Light-based tactile sensing with directional sensitivity

A device comprising:

• a substrate;
• and
• a set of force sensors supported by the substrate, each force sensor of the set of force sensors comprising:
• a pillar extending outward from the substrate, each pillar comprising a stack of semiconductor layers, the stack of semiconductor layers being configured to emit light upon biasing of the stack of semiconductor layers;
• and
• a post disposed along only a portion of a perimeter of the pillar such that, taken together, the pillar and the post have an asymmetrical cross-sectional shape;
• wherein each pillar has a cross-section elongated along an axis, and
• wherein an orientation of the axis, and a peripheral position of the portion of the perimeter at which the post is disposed, differ across the set of force sensors such that a variation in light emitted by the stack of semiconductor layers of one or more of the force sensors of the set of force sensors is indicative of a direction of a shear force applied to the set of force sensors.