Apple Patent | Fabric-based devices with force sensing

Patent: Fabric-based devices with force sensing

Publication Number: 10180721

Publication Date: 2019-01-15

Applicants: Apple

Abstract

A fabric-based item such as a fabric glove may include force sensing circuitry. The force sensing circuitry may include force sensor elements formed from electrodes on a compressible substrate such as an elastomeric polymer substrate. The fabric may include intertwined strands of material including conductive strands. Signals from the force sensing circuitry may be conveyed to control circuitry in the item using the conductive strands. Wireless circuitry in the fabric-based item may be used to convey force sensor information to external equipment. The compressible substrate may have opposing upper and lower surfaces. Electrodes for the force sensor elements may be formed on the upper and lower surfaces. Stiffeners may overlap the electrodes to help decouple adjacent force sensor elements from each other. Integrated circuits can be attached to respective force sensing elements using adhesive.

Background

It may be desirable to form items using materials such as fabric. For example, wearable items may be formed from fabric. Some wearable items may include sensing circuitry. Electronic equipment may use information from the sensing circuitry in controlling a system or performing other tasks.

If care is not taken, fabric-based items such as these may not offer desired features. For example, a fabric-based item with sensing circuitry may be awkward to use, may not have an attractive appearance, or may not gather measurements accurately.

Summary

A fabric-based item such as a fabric glove may include force sensing circuitry. The force sensing circuitry may include force sensor elements formed from electrodes on a compressible substrate such as an elastomeric polymer substrate. The fabric may include intertwined strands of material including conductive strands. Signals from the force sensing circuitry may be conveyed to control circuitry in the item using the conductive strands. Wireless circuitry in the fabric-based item may be used to convey force sensor information to external equipment.

The compressible substrate may have opposing upper and lower surfaces. Electrodes for the force sensor elements may be formed on the upper and lower surfaces. Stiffeners may overlap the electrodes to help decouple adjacent force sensor elements from each other. In some configurations, integrated circuits can be attached to respective force sensing elements using adhesive.

Force sensing elements may have sets of electrodes that are arranged in an array on the compressible substrate such as a one-dimensional array. The compressible substrate may be formed from an elongated strip of the elastomeric polymer and may be sufficiently elongated to serve as a strand that is intertwined with the conductive strands and other intertwined strands of material in the fabric.

To facilitate deformation of the compressible substrate, the compressible substrate may be provided with openings surrounding the electrodes of each force sensor element. Electrodes, signal traces for conveying capacitive force sensor signals, shield structures, and other conductive signal paths in the force sensing circuitry may be formed from structures that resist cracking when flexed such as mesh structures with serpentine line segments.