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arXiv · 2207.07993

Relative Position Estimation in Multi-Agent Systems Using Attitude-Coupled Range Measurements

Mohammed Shalaby·Charles Champagne Cossette·James Richard Forbes·Jerome Le Ny
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Abstract

The ability to accurately estimate the position of robotic agents relative to one another, in possibly GPS-denied environments, is crucial to execute collaborative tasks. Inter-agent range measurements are available at a low cost, due to technologies such as ultra-wideband radio. However, the task of three-dimensional relative position estimation using range measurements in multi-agent systems suffers from unobservabilities. This letter presents a sufficient condition for the observability of the relative positions, and satisfies the condition using a simple framework with only range measurements, an accelerometer, a rate gyro, and a magnetometer. The framework has been tested in simulation and in experiments, where 40-50 cm positioning accuracy is achieved using inexpensive off-the-shelf hardware.

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Mohammed Shalaby, Charles Champagne Cossette, James Richard Forbes, Jerome Le Ny. 2022-07-16. Relative Position Estimation in Multi-Agent Systems Using Attitude-Coupled Range Measurements. https://doi.org/10.1109/lra.2021.3067253

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