Josh Liddy

Support Scientist, Center for Human Health and Performance

Current Research

My research centers on head-mounted systems for dismounted soldiers. Over the past 40 years, combat helmets have evolved from single-purpose protective shells into adaptive, multifunctional platforms that can mount advanced technology while providing enhanced protection against modern threats. However, head-mounted systems can increase injury risk and degrade operational performance—broadly defined here as the ability to maintain situational awareness, respond to threats, and move effectively while managing physical and cognitive demands. Head-supported mass induces shifts in mechanical variables, such as the center of mass and mass moment, which affect head stability and movement, both of which are critical for active vision. Part of my research aims to identify and evaluate the impacts of head-supported mass on dismounted soldiers’ ability to move, perceive, and respond to goal-relevant visual information. 

Another emerging problem for dismounted soldiers is head-mounted displays (HMDs). A major concern is the strain placed on resource-limited capacities like perception, attention, and cognition. While these technologies purport to enhance operational capabilities by integrating optics, environmental sensors, and other functionalities, the tradeoffs induced by such systems remain poorly understood. My research seeks to clarify these impacts by investigating how HMDs influence situational awareness, information processing, and responsiveness in dynamic, task-relevant environments. Findings from this work will contribute to design guidelines for HMDs

Research Interests

My research interests align closely with the new thrust on the ethics of technology and accountable, human-centered design, specifically in the evaluation and translation of health monitoring technologies to serve the public interest. I'm particularly drawn to the emphasis on interdisciplinary, community-driven collaborations, which resonate with my own commitment to research that prioritizes the needs and experiences of end-users. By leveraging insights into how head-mounted technologies impact operational performance in dismounted soldiers, my work aims to inform the design and evaluation of systems that are both ethically responsible and highly functional in real-world settings. 

In collaboration with the Public Interest Technology initiative, the Center for Nursing and Engineering Innovation, and other affiliated centers, I look forward to contributing to the development of technologies that not only enhance individual health outcomes but also promote equitable access and community engagement. I see tremendous potential in applying human-centered design principles to ensure these technologies are not only effective but also respectful of users’ autonomy and well-being, especially within aging care and other sensitive health domains.

Academic Background

• BS Kinesiology, UMass Amherst, 2012 
• MS Health and Kinesiology, Purdue University, 2014 
• PhD Health and Kinesiology, Purdue University, 2020 
• Postdoc in Cognitive, Linguistic, and Psychological Sciences, Brown University, 2020-2022 
• Postdoc in Kinesiology, UMass Amherst, 2022-2024