LuxTrace: indoor positioning using building illumination

Abstract

Summary. Tracking location is challenging due to the numerous constraints of practical systems including, but not limited to, global cost, device volume and weight, scalability and accuracy; these constraints are typically more severe for systems that should be wearable and used indoors.We investigate the use of wearable solar cells to track changing light conditions (a concept that we named LuxTrace) as a source of user displacement and activity data. We evaluate constraints of this approach and present results from an experimental validation of displacement and activity estimation. The results indicate that a distance estimation accuracy of 21 cm (80% quantile) can be achieved.A simple method to combine LuxTrace with complementary absolute location estimation methods is also presented. We apply carpet-like distributed RFID tags to demonstrate online learning of new lighting environments.

Evolution of Indoor Positioning Technologies: A Survey

“…The idea of exploiting the measurement of known light sources is at the root of works like Randall's LuxTrace [78]. In this work, standard solar cells are used to register luminosity (intensity of light), besides their intended use to collect energy.…”

“…Journal of Sensors noticed that the privacy and security issues regarding the user's location are only addressed in very few projects [24,99,100]. Nevertheless, some authors provide evidence that these factors may influence the adoption and use of the IPS [5,78] or argue that the system must give the users the possibility of deciding whether they want to share their locations with others [78]. Though privacy has been a concern since the very beginning of the development of IPS systems, in the future, this will become one of the main considerations for the adoption or choice of specific IPS systems.…”

Sensing, Computing, and Communications for Energy Harvesting IoTs: A Survey

“…1) Localization and Positioning: Because different locations experience different lighting conditions under the same lighting infrastructure, it is possible to detect location by analyzing the received lights. In [82], [83], the authors proposed and prototyped a wearable solar cell based indoor positioning system called LuxTrace. In their prototype, solar cells are attached to the shoulder of the user, which not only harvest energy from the ambient indoor light, but detect the received light strength (RLS).…”

A Generalized Model for Indoor Location Estimation Using Environmental Sound from Human Activity Recognition

“…Other approaches use light as an information source to estimate the location of the user. Randall et al [20] proposed the use of solar cells, and recorded the patterns as a fingerprint to recognize the location of the user. The deployment of this proposal needs no infrastructure changes; however, location estimation is calculated as a trajectory and not as a punctual location, and standard solar cells are used to register luminosity (intensity of light) as well as their typical use to collect energy.…”