Pedestrian tracking using an IMU array

Ubiquitous and accurate tracking of pedestrians are an enabler for a large range of emerging and envisioned services and capabilites. To track pedestrians in prevailing indoor environments, inertial measurement units (IMUs) may be used to implement foot-mounted inertial navigation. Today emerging ultra-low-cost IMUs are taking a leading role in the advancement of the IMU performance-to-cost boundary. Unfortunately, the performance of these IMUs are still insufficient to allow extended stand-alone tracking. However, the size, price, and power consumption of single-chip ultra-low-cost IMUs makes it possible to combine multiple IMUs on a single PCB, creating an IMU array. The feasibility of such hardware has recently been demonstrated. On the other hand, the actual gain of using such multi-IMU systems in the pedestrian tracking application is unclear. Therefore, based on an in-house developed IMU array, in the article we demonstrate that foot-mounted inertial navigation with an IMU array is indeed possible and benefitial. The error characteristics of the setup and different ways of combining the inertial measurements are studied and directions for further research are given.