o Portable low-cost aerial drone that can be used for reconnaissance o Relay real-time video and data, like location, heading, battery life o Take high-resolution pictures of the ground in flight o Store photos and some flight data in non- volatile memory, á la “blackbox” system. o Control drone manually via a control unit
Three main functional blocks: Power: LTC1174 (3.3V switching regulator) and application circuit, FSAL200 (analog multiplexer), DS2438 (battery monitor) and application circuit, opto-isolator Microcontroller: AT32UC3C0256 Sensors/Peripherals: XBee, MPU-6050 (IMU), BMP085 (altimeter), HMC6352 (compass), SD card
LTC1174: relatively high power and complex compared to other components on our board, high criticality failures associated with failure of this device AT32UC3C0256: high complexity, relatively high criticality failures FSAL200: low complexity but high criticality failures
Model: λ P = (C 1 π T + C 2 π E )π Q π L λ P = Total failure rate: 1.86x10 -7 per hour
Model: λ P = λ BD π MFG π T π CD + λ BP π E π Q π PT + λ EOS λ P = Total failure rate: 4.619x10 -7 per hour
Model: λ P = 20λ B π T π Q π E λ P = Total failure rate: 6x10 -6 per hour
Failure No.Failure ModePossible CausesFailure EffectsMethod of DetectionCriticality P-1 LTC1174 Output = 0V External short, decoupling capacitor short Plane stops flyingObservationHigh P-2 LTC1174 Output > 3.3V Failure of U1 or sensorsControl of plane transfers to COTS controller Observation (controls through computer stop working) Medium P-3 LTC1174 Output out of tolerance Failure of L2, clamping diode, or decoupling capacitors Possible loss of control of plane ObservationHigh P-4 Opto-isolator output 0VBurnout, excess current draw from video system (short) Loss of video streamingSoftware checklow P-5 FSAL200 No Output Passed too much current, transistor aging Loss of control of planeObservationHigh P-6 FSAL200 Stuck at microcontroller output GPIO failure, internal buffer failure, transistor aging Dormant control failurePre-flight testLow P-7 FSAL200 Stuck at COTS controller output GPIO failure, internal buffer failure, transistor aging Loss of control through micro ObservationLow P-8 DS2438 Incorrect data SPI failureInvalid battery dataObservation (plane may be unable to climb when it apparently has enough power) Medium
Failure No.Failure ModePossible CausesFailure EffectsMethod of DetectionCriticality M-1PWM failureSoftware error, mechanical vibration/shock, power out of tolerance, transistor aging Plane stops flyingObservationHigh M-2UART failureSoftware error, mechanical vibration/shock, power out of tolerance, transistor aging Transfer of control to COTS controller, possibly only loss of GPS data Observation (controls through computer stop working) Medium M-3SPI failureSoftware error, mechanical vibration/shock, power out of tolerance, transistor aging Loss of data storing capability, loss of compass data ObservationLow M-4I2C failureSoftware error, mechanical vibration/shock, power out of tolerance, transistor aging Loss of motion sensing ability Software checkLow M-5GPIO failureSoftware error, mechanical vibration/shock, power out of tolerance, transistor aging Loss of control of planeObservationHigh
Failure No.Failure ModePossible CausesFailure EffectsMethod of DetectionCriticality S-1XBee Loss of communication UART failureTransfer of control to COTS controller ObservationMedium S-2MPU-6050 IMU incorrect data I2C failureLoss of motion dataSoftware checkLow S-3SD card not storing dataSPI failureLoss of “Black Box”Observation after flight, possible software check Low S-4Altimeter incorrect dataSPI failureLoss of altitude sensing capability Software checkLow S-5Compass incorrect dataI2C failureLoss of headingSoftware checkLow S-6GPS incorrect dataUART failureLoss of location dataSoftware checkLow
Relatively low reliability Even if this product were brought to market, production volumes and amount of use would be very low Intended for use in relatively remote areas Software will be able to monitor for some low-criticality failures
Questions?