Engineering design process refers to the entire process of planning, creating, and improving with technical basis for an engineering project. It is an important link in the life cycle of a project, determining whether the engineering design and its development is reasonable or not.
In this section, we will introduce the 3 design phases that engineering designers usually go through:
- Conceptual Design Phase
- Preliminary Design Phase
- Detailed Design Phase
However, the process is not always linear; engineers often loop back to previous stages based on test results and feedback. This figure below features the loop of a general idea of a workflow:
- Conceptual Design:
Conceptual design is a process of continuous evolution from vague to clear, from abstract to concrete, mainly responsible for the initial design of the UAV’s overall structure. At this stage, everyone in the design team should think about the problem they are solving and share their opinions. The team should collect data, considering their ideas from multiple angles, and finally conclude several solutions. But many options might not be feasible, the team should check the existed data they collected and rule out unscientific solutions. Then, analyze the advantages and disadvantages of the schemes, evaluate their safety, economy, and other factors, and select the best scheme, which would be the main structure of the aircraft. The members also should have an understanding of the entire aircraft design process and preliminarily determine the part they are responsible for.
For the precise process of the Conceptual Design Phase, please click “Technical Design > Conceptual Structure & Analysis”.
- Preliminary Design:
Preliminary design is the prerequisite of the achievement. Generally, the designs before finalization are collectively referred to as preliminary design. At this stage, the team should drill down and refine the scheme they selected from the conceptual design phase: more data should be calculated, including the precise data of the wing (rotors), fuselage, empennage (tail), and so on. In addition, the airborne equipment of the aircraft should be selected roughly, including the main payloads to make sure the fuselage is appropriate to contain all necessities. Then, preliminary 3D modeling should be carried out.
For more information about “Calculation in Structure” and “3D modeling” can be found in list “Technical Design”.
- Detailed Design:
At this stage, all precise data of the aircraft and its systems should be determined and optimized. Airfoil of the wings and tail should be selected after simulation and comparison, anhedral angle of the wings should be calculated, and engines (motors) selected; the precise 3D model should be finished and used for precise whole-UAV simulation in professional wind tunnel tests in software like ANSYS Fluent. Some errors might occur, and some parts of the UAV might need to be improved (reselected). Other details should also be determined, such as winglets, ailerons, rudders, landing gears, and avionics equipment according to the scenario of the UAV. Then, the internal layout should be modeled, considering the weight and balance of the whole aircraft. Finally, an engineering notebook should be written, recording the whole developing process of the UAV.
Detailed instructions of each part can be found in the list “Technical Design”.
UAV Design Training 