Operations of a Shared Autonomous Vehicle Fleet for the Austin, Texas Market

33 The emergence of automated vehicles holds great promise for the future of transportation. While 34 it commercial sales of fully self-driving vehicles will not commence for several more years, once 35 this is possible, a new transportation mode for personal travel looks set to arrive. This new mode 36 is the shared autonomous (or fully-automated) vehicle (SAV), combining features of short-term 37 on-demand rentals with self-driving capabilities: in essence, a driverless taxi. 38 39 This investigation examines SAVs’ potential implications at a low level of market penetration 40 (1.3% of regional trips) by simulating a fleet of SAVs serving travelers in Austin, Texas’ 12-mile 41 by 24-mile regional core. The simulation uses a sample of trips from the region’s planning 42 model to generate demand across traffic analysis zones and a 32,272-link network. Trips call on 43 the vehicles in 5-minute departure time windows, with link-level travel times varying by hour of 44 day based on MATSim’s dynamic traffic assignment simulation software. 45 1 Results show that each SAV is able to replace around 9 conventional vehicles within the 24 mi x 2 12 mi area while still maintaining a reasonable level of service (as proxied by user wait times, 3 which average just 1.0 minutes). Additionally, approximately 8 percent more vehicle-miles 4 traveled (VMT) may be generated, due to SAVs journeying unoccupied to the next traveler, or 5 relocating to a more favorable position in anticipation of next-period demand.