Standard delivery service robots are mainly used for delivering coffee, meals, documents, experimental materials, medicines, and other items in cafes, restaurants, office buildings, hotels, laboratories, hospitals, etc. They can also be used for material handling in factory production lines. No need to lay QR codes, reflective boards, or magnetic strips in advance in the work environment, deployment is simple. The 280 degree open 3-layer tray is easy to operate, with a rounded outer contour design, flexible movement, safe obstacle avoidance, and adaptability to dynamic and complex scenarios with many people. It communicates with the elevator control module and can ride the elevator independently. Through the glass door and self charging, it can save manpower investment, reduce operating costs, enhance customer brand value, and improve service quality for customers.