Example-Based Query To Identify Causes of Driving Anomaly with Few Labeled Samples

Abstract

Driving anomaly detection is important for advanced driver assistance systems (ADAS) to increase driving safety and avoid traffic accidents. However, driving anomaly detection faces many challenges such as numerous and uncertain abnormal patterns observed on the road, sparsity of real anomaly cases documented with accurate labels, and rigid existing systems that rely on manually set thresholds and rules. Previous studies have proposed unsupervised methods for driving anomaly detection in the driver’s behaviors or the road condition by identifying deviations from normal driving conditions. A challenge with unsupervised models is the lack of interpretability, where the cause of the anomaly is not always clear. We address this problem with an example-based query method that combines unsupervised anomaly detection methods with the multi-label k-nearest neighbors (ML-KNN) algorithm to interpret the detected driving anomalies by identifying their possible causes (e.g., surrounding objects or driver’s errors). Our approach relies on a few manually labeled driving segments that are efficiently used as anchors to retrieve the causes of driving anomalies in a given driving segment. These anchors are projected into the embedding created by unsupervised driving anomaly detection systems. The experimental results show that this method can effectively identify the causes of driving anomalies, even for abnormal driving segments triggered by multiple causes. The evaluation shows the flexibility of our proposed solution, where we successfully implement the ML-KNN approach with three alternative feature representations.