“Can You Handle the Truth?”: Investigating the Effects of AR-Based Visualization of the Uncertainty of Deep Learning Models on Users of Autonomous Vehicles

The recent advances in deep learning have paved the way for autonomous vehicles (AVs) to take charge of more complex tasks in the navigation process. However, predictions of deep learning models are subject to different types of uncertainty that may put the user and the surrounding environment in danger. In this paper, we investigate the effects that AR-based visualizations of 3 types of uncertainties in deep learning modules for path planning in AVs may have on drivers. The uncertainty types of the deep learning models that we consider are: the waypoint uncertainty, the situation uncertainty, and the path uncertainty. We propose 3 concepts to visualize the 3 uncertainty types on a Windshield display. We evaluate our AR-based concepts with a user study $(\mathrm{N}=20)$ using a VR-based immersive environment, to ensure the security of the participants. The results of our evaluation reveal that the absence of uncertainty visualization leads to lower driver engagement. More importantly, the combination of situation uncertainty and path uncertainty visualizations leads to higher driver engagement, and higher trust in the automated vehicle, while inducing an acceptable mental load for the drive.