Mobile Robot Localization Using a Novel Whisker-Like Sensor

TL;DR

This paper introduces a novel whisker-like sensor framework for robot localization and contact estimation in environments where visual sensing is unreliable, demonstrating high accuracy through simulation and physical experiments.

Contribution

It develops virtual sensor models and a structured reasoning framework for contact and localization estimation using a single whisker sensor, independent of physical sensor specifics.

Findings

Contact estimation errors under 7 mm

Effective localization without vision systems

Validated with physical and simulation experiments

Abstract

Whisker-like touch sensors offer unique advantages for short-range perception in environments where visual and long-range sensing are unreliable, such as confined, cluttered, or low-visibility settings. This paper presents a framework for estimating contact points and robot localization in a known planar environment using a single whisker sensor. We develop a family of virtual sensor models. Each model maps robot configurations to sensor observations and enables structured reasoning through the concept of preimages - the set of robot states consistent with a given observation. The notion of virtual sensor models serves as an abstraction to reason about state uncertainty without dependence on physical implementation. By combining sensor observations with a motion model, we estimate the contact point. Iterative estimation then enables reconstruction of obstacle boundaries. Furthermore, intersecting states inferred from current observations with forward-projected states from previous steps allow accurate robot localization without relying on vision or external systems. The framework supports both deterministic and possibilistic formulations and is validated through simulation and physical experiments using a low-cost, 3D printed, Hall-effect-based whisker sensor. Results demonstrate accurate contact estimation and localization with errors under 7 mm, demonstrating the potential of whisker-based sensing as a lightweight, adaptable complement to vision-based navigation.