Pedestrian Tracking with Shoe-Mounted Inertial Sensors

TLDR

A navigation system that tracks a person on foot is useful for emergency responders, location‑aware computing, personal navigation, mobile 3D audio, and mixed/augmented reality, yet current position‑tracking technologies require instrumented, marked, or premapped environments. The authors developed NavShoe, a shoe‑mounted inertial‑sensing system for position tracking. NavShoe employs a small, low‑power wireless inertial sensor that fits into the shoelaces and can operate all day on a small battery. NavShoe delivers meter‑level position accuracy and highly accurate foot orientation, greatly reduces computer‑vision search space, and is robust for outdoor use, though it cannot alone precisely register close‑range objects.

Abstract

A navigation system that tracks the location of a person on foot is useful for finding and rescuing firefighters or other emergency first responders, or for location-aware computing, personal navigation assistance, mobile 3D audio, and mixed or augmented reality applications. One of the main obstacles to the real-world deployment of location-sensitive wearable computing, including mixed reality (MR), is that current position-tracking technologies require an instrumented, marked, or premapped environment. At InterSense, we've developed a system called NavShoe, which uses a new approach to position tracking based on inertial sensing. Our wireless inertial sensor is small enough to easily tuck into the shoelaces, and sufficiently low power to run all day on a small battery. Although it can't be used alone for precise registration of close-range objects, in outdoor applications augmenting distant objects, a user would barely notice the NavShoe's meter-level error combined with any error in the head's assumed location relative to the foot. NavShoe can greatly reduce the database search space for computer vision, making it much simpler and more robust. The NavShoe device provides not only robust approximate position, but also an extremely accurate orientation tracker on the foot.