag = CD x ( 1 rV2) x A221Please see: http://www.grc.nasa.gov/WWW/K-12/WindTunnel/Activities/lift_formula1.GIFhttp://www.grc.nasa.gov/WWW/K-12/airplane/lifteq.htmlhttp://www.grc.nasa.gov/WWW/K-12/airplane/drageq.htmlAircraft RotationsPlease see http://www.grc.nasa.gov/WWW/K-12/airplane/rotations.htmlRotation produces VectorsPlease see http://www.grc.nasa.gov/WWW/K-12/airplane/turns.htmlDisplaying the State of the Flightz The pilot flying the plane stands in front of a monitor that displays the main features of an airplane console, including an attitude indicator and a display for altitude, ascent rate, and velocity.Video Display Block DiagramScreenshotDisplaying numbersz Approach 1- Instantiate rectangles to form numbers (similar to how MIT logo was made in the Pong game)z Approach 2- Create and store table of ASCII characters in memory and render characters when they are neededAttitude Indicatorz The Attitude Indicator Module takes in two angles (pitch and roll).z The roll of the airplane determines the slope of the white line (horizon) .z The area above is colored blue (sky).z The area below is colored brown (earth).z The pitch determines the position of the horizon.Attitude Indicator – Algorithm z The goal is to make the horizon shift and rotate in response to pitch and roll.z When airplane is flying “sideways,” a different equation is used to draw the line representing the
View Full Document
Unlocking...