PreCise PF3400 - Safety Circuits for PF3400 3 Kg Payload

PreciseFlex_Robot
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Appendix D2: Safety Circuits for PF3400 3kg Payload
14‐Jun‐17
SafetyCircuit
StartupTest
1
Redundant ContinuousTe st DiagnosticCoverage MTTFdl, Years
PowerOffOnFailure
PL CategorySafety
Notes(PF3400thasre du ndantEstopand48Vpowersupply enable)
Estop Yes Yes No 9 9% 100 Yes d 3 StartuptestforcesEstop,checks48Vpowerdisable, zeroampcurrent
DualEstopcircuitsturnsoff ampenableandPWM
DualEstopcircuitsturnSoff48Vpower
Stoppingrobotwithhandturnsoffampenable,PWMand48V
EncoderFeedback Yes No Yes 90% 58 Yes d 3 Startuptestchecksencoder
communication,preventsmtrpoweriffault
Serial updateat8Khzwchecksum,commcheck,accelcheck
CounterembeddedinpositionwordtoconfirmCPUreadfromFPGA
CPUMonitor Yes Yes Yes 99% 100 Yes d 3 StartuptestforcesCPUWDlow,checks48Vpowerdisabled
Independe ntdualwatchdogtimersturnoffampenable,PWMand48V
Processoronsafetyboard
monitorsmain CPU.Disables48Viffailure.
PositionEnvelopeError Yes Yes Yes 90% 57 Yes d 3 Startuptestchecksencodercommunication,preventsmtrpoweriffault
Serial updateat8Khzwchecksum,commcheck,accelcheck
SWwatchdoginservoloopturnsoff ampenable,PWMand48V
CounterembeddedinpositionwordtoconfirmCPUreadfromFPGA
Power
ampFault Yes Yes Yes 90% 100 Yes d 3 Startuptestconfirmszerocurrentwhen48Venabled
Excesscurrenttoground orphasetophasetriggersshutdownin10usec
SaturatedPIDcurrentcommandtriggersshutdownin.050sec
Shortedtransistorjustlocksupbrushless motor
CollabForceLimit Yes Yes Yes 90% SW Yes d 3 Tests2,3,4abovetestHW.Motordrivenagainstbraketotest
SWcurrentlimit.
Positionenvelopeerrortriggersfault,turnsoffpoweratampand48V
Currentsaturationtriggersseparatefault,turnsoff poweratampand48V
Moni torfunctionwithWDturnsoffpoweratampand48V
Moni torandCPUWDtestedatstartupturningoff48V
AssymetriccurrentlimitslimitZ
forceevenwi thgravityload
Veloci tyRestrict Yes Yes Yes 99% 93 Yes d 3 Startuptest,setsflagtotriggerthiserror,thenresets
Checksvel ocitylimitinFPGAinadditiontocheckinCPUservosoftware
1.Cat2andCat3requirestartuptestbeforeenablingmotorpower
PF3400