The mechanical latching memory of an adhesive tape

TL;DR

This paper investigates how adhesive tape can mechanically store and retrieve memory of peeling cycles, demonstrating a new rectified memory principle with potential for mechanical computing applications.

Contribution

It introduces a novel rectified memory mechanism in adhesive tape, showing how it can be used for multiple memory storage, partial erasure, and feature extraction in mechanical computing.

Findings

Tape exhibits multiple-memory behavior similar to return-point memory.

Memory can be partially erased and manipulated.

Tape can function as a mechanical feature extractor and comparator.

Abstract

The storage and retrieval of mechanical imprints from past perturbations is a central theme in soft matter physics. Here we study this effect in the partial peeling of an ordinary adhesive tape, which leaves a line of strong adhesion at the stopping point. We show how this behavior can be used to mechanically store and retrieve the amplitudes of successive peeling cycles. This multiple-memory behavior resembles the well-known return-point memory found in many systems with hysteresis, but crucially the driving here is rectified: peeling is unidirectional, where each cycle begins and ends with the tape flat on the substrate. This condition means that the tape demonstrates a distinct principle for multiple memories. By considering another mechanism that was recently proposed, we establish ``latching'' as a generic principle for memories formed under rectified driving, with multiple physical realizations. We show separately that tape can be tuned to erase memories partially and also demonstrate the function of tape as a mechanical computing device that extracts features from input sequences and compares successive values.