30.4 Paper Helicopters
Following the idea presented in the paper by George Box, ‘Teaching Engineers Experimental Design with a Paper Helicopter’, Quality Engineering 4(3) (1992), it is possible to construct a paper helicopter following the scheme in the figure below. Dropping it from a certain height, it first falls down in an irregular way, but when it opens the wings, it starts to rotate around itself falling down slowly.
To improve the design with the aim to maximize the flying time, a 28-4 factorial design is carried out with the following factors and levels:
To write the design matrix, the generators provided by Minitab were used, and the flying times (in seconds), in standard order, were:
The objective is drawing conclusions from the experiments performed, and suggesting which should be the next experiments to be carried out.
To create the design go to: Stat > DOE > Factorial > Create Factorial Design
We have 8 factors and choose a 28-4 design. Proceed to disable the option to randomize runs and, for the analysis, choose the graph of the effects in normal probability plot.
Introduce the results and analyze the data: Stat > DOE > Factorial > Analyze Factorial ...