I need a design for a new insulin pen and cartridge platform. The focus should be on usability, specifically on simple cartridge replacement. Key Requirements: - Ergonomic design for comfortable handling - Aesthetic appeal - Usability with a focus on simple cartridge replacement Ideal Skills and Experience: - Experience in medical device design - Strong background in ergonomics and usability testing - Proficiency in 3D modeling and design software - Knowledge of safety standards for medical devices