Shared control is a solution which already showed beneficial effects during experiments for steering control in the automotive sector. It allows improving the lane following performance of the driver by supporting them without losing the benefits of having a human in the loop, as a fallback solution in unexpected situations. This article presents a novel shared control strategy for car steering, using an original two parts method. On the one hand, the feedforward part consists of a trajectory generator based on the simulation of a virtual autonomous vehicle. On the other hand, a mixed H2/H∞ control law constitute the feedback part applied on the difference between the system's state and the virtual system's state. A first benefit of such an architecture is that the two parts can be designed sequentially. Secondly, the virtual vehicle used can lead to any kind of shared control assistance; lane keeping system, but also more generic trajectories such as obstacle avoidance, lane changes, etc… Finally, the sharing level between the human driver and the assistance is made explicit and could be modified on the fly. This strategy was tested by simulating the drivervehicle-road system. Results obtained are satisfying for both lane following and steering sharing between the e-copilot and the driver.
Haptic shared control has proven to be an effective method to assist a driver in controlling a vehicle. This method is now being considered for use in developing strategies for smooth transitions between manual and autonomous driving modes. This paper has two objectives. First, it proposes to adapt an existing haptic shared control strategy to achieve transitions between manual and autonomous modes and to evaluate this approach with real drivers on a driving simulator. Second, it proposes to evaluate four different transition profiles in an obstacle avoidance context. The first profile is a gradual transition from autonomous mode to shared control mode, followed by another transition from shared control mode to autonomous mode once the obstacle is passed. The second is a gradual transition from autonomous mode to manual mode. The third is a binary transition from autonomous mode to manual mode. Finally, in the fourth condition, the driver overrides the autonomous mode. These transition profiles were evaluated in curves and straight lines on a driving simulator. The results first validated the use of the haptic shared control strategy to execute transitions between manual and autonomous modes. The distribution of the torques delivered by the automation system and the driver corresponded to the progression of the expected sharing level. Second, the gradual transitions showed advantages over binary transitions and the override of the autonomous mode, both in terms of steering performance and subjective evaluation.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.