Model Predictive Control Based Trajectory Generation for Autonomous Vehicles - An Architectural Approach

Research in the field of automated driving has created promising results in the last years. Some research groups have shown perception systems which are able to capture even complicated urban scenarios in great detail. Yet, what is often missing are general-purpose path- or trajectory planners which are not designed for a specific purpose. In this paper we look at path- and trajectory planning from an architectural point of view and show how model predictive frameworks can contribute to generalized path- and trajectory generation approaches for generating safe trajectories even in cases of system failures.Comment: Presented at IEEE Intelligent Vehicles Symposium 2017, Los Angeles, CA, US

Learning-based Uncertainty-aware Navigation in 3D Off-Road Terrains

This paper presents a safe, efficient, and agile ground vehicle navigation algorithm for 3D off-road terrain environments. Off-road navigation is subject to uncertain vehicle-terrain interactions caused by different terrain conditions on top of 3D terrain topology. The existing works are limited to adopt overly simplified vehicle-terrain models. The proposed algorithm learns the terrain-induced uncertainties from driving data and encodes the learned uncertainty distribution into the traversability cost for path evaluation. The navigation path is then designed to optimize the uncertainty-aware traversability cost, resulting in a safe and agile vehicle maneuver. Assuring real-time execution, the algorithm is further implemented within parallel computation architecture running on Graphics Processing Units (GPU).Comment: 6 pages, 6 figures, submitted to International Conference on Robotics and Automation (ICRA 2023

Vehicle Rollover Stability And Path Planning In Adas Using Model Predictive Control

Advanced Driver Assistance Systems (ADAS) have been developed in recent years to significantly improve safety in driving and assist driver’s response in extreme situations in which quick decisions and maneuvers are required. Common features of ADAS in modern vehicles include automatic emergency braking (AEB), lane keeping assistance (LKA), electric stability control (ESC), and adaptive cruise control (ACC). While these features are developed primarily based on sensor fusion, image processing and vehicle kinematics, the importance of vehicle dynamics must not be overlooked to ensure that the vehicle can follow the desired trajectory without inducing any instability. In many extreme situations such as object avoidance, fast maneuvering of vehicles with high center of gravity might result in rollover instability, an event with a high fatality rate. It is thus necessary to incorporate vehicle dynamics into ADAS to improve the robustness of the system in the path planning to avoid collision with other vehicles or objects and prevent vehicle instability. The objectives of this thesis are to examine the efficacy of a vehicle dynamics model in ADAS to simulate rollover and to develop an active controller using Model Predictive Control (MPC) to manipulate the front-wheel steering and four-wheel differential braking forces, which are related to active steering as well as dynamic stability control for collision avoidance. The controller is designed using the model predictive control approach. A four degree-of-freedom vehicle model is simulated and tested in various scenarios. According to simulation results, the vehicle controller by the MPC controller can track the predicted path within error tolerance. The trajectories used in different simulation scenarios are generated by the MPC controller

Modelling the effect of sensory dynamics on a driver’s control of a nonlinear vehicle

In previous work a linear model of driver steering control was developed which takes account of human sensory dynamics and limitations. In this paper various approaches to modelling a driver’s control of a nonlinear vehicle are compared. In contrast to research focussed on modelling the optimal driver, the aim of this work is to develop a realistic model of driver steering behaviour. Simulations were run to compare various nonlinear state estimators and controllers. In general a trade-off was found between simulation time, which could also represent mental load, and controller performance. Experiments are planned to compare the results of these simulations against measured steering behaviour from human drivers

Learning Terrain-Aware Kinodynamic Model for Autonomous Off-Road Rally Driving With Model Predictive Path Integral Control

High-speed autonomous driving in off-road environments has immense potential for various applications, but it also presents challenges due to the complexity of vehicle-terrain interactions. In such environments, it is crucial for the vehicle to predict its motion and adjust its controls proactively in response to environmental changes, such as variations in terrain elevation. To this end, we propose a method for learning terrain-aware kinodynamic model which is conditioned on both proprioceptive and exteroceptive information. The proposed model generates reliable predictions of 6-degree-of-freedom motion and can even estimate contact interactions without requiring ground truth force data during training. This enables the design of a safe and robust model predictive controller through appropriate cost function design which penalizes sampled trajectories with unstable motion, unsafe interactions, and high levels of uncertainty derived from the model. We demonstrate the effectiveness of our approach through experiments on a simulated off-road track, showing that our proposed model-controller pair outperforms the baseline and ensures robust high-speed driving performance without control failure.Comment: Accepted to IEEE Robotics and Automation Letters (and ICRA 2024). Our video can be found at https://youtu.be/VXf_prNQnJo Project page : https://sites.google.com/view/terrainawarekinody