Aiming at the problem that while driving in expressway tunnel

driver can not judge the condensed ice condition of the road

which will affect the driving safety

an intelligent lane indicator is proposed. It can not only guide the basic functions of the vehicle traveling in the specified direction in the tunnel

but also can flexibly change speed limit sign according to the tunnel condition. In addition

the tunnel hole environmental parameters can be collected

the road ice condensing risk warning model is used to calculate the pavement icing probability

and the speed limit sign is changed to alert the driver to improve driving safety. The intelligent lane indicator uses STM32 series chip as the main controller

with infrared non-contact temperature sensing module

humidity sensor module and light emitting diode（ LED） display module. After the hardware connection and the icing risk model are programmed and debugged

the lane indicator realizes the probability prediction of the icing risk according to the tunnel environment data

and changes the speed limit flag to alert the driver.