top of page


Digital Human-in-the-Loop

The digital human-in-the-loop (D-HIL) is a novel early-phase design framework that supports human-system integration and enables designers to align design objectives toward people-planet well-being.

Injecting Human Factors into Early-Phase Design 

Although computational design tools, such as generative design (GD), have paved the way for products with improved mechanical performance (e.g., improving fuel efficiency by reducing part weight), many fall short of considering human factors, isolating HFE principles from early design activities.

The D-HIL design framework injects human factors engineering principles into the computational or virtual environment via digital human modeling (DHM) research. Experimental- and simulation-based DHM strategies, along with emerging technologies (e.g., virtual reality, motion capture), help facilitate the prediction of human well-being and overall system performance early in the design process. 

Digital Human Modeling 

Within the D-HIL framework, conceptual design ideas iteratively modified through DHM and computer-aided engineering (CAE) in a parallel sequence - before ever getting into the prototyping phase. This way, human needs, abilities, and limitations are considered early in the design process. Design errors or human-product incompatibilities can be captured before prototyping begins.

Data related to human attributes can come from experimental or computational methods. For example, human posture data can come from either a manual anthropometric setup or various digital systems (motion capture, eye-tracker, a motion prediction model). If manual methods are used, descriptive task parameters (e.g., push-pull distance, lift-lower height) are inserted manually to generate ergonomics evaluations. The CAE model can be updated parametrically, depending on the changes required after each ergonomic and structural assessment. The effects of variations on the CAE model in terms of ergonomics and structural integrity can be cross-checked simultaneously.

D-HIL framework applied to the conceptual design of a hospital cart

D-HIL design framework applied to the conceptual design of a hospital crash cart. 

Human Factors Design Content
  • The D-HIL design framework enables designers to proactively visualize, evaluate, and optimize designs in a computer or virtual environment using DHM.

  • Injecting human factors early via DHM reduces the number of design changes and corrections, thus positively impacting the overall development cost. 

  • D-HIL concentrates on human factors design content/knowledge, which comprises scientific and creative methods for modern human-centered design.

Human factors design concent

Human factors design content scientific and creative methods for modern human-centered design.  

Data Integration
  • Using DHM as the backbone, the D-HIL design framework fuses three types of input: (1) Human, (2) Environment, and (3) Simulation data.

  • The above data integration allows designers to explore human-product interaction and performance in different “what-if” scenarios computationally.

D-HIL design framework

D-HIL design framework integrates human, design, and systems knowledge. 

bottom of page