Implementation of an Optical Tactile Sensing System with Machine Learning

Abstract

In this study, a cost-effective tactile sensing system based on optical sensing technology was developed. The proposed system consists of a 4×4 sensor array designed for surface shape detection and force-based signal acquisition under external loading. During operation, the applied force is converted into an optical signal, and the acquired sensor outputs are classified by an artificial neural- network (ANN) model. Variations in surface patterns, such as flat, wavy, and edged structures, produce different optical intensity distributions depending on the applied force, enabling the recognition of surface characteristics. Using only 16 sensors, the developed system achieved effective surface classification with a spatial force sensitivity of 2.15 N/cm². The ANN-based model achieved a surface profile identification accuracy of 94.2%. The developed sensing system offers a low-cost and effective solution for applications requiring surface recognition and object classification in automotive, industrial and robotic systems.

Keywords

• Artificial Neural Networks
• Machine Learning
• Optical Tactile Sensors
• Pattern Recognition
• Tactile Sensors

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