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I’m developing a physical product that requires many parts and is about as complex as, say, a robot vacuum or the litter robot. I have experience in e-commerce and marketing, and creating custom goods and innovating products with suppliers in China etc. But most of my experience in product development is at the level of making small changes to existing products, softgoods, light 3D design work etc. I’m currently working on a new product that is far more complex than anything I’ve tackled before. I’m building prototypes and 3D printing parts, working with CNC shops to proof out certain aspects but I’m having trouble finding good resources on tackling a project like this full on. It’ll be the first time I need external funding most likely. First time working with engineering firms. First dealing with so many suppliers/parts/materials and dealing with assembly. Anyone have any recs for me in the world of complex product design and launch? Or a book?