Powertrain and Chassis Hardware-in-the- Loop (HIL) Simulation of Ford s Autonomous Vehicle Platform Adit Joshi Research Engineer Automated Driving HIL Simulation Ford Motor Company 1
OUTLINE Autonomous Vehicles Autonomous Vehicle Platform (AVP) HIL Simulation HIL Simulations and Test Results Conclusions 2
AUTONOMOUS VEHICLES 3
WHY AUTONOMOUS VEHICLES? Automotive Industry Autonomous Vehicles Increased safety of ALL road users: Increased safety of ALL road users: Passengers Bicyclists Passengers of other vehicles Pedestrians Source: https://crashstats.nhtsa.dot.gov/api/public/viewpublication/812318 4
WHAT IS AN AUTONOMOUS VEHICLE REALLY? VIRTUAL DRIVER SYSTEM (VDS) AUTONOMOUS VEHICLE PLATFORM (AVP) Source: https://medium.com/@ford/putting-the-car-in-self-driving-cars-5d0280eda99a 5
THE JOURNEY TO FULL AUTONOMY HANDS ON AND FEET ON HANDS OFF OR FEET OFF HANDS AND FEET OFF; EYES ON Source: http://standards.sae.org/j3016_201609/ HANDS, FEET, EYES OFF; BRAIN ON HANDS, FEET, EYES, BRAIN OFF HANDS, FEET, EYES, BRAIN OFF 6
TESTING AUTONOMOUS VEHICLES: VEHICLE TESTING 7
TESTING AUTONOMOUS VEHICLES: SIMULATION Using vehicle testing only RAND Corporation Study o 100 vehicle fleet o 24/7 o 365 days/year o 40 km/hr 17 billion driven km 518 years of testing Simulation will be highly important for testing autonomous vehicles! Multiple variations of multiple scenarios 8
TESTING AUTONOMOUS VEHICLES: SIMULATION Hardware-in-the-Loop (HIL) Simulation 9
TESTING AUTONOMOUS VEHICLES: SIMULATION Hardware-in-the-Loop (HIL) Simulation ECUs tested in a simulated environment Scalability and repeatability of scenarios Improvement in test consistency Reduction in system variation Source: https://www.dspace.com/en/pub/home/medien /papers/article_variant-based_workflow.cfm 10
BUILDING THE AUTONOMOUS VEHICLE PLATFORM: VEHICLE 2017 Ford Fusion Hybrid Power-split type hybrid architecture Source: http://steeringnews.com/wpcontent/uploads/2014/11/ford-fusion-hybriddrivetrain.jpg 11
BUILDING THE AUTONOMOUS VEHICLE PLATFORM: HIL 12
HIL SIMULATIONS AND TEST RESULTS 2017 Ford Fusion Simulink-CarSim HIL Virtual Test Tracks Powertrain and braking correlation o Straight-line track Steering correlation o Steering and handling track Correlation Performance Correlation Coefficient rr = nn nn ii=1 nn nn ii=1 nn VVii NN ii ii=1 VVii nn ii=1 VV 2 ii nn 2 ii=1 VV ii nn ii=1 nn Coefficient of Determination RR 2 = 1 nn ii=1 nn ii=1 VV ii NN ii 2 VV ii 1 nn ii=1 nn 2 VV ii NNii NN 2 ii nn 2 ii=1 NN ii Lateral Trajectory of Test Track (m) Lateral Trajectory of Test Track (m) 1 0.8 0.6 0.4 0.2 0-0.2-0.4-0.6-0.8-1 0 200 400 600 800 1000 1200 Longitudinal Trajectory of Test Track (m) -50-100 -150-200 -250-300 Trajectory of Virtual Straight-Line Test Track Trajectory of Virtual Test Track -350 0 200 400 600 800 1000 1200 Longitudinal Trajectory of Test Track (m) 13
HIL SIMULATIONS AND TEST RESULTS 2.5 2 Powertrain Correlation Correlation Test Results of Acceleration Response (Powertrain) H I L V ehicle 1600 1400 H I L Correlation Test Results of Torque Response (Powertrain) V ehicle Longitudinal Acceleration (m/s 2 ) 1.5 1 0.5 Longitudinal Torque (Nm) 1200 1000 800 0 600-0.5 0 2 4 6 8 10 12 14 Time (s) Response Correlation Coefficient Acceleration 0.9971 0.9823 Torque 0.9778 0.9487 400 0 2 4 6 8 10 12 14 Time (s) Coefficient of Determination 14
