Robust Indoor Localization in a Reverberant Environment Using Microphone Pairs and Asynchronous Acoustic Beacons

In this paper, a robust indoor localization method using microphone pairs and asynchronous acoustic beacons was proposed. The proposed method is applicable even with a two-channel microphone pair, which is the minimal configuration of a microphone array. The proposed method estimates location by using the cross-correlation functions of the measured signals as location likelihoods. Three experiments were conducted to evaluate the proposed method. Four beacons were located at the corners of a localizing area of 4 m by 4 m and emitted signals with a bandwidth of 2 kHz. The localization results were compared to the previous method with deterministic direction-of-arrival estimation. The 90th percentiles of the localization error were 0.23 m for the proposed method with two microphones, 0.19 m for the proposed method with four microphones, and 0.30 m for the previous method under conditions without significant reverberation. Under a condition with reflective walls, the 90th percentile of the localization error of the previous method increased to 0.49 m, while that of the proposed method was only increased to 0.23 m for two microphones and 0.19 m for four microphones. The proposed method contributes to a robust localization in indoor environments and relieves the constraints of receiver configuration

Project overview on multimodal XR-AI platform for tele-rehab and the reciprocal care coupling with health guidance

The purpose of this project is to mitigate and solve issues regarding health care services such as rehabilitation and specific health guidance while alleviating spatio-temporal, economic, and cognitive constraints by establishing remote technology foundation. There are four themes in this project titled “Multimodal XR-AI (XR powered by AI) platform development for tele-rehabilitation and the reciprocal care coupling with health guidance.” In theme #1, we have been developing MR3 (Multi-Modal Mixed Reality for Remote Rehab) devices consisting of Wear and Mannequin for supporting detailed assessments of customers’ physical functions and tactile interaction respectively. The central issue of theme #2 is to support intrinsic motivation for rehabilitation and exercise training through XR technologies as in virtual co-embodiment and hand redirection. In addition, we have also been investigating how to deal with one-to-many (a small number of providers) and zero-to-many (no providers) situations. Theme #3 has aimed on establishing AI technology foundation for creating, monitoring progress of, and updating tele-rehab programs mainly for the upper limb. Systems for always-on monitoring during daily life and work developed in theme #4 is expected to be served as a common foundation for various tele-healthcare services.</p