Strain sensor with improved sensitivity

A strain sensor comprising:

• a body including a first elastic layer and second elastic layer, wherein a conductive layer is disposed between the first elastic layer and the second elastic layer;
• wherein the conductive layer includes a conductive material configured to change in resistance or capacitance based on strain;
• and
• wherein an exposed surface of the second elastic layer is provided with unevenness, and
• wherein the body is configured such that strain imposed on the uneven surface in a side direction of the second elastic layer concentrates strain in valleys of the second elastic layer and generates a change in resistance or capacitance of the conductive layer.

A strain sensor comprising:

• an elastic body having a conductive material uniformly distributed therein, the conductive material configured to change in resistance or capacitance based on strain;
• wherein the elastic body has a first surface, a second surface subtending the first surface, a third surface, and a fourth surface subtending the third surface,
• wherein the first surface is provided with unevenness,
• wherein the third surface is provided with a first electrode and the fourth surface is provided with a second electrode, and
• wherein the elastic body is configured such that when strain is imposed on the first surface in a side direction of the first surface, the strain is concentrated in valleys of the first surface and a change in resistance or capacitance is detected between the first and second electrodes.