HIL SIMULATIONS AND TEST RESULTS Longitudinal Deceleration (m/s 2 ) 2 1.5 1 0.5 0-0.5-1 -1.5-2 Braking Correlation Correlation Test Results of Acceleration Response (Braking) H I L V ehicle Braking Torque (Nm) 200 0-200 -400-600 -800-1000 Correlation Test Results of Torque Response (Braking) H I L V ehicle -2.5-1200 -3 0 2 4 6 8 10 12 Time (s) -1400 0 2 4 6 8 10 12 Time (s) Response Correlation Coefficient Coefficient of Determination Deceleration 0.9902 0.9788 Brake Torque 0.9890 0.9746 15
HIL SIMULATIONS AND TEST RESULTS Steering Wheel Angle (deg) 200 150 100 50 0-50 Steering Correlation Correlation Test Results of Steering Wheel Angle Response (Steering) H I L V ehicle Lateral Acceleration(m/s 2 ) 5 4 3 2 1 0-1 -2-3 Correlation Test Results of Acceleration Response (Steering) H I L V ehicle -100 0 10 20 30 40 50 60 70 Time (s) -4 0 10 20 30 40 50 60 70 Time (s) Response Correlation Coefficient Coefficient of Determination Steering Wheel Angle 0.9669 0.9345 Lateral Acceleration 0.9645 0.9167 16
HIL SIMULATIONS AND TEST RESULTS Longitudinal Acceleration (m/s 2 ) 4 3 2 1 0-1 Simulations over Disturbances: Payload Mass & Ambient Pressure Simulation Test Results of Acceleration/Deceleration Response (Mass Variations) 1815 kg 1915 kg 2015 kg 2115 kg Longitudinal Acceleration (m/s 2 ) 4 3 2 1 0-1 Simulation Test Results of Acceleration/Deceleration Response (Ambient Pressure Variations) 92 kpa 95 kpa 98 kpa 101 kpa -2 0 5 10 15 20 Time (s) -2 0 5 10 15 20 Time (s) 17
HIL SIMULATIONS AND TEST RESULTS Longitudinal Acceleration (m/s 2 ) 4 3 2 1 0-1 Simulations over Disturbances: SOC & Ambient Temperature Simulation Test Results of Acceleration/Deceleration Response (SOC Variations) 0:4 0:6 0:8 1 Longitudinal Acceleration (m/s 2 ) 4 3 2 1 0-1 Simulation Test Results of Acceleration/Deceleration Response (Ambient Temperature Variations) 0 deg C 10 deg C 20 deg C 30 deg C -2 0 5 10 15 20 Time (s) -2 0 5 10 15 20 Time (s) 18
HIL SIMULATIONS AND TEST RESULTS 50 40 30 Simulations over Disturbances: Crosswinds Simulation Test Results of Steering Response (Left Crosswinds Variations) 60 50 40 Simulation Test Results of Steering Response (Right Crosswinds Variations) Steering Wheel Angle (deg) 20 10 0-10 -20 0 km=hr / -30 50 km=hr / -40 100 km=hr / 150 km=hr / -50 0 10 20 30 40 50 60 70 Time (s) Steering Wheel Angle (deg) 30 20 10 0-10 0 km=hr / -20 50 km=hr / / 100 km=hr -30 150 km=hr / -40 0 10 20 30 40 50 60 70 Time (s) 19
CONCLUSIONS Demonstrated need for simulation platform for development of Autonomous Vehicle Platform Powertrain and Chassis HIL simulation Consistent and controlled test environment System variables fixed for automated repeated tests Application of different disturbance conditions for comparison Some vehicle testing moved to HIL simulation Reduction in vehicle needs and corresponding test time 20
CONCLUSIONS Rapid prototyping and testing of the hardware components Real-time performance of HIL simulation correlated with vehicle Repeatability of tests for design of experiments testing in short timeframe Extreme or unsafe driving scenarios tested in safe simulated environment Harsh temperatures High altitudes High crosswinds Low friction surfaces 4 Source: https://www.carsim.com/products/carsim/ 21
QUESTIONS??? 22
BACKUP SLIDES BACKUP SLIDES 23
TESTING AN AUTONOMOUS VEHICLE: VEHICLE TESTS https://www.youtube.com/watch?v=vwfdt0ocsjg https://www.youtube.com/watch?v=xjpy1jxfgjk https://www.youtube.com/watch?v=-ah-p6zigjw 24