This study aims to understand the effect of additive manufacturing (AM) on design fixation. Whereas previous research illustrates the positive aspects of AM, the overarching hypothesis of this work is that it might also have negative effects with respect to conventional manufacturability. In this work, participants from two groups, a design for conventional manufacturing (DfCM) group, and a design for additive manufacturing (DfAM) group, were asked to design a basic product. Then, a second iteration of the design asked both groups to design for conventional processes, and to include subtractive and formative methods like machining and casting, respectively. Findings showed that the DfAM fixated on nonproducible manufacturing features and produced harder to conventionally manufacture designs, even when told specifically to DfCM. There was also evidence that the complex designs of the DfAM group limited their modeling success and seemed to encourage them to violate more design constraints. This study draws attention to the negative effect of AM knowledge on designers and provides motivation for treatment methods. This is important if AM is used in prototyping or short run production of parts that are slated for conventional manufacturing later. The issue of design fixation is not a problem if AM is the final manufacturing method—a more common practice nowadays. This work suggests that one should consider the possibility of fixation in design environments where AM precedes larger volume conventional manufacturing.

This study assessed the effectiveness of three-dimensional (3D) visual feedback from design for manufacturability (DFM) software on mitigating design fixation on nonproducible manufacturability features. A fixation group and a defixation group were asked to design a basic product for additive manufacturing (AM) and then to modify the next iteration for conventional machining. The fixation group relied on their self-assessment while modifying, while the defixation group utilized dfm software feedback. Results showed that 3D feedback reduced design fixation on nonproducible features and improved the machinability of modified designs. Findings suggest the use of dfm software for treating the design fixation related to AM and for facilitating migration of designs from additive to conventional manufacturing. This work could be applied to manufacturing industries, particularly where AM is used for prototyping, or when demand for part changes and an AM part needs to migrate to conventional methods.

Periodic intraoperative microbreaks with calesthenic exercises performed within the sterile field improved self-reported mental focus (38%) and physical performance (57%) for 56 surgeons. Therefore, targeted stretching exercises and a web-application (web-app) leading the stretches with a reminder system were developed and piloted using user-centered design principles. A focus group with 10 users was conducted to refine the developed app. Seven surgeons (4 females) at a quaternary medical institute piloted the periodic stretching web-app in their operating rooms. At the end of each surgical day, the surgeons completed a short survey about the intraoperative stretching exercises web-app impact on their physical performance, mental focus and workflow disruption. Non-Routine Events were captured during the procedures. Twelve surgical days were followed with a median of 6 microbreaks/day/surgeon. Results showed that better physical performance and lower fatigue were reported (91.7%) across the surgical days, also better mental focus was reported (83.3%) across the surgical days, and less pain/discomfort was reported (100%) across the surgical days, with others reporting no change. The web-app leading sterile field microbreak stretches helped reduce physical pain, discomfort/pain, fatigue, and improve mental focus with minimal disruption for a small sample. The web-app is a promising tool for improving surgeon mental focus and physical performance and potentially musculoskeletal health.

Do physical and psychosocial stressors interact to increase stress in ways not explainable by the stressors alone? A preliminary study compared participants' stress response while subjected to a physical stressor (reduced or full physical load) and a predetermined social stressor (confronted by calm or aggressive behavior). Salivary cortisol samples measured endocrine stress. Heart rate variability (HRV) and electrodermal activity (EDA) measured autonomic stress. Perceived stress was measured via discomfort and stress state surveys. Participants with a heavier load reported increased distress and discomfort. Encountering an aggressive individual increased endocrine stress, distress levels, and perceived discomfort. Higher autonomic stress and discomfort were found in participants with heavier physical load and aggressive individuals. The results suggest a relationship where physical load increases the stressfulness of aggressive behavior in ways not explainable by the effects of the stressors alone. Future research is needed to confirm this investigation's findings.