TacLight: A Six-Axis Soft Optical Tactile Sensor for Physical and Virtual Interaction

TacLight: A Six-Axis Soft Optical Tactile Sensor for Physical and Virtual Interaction | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article TacLight: A Six-Axis Soft Optical Tactile Sensor for Physical and Virtual Interaction Ebrahim Shahabi, Zhaoting Li, Sonal Santosh Baberwal, Andre van der Kraan, and 4 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8238291/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted You are reading this latest preprint version Abstract Tactile sensing is a fundamental enabler of robust interaction in environments characterized by dense and uncertain contacts. Yet, existing tactile sensors remain far from human inspiration: they are often mechanically rigid or restricted in the richness of the signals they provide. This paper aims to make a step towards solving this challenge by introducing TacLight: a compact, camera-free optical tactile sensor capable of detecting all six independent force/torque components—normal, shear, torsional, and twisting forces. The sensor is also capable of localizing the contact point. The sensing principle relies on infrared LEDs that emit light through a transparent porous elastomer, while a thin white reflective layer on top enhances light reflection, with distributed photoresistors registering transmitted intensities. Deformations of the porous medium perturb internal light paths, producing direct variations in the electrical output that encode contact mechanics without computationally heavy reconstruction. TacLight achieves high sensitivity (100 mV/N in the 0–3 N range), maintains excellent linearity (R2 > 0.95) with a 10 mm elastomer layer, and preserves a compact, low-cost, and scalable architecture. Two demonstrations highlight TacLight’s versatility. In human–machine interaction, a joystick-like device enables intuitive drone control in a simulation environment. In robotic manipulation, tactile feedback improves the success rate of an imitation-learning-based peeling task compared with a baseline without tactile sensing. Physical sciences/Engineering/Mechanical engineering Physical sciences/Engineering/Electrical and electronic engineering tactile sensing light-based tactile sensor human-robot interaction (HRI) imitation learning soft sensor control of soft robots Full Text Additional Declarations There is NO Competing Interest. Supplementary Files VideoS1.mp4 TacLight Joystick for Virtual Drone Control VideoS2.mp4 Learning Force-Aware Robot Policy via Imitation Learning Cite Share Download PDF Status: Under Review Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-8238291","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":580665612,"identity":"84c98559-204d-4a3a-8b12-0b3f81907caf","order_by":0,"name":"Ebrahim 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Yet, existing tactile sensors remain far from human inspiration: they are often mechanically rigid or restricted in the richness of the signals they provide. This paper aims to make a step towards solving this challenge by introducing TacLight: a compact, camera-free optical tactile sensor capable of detecting all six independent force/torque components—normal, shear, torsional, and twisting forces. The sensor is also capable of localizing the contact point. The sensing principle relies on infrared LEDs that emit light through a transparent porous elastomer, while a thin white reflective layer on top enhances light reflection, with distributed photoresistors registering transmitted intensities. Deformations of the porous medium perturb internal light paths, producing direct variations in the electrical output that encode contact mechanics without computationally heavy reconstruction. 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