Near the end of the prototyping stage , after engineers create actual working samples of the product they plan to produce , engineering verification testing ( evt ) uses prototypes to verify that the design meets pre - determined specifications and design goals 在原型階段結束時,工程師創建他們計劃完成的真實工作產品實例之后,工程驗證測試( evt )使用原型來驗證實際是否與之前決定的規范和設計目標一致。