1. Presented to 2017 TRB Planning Applications Conference
Accounting for AV/CV in Long-Range Plans Using Current Travel Demand Models
Presented to
2017 TRB Planning Applications Conference

2. The Question
Why are we investing billion$ in capital projects when we are about to encounter a transformative event in how we travel?
Automation
Transportation
Jobs

3. Background
25 MPO’s
13 TMAs
12 Non-TMAs

4. Background
Traffic
Three urban areas in top 12 most congested urban areas (TTI Report)
Houston, Dallas, Austin
Austin has worst congested roadway in Texas

5. Background Models 1 ABM model 24 Trip-based models
4 study areas with full mode choice
Handful with mode shares
Majority are 3- step with direct vehicle generation

6. Background Forecasting AV/CV demand
4th task in larger research supported by TxDOT
How does one measure the potential impacts across the state?
Consistent guidance, approaches and measurable outcomes desired by TxDOT

7. Assumptions 100% vehicle mix
Fully autonomous and connected
Consistent with NHTSA Level 4 definition
Current household auto ownership levels maintained
Relinquish navigation, or
Participate in shared-rides (albeit limited)

8. Assumptions Vision of greater ride-sharing
Carpooling in tours
“Robo-Taxis”
Difficult to predict acceptance or system
Therefore:
Shared-ride splits are held constant, or
Proportionally adjusted based on existing forecasted mode shares

9. Assumptions VMT of unoccupied “robo-taxis” not accounted for in study
All sectors in urban area treated equally
Restrict travel within downtown, for example
Existing external splits held constant

10. Identifying A Study Area
Enumerating demand or system changes, although possible, magnitude of changes may be limited in a majority of MPOs in the State of Texas
Limited appreciable system-wide congestion
Limited transit ridership (no mode choice model)
Narrow peak periods and/or spot congestion

11. Study Area Austin, Texas (CAMPO) Six-county study area
System-wide congestion
Most-congested roadway in Texas
Extreme peaks
Transit component

12. Study Area Austin, Texas (CAMPO) Population growth 64% (2010 to 2040)
Source: Texas State Data Center

13. CAMPO TDM 4-Step travel model
Similar trip generation and distribution models to TxDOT (Texas Package)
Mode choice model
Nested-logit model (auto, transit, non-motorized)
15-trip purposes
Generalized-cost assignment
Develop Input Files
Initialization
Trip Generation
Trip Distribution
Mode Choice
Trip Tables
Trip Assignment
Model Reports
Feedback
Source: CAMPO TDM Validation Report

14. Identifying Scenarios
Balance between reasonable assumptions and optimistic enthusiasm
Fleet turnover
Shared rides
Greater mobility for different cohorts (e.g., age & disabled) ....
Uncertainty
Arguments and counter-arguments

15. Identifying Scenarios
“Typical” items that could be given consideration
TDM
&
AV/CV
Land Use
Freight
External Travel
Trip Length
Trip Generation
Mode Choice
Routes
Time Choices
Network Capacity
Costs
Utility of Travel

16. Identifying Scenarios
Unintended consequences & outcomes
TDM
&
AV/CV
Land Use
Freight
External Travel
Trip Length
Trip Generation
Mode Choice
Routes
Time Choices
Network Capacity
Costs
Utility of Travel
Land Use
Household Location
Retail Scope and Location
Education
Primary & Secondary
Workplace Location
Freight Distribution

17. Scenarios Scenarios S1 S2 S3 S4 S5 S6 2040 MTP Forecast
“Base”
Scenarios S1 S2 S3 S4 S5 S6
2040
MTP
Forecast
Limited increase in EXPWY and FRWY capacity
Increase per hour per lane capacity of FRWY links
Increase arterial capacity by 10%
Proportionally move transit trips to SOV and HOV (2 & 3+) trip tables
Proportionally move transit trips to SOV only trip table
Proportionally move transit trips to HOV trip tables.
Sequential & cumulative results

18. TDM Scenario Assumptions Study limited to system & choice
Model inputs held constant:
Demographics
Household and workplace location
Trip rates
External forecasts
Trip lengths
Observed data non-existent
Imposing assumptions
TDM
Choice
System
Demand

19. Scenario Results AM period results only VMT Speeds Travel Time Delay
VMT per person
Average trip lengths in minutes and miles
Modes

20. Scenario VMT Results Scenarios Base S1 S2 S3 S4 S5 S6 AON 16,795,034
17,187,458
17,947,172
17,993,762
18,112,750
18,124,662
18,055,190
18,270,971

21. Scenario VMT Results

22. Scenario VMT Results
2040 MTP Results “Base”
2040 Scenario 3

23. Scenario Speed Results

24. Scenario Speed & VMT Results

25. Scenario Delay Results

26. Scenario per Person VMT & Delay Results

27. Scenario Avg. Trip Length Results

28. Scenario Avg. Trip Length Results

29. General Scenario Results
Metric
Trend
Vehicle Miles of Travel (VMT)
Region
Per Person
Travel Time
Travel in Uncongested Conditions
Travel in Congested Conditions
Congested Weighted
Speeds
Delay
Average Trip Length
Minutes
Miles
Mode Shares
(Transit)

30. Where Are We Now?
Limited acceptance of placing AV/CV scenario in current plans
Curiosity
Not yet tangible
Leadership and guidance needed to develop consistent approaches and metrics

31. Special Thanks Wade Odell (TxDOT Project Manager) Hao Pang (TTI)
Tom Williams (TTI)

32. Questions?