5/24/2002 CDIO3 Class Project 68SubsystemRequirementsz Determine separation distancez Goal: sense to one-tenth the control tolerancez Determine relative attitude (direction) ofvehicle to an angular tolerance dependenton angular controllabilityz Goal: sense to one-tenth the control tolerancez Full field of view : 360 degrees in twodimensionsz Sensing presence of other vehicles to adistance compatible with test facilitiesIntroductionSubsystems•Actuation•Formation Control•Control•Metrology•Requirements•Trades•Design•Issues•BudgetEstimates•Electronics•Structure/PowerOperationsImplementationConclusion5/24/2002 CDIO3 Class Project 69TradesSonic and IR based systemz Similar to SPHERES metrologyz Expected improvement inperformance due to 2D operationz New technology should eliminatesome accuracy of the errorsencountered by SPHERESz Low refresh rate will require theuse of gyros and accelerometersIntroductionSubsystems•Actuation•Formation Control•Control•Metrology•Requirements•Trades•Design•Issues•BudgetEstimates•Electronics•Structure/PowerOperationsImplementationConclusion5/24/2002 CDIO3 Class Project 70DesignACBαBβAsABt1t3t2IntroductionSubsystems•Actuation•Formation Control•Control•Metrology•Requirements•Trades•Design•Issues•BudgetEstimates•Electronics•Structure/PowerOperationsImplementationConclusion5/24/2002 CDIO3 Class Project 71Design1 ultrasonic omni-directionaltransmitter (Mimio)3 ultrasonic omni-directionalreceivers (cones)3 IR receivers & 2 transmitters1rategyro1 2-axis accelerometerIntroductionSubsystems•Actuation•Formation Control•Control•Metrology•Requirements•Trades•Design•Issues•BudgetEstimates•Electronics•Structure/PowerOperationsImplementationConclusion5/24/2002 CDIO3 Class Project 72DesignIntroductionSubsystems•Actuation•Formation Control•Control•Metrology•Requirements•Trades•Design•Issues•BudgetEstimates•Electronics•Structure/PowerOperationsImplementationConclusion5/24/2002 CDIO3 Class Project 73DesignSystem relies only on distancereadingsUses data from all three sensorsCalculates relative attitude anddistance directly to center ofvehicleIntroductionSubsystems•Actuation•Formation Control•Control•Metrology•Requirements•Trades•Design•Issues•BudgetEstimates•Electronics•Structure/PowerOperationsImplementationConclusion5/24/2002 CDIO3 Class Project 74Design(x + x1)2+ (y + y1)2= d12(x + x2)2+ (y + y2)2= d22(x + x3)2+ (y + y3)2= d32YXd1•Origin at center of vehicle•xiand yiare position of thesensorsIntroductionSubsystems•Actuation•Formation Control•Control•Metrology•Requirements•Trades•Design•Issues•BudgetEstimates•Electronics•Structure/PowerOperationsImplementationConclusion5/24/2002 CDIO3 Class Project 75DesignIntroductionSubsystems•Actuation•Formation Control•Control•Metrology•Requirements•Trades•Design•Issues•BudgetEstimates•Electronics•Structure/PowerOperationsImplementationConclusion5/24/2002 CDIO3 Class Project 76IssuesOmni-directional sonic sensorsz Hand made cones added to currentsensorsEffect of magnetic forcesRange and accuracyRefresh ratez Sound signal leaving the testing areaz Rate gyros and accelerometersIntroductionSubsystems•Actuation•Formation Control•Control•Metrology•Requirements•Trades•Design•Issues•BudgetEstimates•Electronics•Structure/PowerOperationsImplementationConclusion5/24/2002 CDIO3 Class Project 77Budget Estimates1.090.202500Total (per vehicle)3.270.607500Total (system)0.180.051200Accelerometers0.360.061200Gyros0.250.0430IR (2+3)0.30.0570Sonic (1+3)Power(W)Mass(kg)Cost($)PartIntroductionSubsystems•Actuation•Formation Control•Control•Metrology•Requirements•Trades•Design•Issues•BudgetEstimates•Electronics•Structure/PowerOperationsImplementationConclusion5/24/2002 CDIO3 Class Project 78CommunicationsJennifer UnderwoodComm. BoardComm. AntennaIntroductionSubsystems•Actuation•Formation Control•Electronics•Comm•Requirements•Trades•Design•Issues•BudgetEstimates•Avionics•Structure/PowerOperationsImplementationConclusion5/24/2002 CDIO3 Class Project 79Communications“The technology employed intransmitting messages”z Architecturez Hardwarez Softwarez InterfacingIntroductionSubsystems•Actuation•Formation Control•Electronics•Comm•Requirements•Trades•Design•Issues•BudgetEstimates•Avionics•Structure/PowerOperationsImplementationConclusion5/24/2002 CDIO3 Class Project 80SubsystemRequirementsSend information and instructions automaticallyfrom vehicle to vehiclez Control and metrology purposesSend information and instructions on commandfrom ground to vehiclez Begin preprogrammed testsz Emergency intervention proceduresSend flight health data to “ground” operatorHave no protruding antennae that might interferewith dynamicsIntroductionSubsystems•Actuation•Formation Control•Electronics•Comm•Requirements•Trades•Design•Issues•BudgetEstimates•Avionics•Structure/PowerOperationsImplementationConclusion5/24/2002 CDIO3 Class Project 81TradesHardwarez Processor board (chosen byavionics Æ TT8)z TransceiverArchitectureIntroductionSubsystems•Actuation•Formation Control•Electronics•Comm•Requirements•Trades•Design•Issues•BudgetEstimates•Avionics•Structure/PowerOperationsImplementationConclusion5/24/2002 CDIO3 Class Project 82Transceiver MetricsEM rejection (frequency)Bandwidth/data rateWeightEase of interfaceSizeCostPower consumptionRangeIntroductionSubsystems•Actuation•Formation Control•Electronics•Comm•Requirements•Trades•Design•Issues•BudgetEstimates•Avionics•Structure/PowerOperationsImplementationConclusion5/24/2002 CDIO3 Class Project 83Transceiver TradesRadio Frequency (RF) vs.. WirelessLANz Avg cost of LAN > avg cost of RFz LAN requires a base station ($$)z Size and weight of LAN > RFz LAN bandwidth, range > RFz Power drain of LAN < RFz Both have capacity to reject EM (highfrequencies) and are easily interfacedChoice: RFIntroductionSubsystems•Actuation•Formation Control•Electronics•Comm•Requirements•Trades•Design•Issues•BudgetEstimates•Avionics•Structure/PowerOperationsImplementationConclusion5/24/2002 CDIO3 Class Project 84RF TradesDR1012 avail from SPHERESfor prototypingCompany inEuropeAvailability115.2 kbps115.2-882 kbpsData rateShort-range wireless91m indoorsRangeRelatively EasyRelatively EasyEase of