Architectural Foundations of
Touchable^® Cardiovascular Surfaces

The prevailing model of physiological sensing remains spatially constrained and behaviorally dependent. Many deployments rely on point-based acquisition, often through worn devices or fixed sensor sites, and depend on deliberate user participation.

Touchable Cardiovascular Surfaces (TCS) depart from that model. TCS is a surface-level physiological sensing architecture designed to transform passive touch surfaces into contact-conditioned physiological interfaces while preserving the familiar behavior of the host surface. It achieves this through distributed photonic sensing locations that may be admitted locally during touch, evaluated for suitability, and routed into a disciplined output stream aligned with host integration.

This whitepaper defines the core architecture of TCS, including its sensing stack, control hierarchy, suitability gating and selection logic, power posture, and integration model. The platform perspective is central: TCS is not merely a sensor placed under a surface. It is a surface-level sensing architecture that coordinates sensing, admission, and disciplined export.

TCS can be described as a surface-level physiological sensing architecture, not as a conventional point sensor relocated into a larger area. In typical deployments, the surface can remain low-activity until interaction at the surface interface is detected. When interaction occurs, the system may admit a localized region of interest, evaluate multiple candidate sensing locations associated with that region, and select one or more suitable signals for downstream processing based on configured criteria. As interaction geometry shifts over time, selection may adapt to preserve continuity without imposing a new user ritual.

At a high level, a sensing location within a TCS surface can include an illumination element configured to support optical sensing of blood-volume-related changes in tissue, a sensing element for optical acquisition, interface circuitry supporting localized activation and signal acquisition, and control connectivity to a shared coordination layer.

This architecture shifts surface sensing away from fixed placement and persistent polling, toward contact-conditioned admission, local suitability gating, and disciplined export aligned to the host system.

TCS is organized around an event-driven surface behavior: sensing resources can be engaged in response to contact, rather than acquired continuously across an entire field. This is the architectural inverse of many sensor arrays that treat sensing as an ongoing scan.

This control hierarchy is a defining element of the topology: it turns a dense surface into a disciplined physiological interface rather than an unbounded collection of raw channels.

TCS can be understood as temporally continuous during interaction while remaining spatially conditional.

• Temporal acquisition can be sustained during contact sessions when policy and integration call for it.
• Spatial participation can remain bounded to admitted regions and candidate subsets rather than spanning a full surface field.
• Acquisition and processing can be scheduled and coordinated in a way that balances signal continuity with power and thermal constraints.

The key is architectural: TCS treats spatial admission and suitability gating as the mechanism that makes surface-level physiological capture practical and stable. It avoids the failure mode of treating the entire surface as one aggregated analog source, which can dilute or corrupt physiological signal structure when unrelated regions are mixed.

TCS is engineered around local activation.

• In quiescent states, large portions of the surface may remain in low-activity modes.
• During interaction, resources can be concentrated in the admitted region and associated candidate subset.
• In some embodiments, downstream streaming can focus on one selected signal at a time; other embodiments may support multiple signals depending on use case and policy.

This posture supports practical deployment in systems with constrained power budgets, while preserving the familiar behavior of the host surface during normal use.

TCS is also designed to support disciplined physiological signals suitable for real-time use in interactive systems.

• managing slow drift associated with contact variation
• reducing ambient influence through illumination and sensing coordination
• suppressing motion-related disturbance through stability-aware gating

The purpose is architectural: keep the host interface clean and bounded, and avoid exporting uncontrolled surface-wide raw data.

TCS surfaces can expose a structured interface layer so the surface may be treated as a subsystem in broader platforms.

• synchronous streaming during contact sessions, where one or more suitable signals may be provided
• event-oriented summary outputs, where derived indicators can be reported at policy-defined intervals
• waveform-level access in controlled integration modes, bounded to admitted regions and disciplined channels rather than unconstrained surface-wide export

• region admission and deactivation controls
• evaluation or self-test requests appropriate to the integration context
• policy controls related to power and acquisition scheduling
• triggers for re-evaluation when conditions change

TCS is an architectural sensing layer that can apply across a range of applications and form factors. The topology is not locked to one object type or one physiological output.

Example embodiments include:

• a compact curved surface designed to instrument palm contact during interaction
• a work surface zone that supports physiological sensing during repeated contact events

The TCS architectural model can be understood as a system-level operating model expressed across several dimensions. From a sensing topology perspective, it moves from point-based acquisition toward distributed surface participation that is admitted locally based on interaction at the surface. In power posture, it shifts from persistent operation to a dormant- by-default approach with localized activation during interaction.

In activation logic, the model emphasizes event-driven admission and subset engagement rather than surface-wide continuous activity. In routing behavior, it supports adaptive selection among candidate sensing locations as conditions evolve, rather than relying on a fixed channel. At the system boundary, it favors disciplined export of bounded physiological channels over surface-wide raw data exposure. Finally, in integration posture, it treats the surface as a governed subsystem rather than a discrete sensor, with admission, evaluation, selection, and export coordinated under policy aligned to host platform needs.

TCS marks a shift in how surfaces can capture cardiovascular-related physiological information. Rather than relying on point-based sensing or user-managed placement, a surface can admit a region of interest during contact, evaluate candidate signals for suitability, and export a disciplined physiological stream aligned to host integration.

TCS transforms the surface from a passive boundary into a physiological interface embedded into the objects and environments people already touch.