Smart Device Development for Gait Monitoring: Multimodal Feedback in an Interactive Foot Orthosis, Walking Aid, and Mobile Application

TL;DR

This study presents a modular, sensorized system that combines a smart foot orthosis, an instrumented forearm crutch, and a mobile app to deliver real-time vibrotactile feedback for gait rehabilitation. The authors validate system feasibility against an instrumented treadmill, assess mobile app usability, and compare two vibrotactile feedback modalities across devices, finding that pattern-based pulsed feedback is generally preferred and device location influences perception. The work demonstrates the potential of a closed-loop, multimodal feedback platform to support patient-centered gait therapies and informs design considerations for future intelligent orthotic devices. While promising, the study notes limitations in sample size and laboratory conditions, outlining concrete directions for real-world validation, expanded cohorts, and richer feedback strategies. Overall, this integrated approach advances gait monitoring and haptic rehabilitation by linking sensing, feedback, and data interpretation in daily-life contexts.

Abstract

Smart assistive technologies such as sensor-based footwear and walking aids offer promising opportunities for gait rehabilitation through real-time feedback and patient-centered monitoring. While biofeedback applications show great potential, current research rarely explores integrated closed-loop systems with device- and modality-specific feedback. In this work, we present a modular sensor-based system combining a smart foot orthosis and an instrumented forearm crutch to deliver real-time vibrotactile biofeedback. The system integrates plantar pressure and motion sensing, vibrotactile feedback, and wireless communication via a smartphone application. We conducted a user study with eight participants to validate the system's feasibility for mobile gait detection and app usability, and to evaluate different vibrotactile feedback types across the orthosis and forearm crutch. The results indicate that pattern-based vibrotactile feedback was rated as more useful and suitable for regular use than simple vibration alerts. Moreover, participants reported clear perceptual differences between feedback delivered via the orthosis and the forearm crutch, indicating device-dependent feedback perception. The findings highlight the relevance of feedback strategy design beyond hardware implementation and inform the development of user-centered haptic biofeedback systems.

Figures (10)

• Figure S1: Overview of the sensor-based assistive system consisting of a smart orthosis with integrated FSR and IMU sensors, vibration feedback, and its communication with a walking aid and an mHealth application for interactive gait monitoring.
• Figure S2: (a) Overview of the orthosis prototype and assembled components; (b) Final assembled prototype of the smart insole.
• Figure S3: (a) Hardware block diagram of the smart walking aid; (b) Final assembled prototype with integrated electronics.
• Figure S4: Overview of the data processing for gait data extraction of the smart foot orthosis.
• Figure S5: Screenshots of the developed mHealth app showing key interface components, including account creation, main menu navigation, plantar pressure heatmap, gait diary, exercise tutorials, and access to foot health resources.