Reliable Heading Tracking for Pedestrian Road Crossing Prediction Using Commodity Devices

TL;DR

This paper introduces the Orientation-Heading Alignment (OHA) algorithm that accurately tracks pedestrian heading using commodity devices, improving safety by predicting crossings with high precision and early alerts.

Contribution

The paper presents a novel heading tracking algorithm that leverages habitual phone carrying patterns, enabling real-time pedestrian crossing prediction on standard devices.

Findings

OHA reduces heading errors by 3.4 times compared to existing methods.

The model predicts crossings 0.35 seconds before pedestrians enter the road.

Operates efficiently on commodity devices in real-time.

Abstract

Pedestrian heading tracking enables applications in pedestrian navigation, traffic safety, and accessibility. Previous works, using inertial sensor fusion or machine learning, are limited in that they assume the phone is fixed in specific orientations, hindering their generalizability. We propose a new heading tracking algorithm, the Orientation-Heading Alignment (OHA), which leverages a key insight: people tend to carry smartphones in certain ways due to habits, such as swinging them while walking. For each smartphone attitude during this motion, OHA maps the smartphone orientation to the pedestrian heading and learns such mappings efficiently from coarse headings and smartphone orientations. To anchor our algorithm in a practical scenario, we apply OHA to a challenging task: predicting when pedestrians are about to cross the road to improve road user safety. In particular, using 755 hours of walking data collected since 2020 from 60 individuals, we develop a lightweight model that operates in real-time on commodity devices to predict road crossings. Our evaluation shows that OHA achieves 3.4 times smaller heading errors across nine scenarios than existing methods. Furthermore, OHA enables the early and accurate detection of pedestrian crossing behavior, issuing crossing alerts 0.35 seconds, on average, before pedestrians enter the road range.