▎ 摘　　要

NOVELTY - Flexible circuit comprises two or more circuit layers (200-202) separated by insulating layers; nodes (203-206) located on each of the circuit layers; and a processor configured to estimate the distribution of liquid within the circuit from the electrical conductance measured at two or more of the nodes. USE - The flexible circuit is useful for calculating three-dimensional distribution of liquid within circuit and force acting on circuit. ADVANTAGE - The nodes on a single layer are described as lying on the x-z plane, with the layers being spaced apart in the y-direction, though this description is a simplification for ease of reference, particularly as the layers bend and may not remain substantially planar. The nodes may be individually addressable by the processor or may provide their readings in an aggregated form. The measurements taken at the nodes are generally strongly dependent on the current state of the insulating layers. The arrangement of the measurement nodes on multiple circuit layers, each separated by an insulating layer, forms a 3D dynamic reaction matrix. Measurements taken at the nodes allow for the coarse measurement of the properties of the flexible circuit and interpolating between the nodes allows for the estimation of the properties of the entire matrix. The functionality and applicability of the circuit can be further improved by configuring it to measure and/or calculate further relevant parameters. DESCRIPTION OF DRAWING(S) - The drawing shows a schematic diagram of two adjacent circuit layers. Circuit layers (200-202) Nodes (203-206)