Design in Biomedical Engineering: Student Applications of Design Heuristics as a Tool for Idea Generation

Creative concept generation is an important source of successful innovation; thus, techniques that support creative conceptual designs are imperative to instruction on engineering design processes. One ideation tool, Design Heuristics, was developed through empirical studies of designs by professional engineers and in award-winning products. While the Design Heuristics strategies were identified and validated in the product design space, their application in biomedical engineering spaces has not been examined. In our study, we implemented a Design Heuristics lesson during one session of a semester-long biomedical engineering design course for upper-level undergraduates. In this paper, we present an analysis of three design teams from the course to examine the applicability and impact of Design Heuristics within biomedical engineering design problems. Findings revealed that the biomedical engineering students successfully engaged in idea generation using Design Heuristics to build new biomedical engineering concepts. The findings suggest that Design Heuristics can support idea generation in biomedical engineering contexts, demonstrating the value of Design Heuristics outside of the previously-documented mechanical engineering and industrial design contexts. Introduction A primary goal of the undergraduate engineering curriculum is to support students’ development of design skills, demonstrated by the ABET requirement that students should be able to “design a system, component, or process to meet desired needs.” ABET also emphasizes that these solutions will need to be innovative to address the complex problems in the world today. Idea generation and development are important processes in design that lead to innovative outcomes and instruction using idea generation tools can increase the likelihood of students’ success in these processes. One idea generation tool, called Design Heuristics, has been shown to be beneficial to student solution processes and outcomes in engineering design courses. The focus of these studies has been on product design in mechanical and multi-disciplinary engineering and industrial design courses. However, there is potential for Design Heuristics to be applied to other engineering disciplines, such as biomedical engineering. Biomedical engineering design courses focus on medical devices, and incorporate a wide variety of expertise and engineering disciplines, including mechanical, electrical, and chemical engineering. The breadth of experience represented on a design team can help to generate innovative and diverse ideas. Biomedical engineering design courses focus on the processes of reverse engineering, problem definition and conceptualization, preliminary design, final design selection, prototyping, testing, and marketing, as well as addressing some unique biomedical focus areas such as medical device regulation. Within the field of biomedical engineering design, there has been limited discussion of how to instruct students about the idea generation process. Instruction on idea generation appears in some biomedical engineering design textbooks with an emphasis on mindset, collaboration, and versatility in idea generation, along with guidelines for facilitation. However, textbooks in biomedical engineering design provide minimal information about techniques for idea generation. Design Heuristics have been shown to be valuable in multiple product design contexts and biomedical engineering product design may also be a relevant application area. Biomedical engineering design includes device-oriented designs that require physical interactions with users, and so may benefit from generative heuristics gleaned from enduser products. In this research, we explored the extent to which biomedical engineering students were able to apply Design Heuristics during idea generation, and whether they selected Design Heuristics-driven concepts as practical concepts to take forward in their design projects. Background The consideration of multiple and diverse concepts during ideation can lead to innovative solutions. Research indicates that diverse idea generation is difficult for students, and that limited resources exist for engineering educators on how to generate innovative concepts. Common teaching methods for engineering idea generation include “brainstorming” and morphological analysis; however there is little formal idea generation instruction or systematic approaches to idea generation. Tools to facilitate idea generation include brainstorming, brainwriting, conceptual combination, Design Heuristics, IDEO Method Cards, lateral thinking, morphological analysis, Synectics, SCAMPER, and TRIZ. Each of these tools has a unique approach to guiding idea generation, varying in their focus specificity, and usability. For example, SCAMPER aids in idea generation by defining general prompts; Synectics provides general theme suggestions to define the contextual meaning of product, and brainstorming sets rules to guide a team during idea generation sessions. Design Heuristics provide “rules of thumb” to introduce variation in design based on analyses of past products. Because of the existing evidence of the applicability of Design Heuristics in product design contexts, we selected this tool for use in a biomedical engineering design course. Design Heuristics are idea generation strategies to prompt designers to explore a wide variety of ideas during idea generation, leading to more diverse and creative design concepts. Cognitive heuristics as defined in the field of psychology facilitate “best guesses” at potential solutions, and their use has been shown to support expert performance. They are heuristics rather than algorithms because they provide a suggestion towards a possible solution rather than a deterministic outcome. A specific set of 77 cognitive heuristics for product design, called Design Heuristics, have been identified in studies of expert and advanced product designers and analysis of innovative products. Each of the 77 Design Heuristics provides a different, specific prompt, and is illustrated with a graphic representation and examples of its use in specific products. The heuristics are printed on an index card that can be considered by designers to prompt ideas. On the front of each Design Heuristic card, there is a title of the strategy, a graphic image, and a description of the heuristic (Figure 1). The back of each card provides two example products where the heuristic is evident, demonstrating how the heuristic can be applied to multiple products. One of these example is always a seating device, and the other example is a consumer product, represented by a variety of products throughout the set of 77 cards. Figure 1. Design Heuristic card #50, Provide Sensory Feedback. (a) Front features the Design Heuristic strategy and description with image and text. (b) Back features two examples of how the heuristic can be applied. For example, the Design Heuristic, Provide sensory feedback, prompts the designer to consider how to provide feedback to the user when they interact with the product. For example, in designing a prosthetic, this Design Heuristic could be applied by adding vibrating sensations for the user whenever their prosthetic touches a surface. By pushing the designer to consider aspects of designs noted by other designers, Design Heuristics can help novice engineers broaden their conceptions of the design space, consider non-obvious ideas, and generate multiple, diverse concepts. In a series of studies, the Design Heuristics cards have been empirically validated as effective in helping students generate conceptual solutions to address design problems. Designs developed with the cards were non-obvious and distinct, and led to diverse and creative ideas in later stages of the design process. In studies with first-year mechanical engineering students, design concepts generated with Design Heuristics were more original than those generated without Design Heuristics, which were often replications of known ideas or simply minor changes to existing products. Another study engaged first-year engineering students by teaching Design Heuristics as (1) a concept generation technique and (2) a concept transformation technique. More variety of solution concepts was observed in design concepts generated with the Design Heuristics. In a study with upper-level engineering students working in teams, concepts generated using Design Heuristics were observed as more practical, and were maintained from initial ideation through the final project design. In this study of teams working on different design projects, Design Heuristics were found to be applicable across a diverse range of problems. In sum, Design Heuristics have been established as a beneficial tool to assist mechanical engineers in generating diverse and create ideas. In the present study, we sought to determine whether this instructional method would also benefit students in the domain of biomedical engineering design. Research Methods Research Questions The focus of this study was to investigate whether and how Design Heuristics may assist students in generating design ideas in the context of biomedical engineering problems. We were also interested in how students developed their initial ideas as they refined and developed their concepts. Our project was guided by the following research questions: How are Design Heuristics applied in concepts generated by biomedical engineering students? To what extent are heuristic-driven ideas present in concepts considered worthwhile and selected to take forward in the design processes? Course Context and Participants The goal of the biomedical engineering design course at a large Midwestern university was to design, test, and build medical devices for stakeholders such as university departments, clinicians, and industry. Skills developed through the course included problem definition, concept gener