1. Adaptive Cruise Control Group 2 Presenters:Lydia Eatmon Ben Deneweth Toby Tripp Craig Vasel

2. Unique Feature of System Adjustable safe distance interval Components of adjustable safe distance interval –User interface (at this point unspecified)

3. What Does Feature Support? Functionality of unique feature –Allows driver to adjust the safe distance –Does not allow driver to make the safe distance less than 2 seconds Sample scenario description –Useful for slippery road conditions

4. Key Model Controller state diagram Why important –Where all the work of the ACC is done –Makes all the decisions of the system

5. Controller Model Idle No Cars Ahead Current_speed > 25mph Car Ahead Contact Lost Lead Vehicle Is Too Slow Lead Vehicle Is Too Close Safe Now Contact Gone

6. Key Model Class diagram of entire system Why important –Clarifies how different segments work at the same time –Shows main aspects of system

7. Class Model Adaptive Cruise Control Sensor Speed Radar Cruise Control Actuator Brake Speed Cruise Control Engine Speed User Interface Active Indicator Warning Indicator Safe Interval Adjustment Controller Contact

8. Critical Properties Representative list of critical properties –Collision avoidance –Maintains safe distance –Resumes driver control –Imminent collision warning (Safety) (Liveness) (Safety)

9. Promela and XSpin Analysis –Modeled entire system, separating states with labels –Tested with random sensor feedback –Tested specific event sequences Results –Identified potential deadlock –Verified model behavior Reachability Safety/Liveness Assertions /* "Idle" State */ end_ctrl_idle: ctrl_idle: do :: get_speed!signal; ret_speed?current_speed; if :: ( current_speed goto ctrl_idle; :: ( current_speed > 25 ) -> goto ctrl_no_cars; fi; od; init{ host_speed = 65; target_speed = 45; target_distance = 350; cruise = OFF; radar = CONTACT; radar = NOCONTACT; cruise = ON; host_speed = 85; target_speed = 55; target_distance = 280; radar = CONTACT; } /* speed sensor model */ active proctype speed_sensor() { end_speed_sensor: do :: get_speed?_; ret_speed!10; :: get_speed?_; ret_speed!25; … :: get_speed?_; ret_speed!95; od; } [] ( sentNoContact -> <> (resumeCruise || resumeEngine)) #define sentNoContactradar_sensor[1]@sent_no_contact #define resumeCruisecruise_actuator[1]@resume_cruise #define resumeEngineengine_actuator[1]@resume_engine