Naval Surface Warfare Center Philadelphia Division, Pa –
During the latest installment of virtual Lunch and Learn sessions, Naval Surface Warfare Center, Philadelphia Division (NSWCPD) Chief Engineer (CHENG) Scott Freedner welcomed the Naval Post Graduate School (NPS)’s Michael O’Neil, who spoke about Human System Integration (HSI) on July 15, 2021.
NPS describes HSI as follows: “HSI acknowledges that the human is a critical component in any complex system. It is an interdisciplinary approach that makes explicit the underlying tradeoffs across the HSI domains, facilitating optimization of total system performance in both materiel and non-materiel solutions to address the capability needs of organizations.”
After a brief introduction by Freedner, O’Neil explained the integral role HSI plays in combining humans and technology in the design of an application. Drawing upon materials from the NPS’s HSI program, O’Neil introduced and explained HSI concepts to the audience, and shared examples within military platforms.
“Both humans and technology have contributions they can make to a given system, but each has limitations as well. In the best case, the strengths of one party offset the weaknesses of the other,” explained O’Neil. “The end state we’re looking for in the acquisition process is to close functional gaps between humans and technology that could affect performance and safety. If we’ve done our work well, we will have a system where both parties work in harmony.”
HSI tries to achieve this by focusing on an essential question: What tradeoff decisions are being made in the design process relative to humans, and do they get us the results we want in the end?
O’Neil highlighted the challenges of incorporating HSI in some recent examples:
“On vehicles designed to protect soldiers from roadside bombs, a lot of time was spent on engineering passenger seats to mitigate the shockwave from an explosive blast,” said O’Neil. “But if the seats are not designed to comfortably accommodate soldiers of different sizes dressed in full battle kit, then we can end up losing the blast mitigating effects we are seeking … or worse, the seats won’t be used.”
He continued, “Another tradeoff of making blast-resistant vehicles is that there typically aren’t many entries and exits, which can be useful for blast resistance, but can inhibit the crew’s ability to exit the vehicle quickly if attacked. When the vehicle is hit with an IED, the occupants may survive the blast, but these vehicles often roll over, and passengers may be trapped and unable to escape.”
O’Neil highlighted the development of the F119 engine (used in the USAF F-22) as a successful implementation of HSI. The vendor in this case heavily prioritized gathering input from Department of Defense (DoD) maintainers on the developing design and then incorporating this feedback to help make tradeoffs in the design process. They invested millions in building a full-scale mockup very early in the design, which gave them unique insight on how to make maintenance more efficient. Access to common maintenance components was improved, unnecessary steps were reduced or eliminated, and the variety of tools needed for maintenance was reduced. These efficiencies in turn reduced the manpower required for maintenance. In the end, the engine was selected over an alternative with higher thrust rating because of its edge in maintainability and potential for life-cycle savings.
“The true power of HSI is that if it’s done early, it can have a tremendous effect on shaping a more effective, efficient and safe system,” noted O’Neil. “That’s what the warfighter deserves: the best system we can give them.”
After his presentation, O’Neil answered numerous questions from the audience about HSI historical and future breakthroughs, the difference between systems engineering and HSI, and how to consider human variability when selecting test audiences.
Freedner added that, “HSI is a competency we are looking to develop in Philadelphia in the near future and make it a part of everything we do.”
More details on the HSI program at NPS are available at [https://nps.edu/web/dl/cert_hsi].