Final answer:
Project planners typically develop the broad project definition and scope during the concept phase, which is followed by the detailed design phase involving prototyping and refinement.
Step-by-step explanation:
Project planners develop a broad definition of what the project is and what its scope will be during the concept phase. During this phase, the team works on defining the problem, identifying the needs of potential customers, and establishing the constraints such as government regulations, available resources, and technology limitations. This is crucial for a clear understanding of the project's scope. Following this phase, the project moves into the detailed design phase where the architecture of the design is developed, including materials, processes, and component selection. This phase may involve multiple iterations of prototyping, testing, and refinement to ensure the final design properly aligns with the project's goals.