Safety Protocol Systems

Driverless System Status Indicator (DSSI)

Driverless System Status Indicator consists of blue and yellow indicators required by FSAE DT.1.2, visually indicating the vehicle’s current driverless state. 24a is equipped with three pairs of commercially available 12VDC LED strips to satisfy this requirement, with two pairs on each side of one pair on the rear element of the rear wing. The DSSI logic are as follows:

  • DS Off: Off

  • DS Ready: Yellow continuous (Vehicle in HV Enable, Ready-to-Drive; all safety checks met, ready to initiate selected driverless mission.)

  • DS Driving: Yellow flashing (Vehicle currently initiating the selected driverless mission.)

  • DS Finished: Blue continuous (Vehicle has completed the selected driverless mission and is at a standstill.)

  • DS Emergency: Blue flashing (Vehicle has encountered an emergency, either through the RES or upon entering its own error states. EBS actuates as the shutdown circuit opens.)

FSAE DT.1.3 requires the Driverless Alert Sound to be triggered when the vehicle is in the state of DS Emergency. 24a utilizes the existing Ready-to-Drive buzzer to fulfill this requirement. During the driverless electrical technical inspection, teams are required to showcase an “inspection” mission to verify the correct functionality of the DSSI, the Driverless Alert Sound, as well as the correct behavior of the EBS at various vehicle states.

Driverless System Master Switch (DSMS)

Driverless System Master Switch is an additional master switch by the existing GLVMS and TSMS, required for driverless vehicles. The DSMS is in series with post-GLVMS, serves as an input to Driverless System relay and Emergency Brake System relay logic, and directly supplies power to the Remote Stop relay, allowing the switching between manual and driverless modes.

Remote Emergency Stop (RES) and Relay

To ensure FSAE DT3.3, 24a implemented a FSG-certified RES system, Gross Funk T53 transmitter and GF2000i R98 receiver. The remote stop relay of the RES is directly hard-wired in series with 24a’s safety circuit. The RES has two roles:

  • Go Button: Transmit “go” signals to initiate the selected driverless mission

  • Stop Button: Bring 24a to a safe condition remotely by opening the safety circuit, disabling the tractive system, and triggering the EBS relay for the emergency stop.

An additional normally-closed relay powered off the DSMS ensures the bypass of the remote stop relay of the RES, allowing the manual operation of the vehicle when DSMS is in off state.

_images/res.png