As we all know that Six Sigma refers to a set of quality-control tools that businesses can use to eliminate defects and improve processes to help boost their profits.
I'm afraid that there is some misunderstanding. There are two methodologies in Six Sigma: DFSS (Design for Six Sigma) for R&D projects (i.e. for new products/processes/technologies) and DMAIC (Define/Measure/Analyze/Improve/Control) for Engineering/Manufacturing/QC/Maintenance projects (i.e. for existing products/processes/technologies improvement).
to design new products/processes, mechatronics design process includes modelling, simulation, prototyping and deployment related with R&D projects, and also DFSS.