tcsp8 reliability and safety analysis ece477 group 4 chris cadwallader craig pilcher andy sydelko...
TRANSCRIPT
TCSP8Rel iab i l i ty and Safe ty Analys i s
ECE477 GROUP 4
CHRIS CADWALLADERCRAIG PILCHERANDY SYDELKOMIKE WILLIAMS
Project Forget-Me-Not
Reliability and Safety Concerns
False negative – Child present, but not detected Could lead to physical harm or death
Unintended manipulation of host vehicle Undesired CAN trasmissions
Component failure due to excessive heat Overuse of the audio amplifier
Components Likely to Fail
Freescale 9S12DP256C– High complexity microcontroller
TAS5710 – Audio amplifier Mounted upright, no heatsink
LM5705 – Linear regulator Majority source of heat
Linx tranciever – Wireless module
Mitigation of Safety and Reliability Issues
Failure Mode Possible Causes Failure Effect Detection Method Criticality
Unintended transmissions on CAN bus
Software errors Commands sent to host vehicle accidentally
Observable Medium – user dissatisfaction
No communication between remove and base station
Failure of a linx module or one of the encoder/decoder chips
Unable to detect child presence or removal.
Observable High
Vcc short to ground
Failure of the linear regulator
Excessive heat and current. Possible source of fire.
Observation; heat and smoke likely.
High
Loss of communication on CAN bus
Failure of the high speed or single wire CAN tranceivers
Inability to issue commands to the host vehicle
Measureable: Absence of traffic on the CAN lines.
High
Mitigation of Safety and Reliability Issues
Proper de-rating of components to increase reliability
Additional measures or handshaking to prevent child side detection misses due to RF interference.
Conservative use of the audio amplifier
Determine a detection method for failure of the RF interface
Questions?