The Emergency Department (ED) is a stressful, safety-critical environment, which is overcrowded, noisy, chaotic, and understaffed. The built environment plays a key role in patient outcomes, experiences, and the mental health of healthcare workers (HCWs). However, once a space is built it is difficult to change it; so the modularity and adaptability of new technologies such as robots could potentially help stakeholders mitigate some of these challenges; yet, there is a lack of research in this area, particularly in the ED. In this paper, we address this gap by engaging HCWs in a research-through-design process, utilizing design fiction, to envision a future resilient ED.  Here, robots scurry along the ceiling, provide help at the bedside, and smart furniture and walls provide spaces for privacy and calm. We co-created design prototypes of future intelligent systems that can modify the built environment to support resilience, which we then used to co-create a Design Catalog with HCWs, which contains a collection of future technology prototypes contextualized within the ED. We found that HCWs envisioned many ways for intelligent systems to help them reimagine the built environment, including ways to enhance HCW-patient communication, improve patient experience, support both HCW and patient safety, and use reconfigurable spaces to support privacy. We hope our work inspires further exploration into using new technologies to reimagine and reconfigure the built environment to support resilient hospitals. [PDF][Design Catalog]