Nexa · Android

A body built to human specification.

Not a human-shaped machine — a body matched to the human mechanism: tendon-driven muscle, full-body sensing skin, and a skeleton held to the same proportions and physical limits as ours.

Two Nexa androids facing one another.

Dexterous face

Reverse-engineering 40 facial muscles

Expression is not a texture problem. Each muscle is studied for its motion effect, then a lattice structure is designed backwards from that effect to form a micro actuation unit — so expressions emerge from muscle, the way they do in a face.

Exterior / anatomy comparisonFIG. 04

Dexterous face system

Reverse-engineering 40 facial muscles.

Natural expression begins beneath the surface. Nexa maps facial muscles to lattice actuation units so fine movement emerges from anatomy rather than a surface animation.

39

Facial degrees of freedom

38/60

FACS action units

Lattice bionic muscle unit.
Lattice bionic muscle unitReverse-designed from each facial muscle's motion effect to coordinate fine expression without depending on playback.

Perception system

Whole-body multimodal sensing

A bionic sensing network spanning vision, touch, force, position, motion and physiological signal — fused, aligned, and resolved into a single body-state estimate.

System capabilities

01

Multimodal coverage

Vision · touch · force · position · motion · physiology

02

Fusion and alignment

Spatiotemporal synchronisation, cross-modal mapping

03

State estimation

Pose · contact · load · balance · motion trend

04

Capture and reconstruction

Motion reconstruction, closed-loop feedback

Modalities and sensors

Touch / force

High-density tactile array · six-axis force sensor

Vision

RGB-D / stereo · first-person view

Audition

Microphone array · bone conduction

Position / deformation / motion

IMU / positional markers · deformation sensors

Physiological

Heart rate · respiration · EMG · surface temperature · thermal distribution

Unified body-state output

Whole-body poseContact distributionLoad stateBalance and stabilityMotion trendInteraction state
Nexa full-body multimodal perception network.

Face

Micro-expression / EDA / thermal

Perception fuses into one unified body state — knowing where it is, how it is touched, and how to respond.

Biofidelity Benchmark

Six layers, in full

Nexara and the Society for Android Science jointly define a six-layer Biofidelity Benchmark — turning “human-like” from a marketing adjective into a standard you can measure layer by layer.

What cannot be measured cannot be built.

Each layer names what it evaluates, the question it answers, and the metrics it answers it with. Layers are measured independently — a system can hold at L3 and fail at L5.

LayerEvaluatesCore questionExample metrics
L1

Morphological Fidelity

Body form, skeleton, anatomical structureDoes it look like a human?Body proportion · Skeletal structure · Joint axes · Muscle layout · Facial proportion
L2

Biomechanical Fidelity

The motion systemDoes it move like a human?Range of motion · Gait · Postural stability · Joint torque · Energy consumption · Motion smoothness
L3

Biophysical Fidelity

Skin, soft tissue, temperature, contactDoes it feel like a human?Young's modulus · Rebound · Surface temperature · Coefficient of friction · Skin texture
L4

Sensorimotor Fidelity

Perception and bodily feedbackDoes it sense its own body the way a human does?Tactile density · Visual coverage · Proprioception · State estimation · Response latency
L5

Expressive Fidelity

Expression, gaze, voice, postureCan it express human emotion?Expression accuracy · Vocal affect · Gaze naturalness · Lip-sync · Gestural semantic consistency
L6

Social Fidelity

Long-horizon interactionIs it treated as a real person?Trust score · Uncanny valley · Likability · Persona consistency · Long-term acceptance

L1 to L6 runs from looking like a human to being treated as one. Fidelity accumulates; a layer is only meaningful once the layers beneath it hold.

Why it exists

A standard is not a marketing asset

A robot optimises for the best solution. An android optimises for the human one.

Conventional robotics scores itself on task performance — faster, stronger, more efficient. An android is scored on human fidelity. Those are different objective functions, and they need different yardsticks.

A benchmark is what makes a field a discipline

Protein structure had the PDB. Vision had ImageNet. Without a shared, published measure, every claim about human likeness is unfalsifiable — and a field of unfalsifiable claims never becomes a science.

It is also an acceptance spec

The same six layers that let researchers compare systems let a licensee write verification criteria into a contract. One standard, two uses.

Method

Evaluation data is held apart from training data

The Human Foundation Dataset feeds two consumers: benchmark evaluation and model training. The two are isolated by purpose, so a system is never scored against the data it learned from.

Licensing Nexa

Nexara does not sell to consumers. What we build is licensed to a small number of partners.