An automatic machinery designer requires a diverse range of knowledge and skills, including:

1. Mechanical Engineering: Knowledge of mechanical engineering is essential for designing the physical components of the machinery, such as motors, gears, and moving parts.
2. Electrical Engineering: Knowledge of electrical engineering is required for designing the electronic systems that control the machinery, such as sensors, controllers, and power supplies.
3. Software Development: Knowledge of software development is necessary to control and automate the machinery. This includes programming the control systems, designing the user interface, and integrating the software with the electronic systems.
4. Robotics: Knowledge of robotics is important for designing and programming the machinery to perform complex tasks, such as sensing and manipulating objects.
5. Materials Science: Knowledge of materials science is necessary for selecting the appropriate materials for the machinery components, taking into account factors such as strength, durability, and weight.
6. Manufacturing: Knowledge of manufacturing is required to build the machinery, including expertise in welding, machining, and assembly.
7. Safety Engineering: Knowledge of safety engineering is critical for ensuring the safety of the machinery, identifying potential hazards, and designing appropriate safety features.
8. Project Management: Knowledge of project management is necessary to coordinate and oversee the various aspects of the machinery development process, from conceptualization to installation and maintenance.

Overall, an automatic machinery designer must have a multidisciplinary approach, with expertise in various fields, to ensure the machinery is designed and built to the highest standards of quality and reliability.