Abstract
Field: Robot safety systems; hardware compatibility standards; AI robot architecture
Problem Solved: Existing robot safety systems treat safety as a passive hardware state — a switch, a boundary, a stop condition. No prior standard defines safety as an actively and continuously re-verified, machine-readable broadcast layer integrated into a hardware compatibility stack. In multi-robot and human-adjacent environments, passive safety is insufficient: a robot that has not actively affirmed its safety state in the last 100 milliseconds cannot be trusted to be safe.
Disclosure Summary: Safety Affirmity™ is Layer 4 of the RPnP™ seven-layer compatibility stack. It defines an affirmative, continuously re-verified safety state architecture in which every RPnP™-compliant robot broadcasts a verified Safety Affirmity Protocol packet at minimum 10Hz as a mandatory, machine-readable attestation of its current safety state. Safety is not a feature that may be switched on. It is an attested layer that must be continuously proven.
Key Technical Details:
• Safety Affirmity Protocol packet: 45 bytes, broadcast at minimum 10Hz
• Dedicated hardware line: pin 22 (Type-A) and pins 35–36 (Type-B) carry SAP signal on isolated lines independent of data bus
• Safety classes A, B, and C define escalating broadcast frequency and state granularity
• Safety Class C requires 20Hz minimum broadcast frequency
• E-stop callback must execute within 50 milliseconds
• rpnp_sap_start(), rpnp_sap_update(), and rpnp_estop_register_callback() are normative HAL API functions
• Hardware E-stop line is active LOW, pulled high, isolated ground on dedicated pins 31–34 (Type-B)
Prior Art Differentiation: IEC 61508 and ISO 10218 define functional safety requirements but do not define a continuous active broadcast protocol integrated into a hardware compatibility layer. No prior standard defines safety as a mandatory, timed, machine-readable broadcast that is part of a plug-and-play compatibility stack.
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.
Recommended Citation
Wang, Edward D. H., "Safety Affirmity™ Protocol — Continuous Active Safety State Broadcast for AI Robots", Technical Disclosure Commons, ()
https://www.tdcommons.org/dpubs_series/10480