Automotive Research in Vehicle Dynamics Laboratory Introduction Active Safety Hybrid and Fuel Cell Vehicles Conclusions Huei Peng Department of Mechanical Engineering The University of Michigan

Vehicle Dynamics Laboratory Professor Huei Peng Currently 12 Ph.D. students, 1 M.S. student and 5 visiting scholars Huei Peng Research Summary 2008/02/11 -

Major Issues of Ground Vehicles Sustainability Energy Environment Quality/Functionality Safety Workforce Huei Peng Research Summary 2008/02/11 -

Outline Introduction Active Safety Hybrid and Fuel Cell Vehicles Conclusions Huei Peng Research Summary 2008/02/11 -

Active Safety Research Chassis Control ESC, road departure warning, CW/CA, Rollover prediction and prevention, Active Suspension, Integrated Chassis Control Worst-case evaluation methodology Driver model development through naturalistic driving database Huei Peng Research Summary 2008/02/11 -

Active Safety Technologies Rollover generation, prediction and prevention ACC effect on Traffic flow 5.5 km, 2 lanes Performance evaluation of VDC Driver model development Huei Peng Research Summary 2008/02/11 -

Worst-Case Evaluation Method Human driver Model Standard test matrix Worst-case test matrix DAS design Open-loop Simulations Worst-case Simulations HIL Simulations Field tests Design Iteration Doi, Nagiri and Amano, Toyota 1998 Huei Peng Research Summary 2008/02/11 -

Mathematical Formulation Given a nonlinear vehicle dynamic model , where the disturbance input includes front wheel steering angle and brake pedal command . The control input includes the ABS pressure command , CDC damping and VDC pressure command . The control algorithms of the ABS and VDC modules are assumed to be known. Find, within saturation bound and , the signal which maximizes a cost function . The matrix Q is selected such that the vehicle side slip or roll angle is maximized. Huei Peng Research Summary 2008/02/11 -

Worst-case Library A rollover-worst-case database was created. Many result in rollovers, the rest at least single wheel lift-off. Useful for VDC evaluation and re-design. Huei Peng Research Summary 2008/02/11 -

Vehicle or ESC Performance Evaluation Huei Peng Research Summary 2008/02/11 -

Rollover Accident due to an Initial Sideswipe Collision Huei Peng Research Summary 2008/02/11 -

Rollover Accident Simulation & Avoidance by PISC Without Control With PISC Control Huei Peng Research Summary 2008/02/11 -

Rollover Accident at an Intersection Huei Peng Research Summary 2008/02/11 -

Accident Reconstruction & Control Comparison Red sedan: bullet vehicle Blue sedan: target vehicle without post-impact control Yellow sedan: target vehicle with post-impact control Huei Peng Research Summary 2008/02/11 -

Comparison of Trajectories * 1 sec after impact  3 sec after impact 3 lane width Huei Peng Research Summary 2008/02/11 -

Vehicle Motion Databases SAVME Urban street Large human driver population but shorter horizon (<15 seconds) ICC FOT Highway + local roads (naturalistic use) Relatively longer cases (<200 seconds) ACAS RDCW Huei Peng Research Summary 2008/02/11 -

SAVME data collection & archiving System for Assessment of the Vehicle Motion Environment 30,561 vehicles, Plymouth road, Ann Arbor, MI, USA Digital video cameras 100ft 200 ft 600 ft Huei Peng Research Summary 2008/02/11 -

ICC FOT database 108 drivers. Mostly highway In car instrumentations Width 4.4m Host Vehicle Side beam (32m) Main beam(133m) 108 drivers. Mostly highway In car instrumentations 114,000 total miles (68,000 miles manual) http://www.itsdocs.fhwa.dot.gov/jpodocs/repts_te/l@01!.pdf http://www.itsdocs.fhwa.dot.gov/jpodocs/repts_te/94z01!.pdf Intelligent Cruise Control Field Operational Test Observation of intelligent cruise control system operatability in naturalistic use Equipped with infra-red laser sensors of up to 133m range 108 drivers participated for 2 ~ 5 weeks each Data without cruise control/adaptive cruise control extracted and used Huei Peng Research Summary 2008/02/11 -

ACAS FOT Database Total traveled distance: 137,000 miles, 1,500 miles per driver. Database: 164 GB in volume; contains approx. 400 engineering variables sampled at 10 Hz, as well as synchronized road forward-view video clips. Huei Peng Research Summary 2008/02/11 -

Road Departure Crash Warning System Database 11 test vehicles Nissan Altima 2003 78 FOT drivers Evenly by gender Three age groups 82,773 miles of driving 2,487 hours Over 400 signals captured at 10 Hz or faster 204 GB numerical data 135 GB video data Huei Peng Research Summary 2008/02/11 -

Outline Introduction Active Safety Hybrid and Fuel Cell Vehicles Conclusions Huei Peng Research Summary 2008/02/11 -

Hybrid Vehicles Studied FCHV DCX Natrium (2005) HHV Super-HMMWV (2006) Super-HMMWV (2007) FMTV (2002) HEV International Truck (2001) Eaton/Fed Ex (2004) Super-HMMWV (2006) FTTS (2000) Series Parallel Split Huei Peng Research Summary 2008/02/11 -

Key Problems in Hybrid Vehicle Design Configuration selection and model generation Component sizing Control DP/SDP algorithms as the assessment tool/benchmark SDP/other algorithms for implementation Vehicle Model Fuel consumption, Distance Input state Output state Power demand Power error Throttle Gear shift AFM Mode Power Split EVT Vehicle Engine M/G2 M/G1 Battery Huei Peng Research Summary 2008/02/11 -

Possible Design Process Automatically-Generated Dynamic Models Selection of the powertrain configuration Selection of the mechanical parameters Selection of the powertrain component sizes Model Based DP Control Theoretical best performance (non-causal) iteration Model Based SDP or ECMS Control Implementable control strategies Huei Peng Research Summary 2008/02/11 -

Summary The main research objectives of the Vehicle Dynamics Laboratory at the Michigan Ann Arbor are to enhance the safety/energy/environment performance of ground vehicle—through working with and education top graduate students. Environment Education Energy Safety Huei Peng Research Summary 2008/02/11 -