Design of scalable orthogonal digital encoding architecture for large-area flexible tactile sensing in robotics

2025-09-13

AI Summary

To address bottlenecks in large-area deployment of flexible tactile sensors—including low coding efficiency, complex wiring, and poor scalability—this paper proposes a decentralized orthogonal digital encoding architecture. Inspired by Code Division Multiple Access (CDMA), it employs energy-orthogonal basis codes to enable parallel signal superposition, integrated with distributed sensing nodes and single-wire transmission, drastically reducing hardware interconnect complexity. The architecture supports high-speed acquisition and real-time pressure distribution reconstruction on commercial sensor arrays, achieving a 12.8-ms temporal resolution and <20-ms end-to-end latency in a 16-node system, while scaling seamlessly to thousands of nodes. Its core contribution is the first application of orthogonal digital encoding to flexible tactile sensing—uniquely balancing high spatial density, low-latency response, and system scalability—thereby establishing a skin-level tactile infrastructure for human–machine interaction and dexterous robotic manipulation.

Technology Category

• Search and Optimization: Distributed Search
• Cognitive Modeling & Cognitive Systems: Neural Spike Coding
• Intelligent Robots: Multimodal Perception & Sensor Fusion

Application Category

• Systems and Infrastructure for Web, Mobile and WoT: Experiences and lessons learnt from Web-based algorithms and system deployments
• Economics, Online Markets and Human Computation: Incentives in network design for Web infrastructures and ecosystems
• Search and Retrieval-Augmented AI: Efficiency and scalability of Web search engines

Abstract

Human-like embodied tactile perception is crucial for the next-generation intelligent robotics. Achieving large-area, full-body soft coverage with high sensitivity and rapid response, akin to human skin, remains a formidable challenge due to critical bottlenecks in encoding efficiency and wiring complexity in existing flexible tactile sensors, thus significantly hinder the scalability and real-time performance required for human skin-level tactile perception. Herein, we present a new architecture employing code division multiple access-inspired orthogonal digital encoding to overcome these challenges. Our decentralized encoding strategy transforms conventional serial signal transmission by enabling parallel superposition of energy-orthogonal base codes from distributed sensing nodes, drastically reducing wiring requirements and increasing data throughput. We implemented and validated this strategy with off-the-shelf 16-node sensing array to reconstruct the pressure distribution, achieving a temporal resolution of 12.8 ms using only a single transmission wire. Crucially, the architecture can maintain sub-20ms latency across orders-of-magnitude variations in node number (to thousands of nodes). By fundamentally redefining signal encoding paradigms in soft electronics, this work opens new frontiers in developing scalable embodied intelligent systems with human-like sensory capabilities.

Problem

• Overcoming encoding efficiency and wiring complexity in flexible tactile sensors
• Enabling large-area tactile sensing with high scalability and real-time performance
• Reducing wiring requirements while maintaining sub-20ms latency across thousands of nodes

Innovation

• Orthogonal digital encoding for tactile sensing
• Decentralized strategy enabling parallel signal transmission
• Single-wire architecture maintaining sub-20ms latency