To design an unmanned aerial vehicle, whether it is from the palm size to several tons, the design process comes first. A good process can improve efficiency. If not, there will be endless work.
There are three common industrial design processes: serial design, parallel design, and iterative design. In addition, stage jumps are common for drones, breaking all laws.
Simple products generally use serial design processes. It is very simple. Do one thing first and then another. The aircraft is designed after all. This is the easiest method for small teams to master and has a wide range of applications. . Its biggest advantages are less rework, fewer crossover issues, low management costs, and easy outsourcing. The disadvantage is low efficiency and long cycle.
Therefore, the more complicated design process, after having multiple professional departments or individual work, generally adopts parallel design. That is, everyone agrees on the interface in advance, and then they do their own things, without delaying each other, and finally work together to deal with cross-cutting issues. The biggest advantage of parallel design is high efficiency. The disadvantage of is that the management cost is quite high, the cross-cutting problem is very complicated. If an interface is not fixed, everyone will rework .
And for aircraft design, the most common method is the iterative design process, that is, the overall task is issued. Everyone has done everything that needs to be done, and they will modify the tasks and send it back according to overall statistics. Do it one more time. . . Until everyone is satisfied, then enter the next stage. Due to repeated modifications, the advantage is that it is suitable for aircraft, which has great uncertainty, but also has demanding performance requirements. The overall ability requirements are relatively moderate, but the work cycle is extremely long.
Why does the aircraft design use an iterative trial design process? Because the performance of the aircraft is related to the unstable air. Everyone has heard of the butterfly effect. It mainly refers to the uncertainty of the atmosphere. Also, the energy conversion efficiency of the propeller is uncertain, or even impossible to estimate. You can try to find a bamboo dragonfly and see if you can fly out the same height and the same direction twice. I call this “bamboo dragonfly effect”. Besides, aircraft is very sensitive to weight, but many weight estimations are often inaccurate, screws, cables, etc. With the large-scale application of composite materials, its weight estimation is very inaccurate. A 5% weight change not only causes changes in aircraft performance, but also changes in control parameters. You find that the aircraft looks the same, but flies completely differently. Therefore, the scientific method of aircraft design is to “try over and over again”, try to change the test until you are satisfied. This is iterative design.
To design the aircraft, it is impossible to completely distinguish what design process is actually going on. It probably uses “phase iteration, parallel design, serial design, “. There is also a key jump, that is when it is unsuccessful, we all go back and return to the previous state together. The airplanes are never finished because they don’t know the timing of the jump!
