They may operate autonomously or collaboratively with humans, adapting their actions based on the data they collect. A key requirement for the M3X program is that these systems must function within a physics-based environment, whether physical or virtual, where interactions exhibit recognizable physical behaviors, such as those associated with gravity, friction, force, and inertia. Intelligent engineered systems are becoming increasingly integrated into our daily lives, interacting with humans across diverse environments and through different modalities (for example, visual, haptic, auditory). M3X aims to deepen the understanding of such interactions, particularly in complex and dynamic settings such as elder care, disaster response, and dynamic workplaces. The program encourages explorations into the physical or cognitive principles that enable or constrain human-machine collaboration, advancing foundational theories, interaction modeling, and technological innovations that enhance adaptability, efficiency, and intuitiveness. Proposals submitted to the M3X program must clearly articulate how the proposed work advances knowledge of bidirectional interactions between humans and intelligent engineered systems. Examples include robots assisting in disaster response, smart environments that learn user preferences, and virtual reality-based rehabilitation technologies that simulate plausible physics. While proposals are not required to address all aspects of the interaction, they must propose significant contributions to at least one of the following areas:

• Conceptual Frameworks and Theoretical Modeling
  Development of new conceptual, mathematical, or computational frameworks that provide structured approaches to understanding and analyzing the bidirectional interaction between humans and engineered systems. These frameworks serve as formalized models or methodologies that guide research in areas such as cognition, perception, and behavior of both humans and intelligent engineered systems during their interactions. Additionally, these computational frameworks facilitate the modeling of safe operating conditions in dynamic task environments and the identification of theoretical limits of cognitive and physical performance capabilities during interaction.

• Dynamic Interaction Analysis and Simulation
  Investigation of emerging and established bidirectional interaction phenomena in physical, virtual, or hybrid environments. Potential topics may include learning, co-adaptation, cooperation, competition, and multi-scale interaction. The program also welcomes novel experimental paradigms to evaluate processes and performance.

• Innovative Technologies for Enhanced Interaction
  Development of methods, tools, and technologies to enable novel or improved forms of bidirectional interaction, guided by hypotheses and interaction-driven requirements. Potential topics may include creating meaningful task environments (physical, virtual, or hybrid); designing new modalities and interfaces for interaction; developing advanced evaluation, measurement, and instrumentation methods; testbeds, and improving real-time integration of multi-modal sensorimotor data.

The M3X program strongly encourages proposals that aim to establish new perspectives and paradigms across one or more of the three areas listed above. To ensure strong alignment with M3X objectives, Principal Investigators are encouraged to submit a one-page Project Summary to M3X@nsf.gov for feedback from Program Directors.