Design Of Multi-function Stalk Switch For Passenger Car

Multi-Function Stalk Switch is an important control in the passenger car.It is a combination of switches to control the lighting system,the wiper systerm.It also supports the switches on the steering wheel,dirver airbag,horn,etc.Along with the development of the vehicle technology.Multi-Function Stalk Switch is changing to be electronic,even smart design.Based on the design of Multi-Function Stalk Switch used on car from F motor company,the design specification and requirements are summarized.The implementation solution of Multi-Function Stalk Switch is split into 3 parts,mechanical design,hardware design,software design.Firstly,the paper summarizes the specification and requirements applied to Multi-Function Stalk Switch.It includes regulation,function,environmental performance,electrical magnetic compatibility,HMI.China,EU,US get its own regulation requirements,covering safety,symbols.Function requirement is deployed from the vehicle level.Environmental performance basically makes sure the switch can withstand the extreme temperation,humidity,vibration,dust,salt contditions that could happen on the vehicle.The stalk switch is expected to be human friendly design,so the driver can easily operate the stalks.Secondly,the implementation solution of Multi-Function Stalk Switch is summarized based on the design from F motor company.Mechanical deisgn includes turn signal stalk,wiper stalk,clockspring,carrier.The force curve design,turn stalk auto canceling system design,contact system design are the key factors.Hardware design is based on the microcontroller.The stalk switch will need to sample,filter the input and send the output to the other modules through CAN/LIN bus.It is the termination node of CAN bus and the master of LIN bus for wiper control.The paper indicates the schematic of microcontroller,DC-DC converter,CAN/LIN interface circuits and the interface with the switches.Software design follow the concept of platform and moduler design.The paper will demonstrate the network operation systeam,diagnostic,bootloader and application software.After that,the testing method is introduced with the support of several results.At last,the design challenges are listed for Muti-Function Stalk Switch.The future design concept is shared.