The quality loss function
, as well as the additional Taguchi methods, solves in a way the conflict between "high quality" and "low manufacturing costs", offering an engineering tool to exactly define the product quality during the development phase of a product.
Purpose of this work is to extend the STS optimization method to minimize manufacturing cost with quality loss function
in a continuous cost function to achieve near optimal tolerance allocation using total cost minimization as the criteria.
Taguchi has proposed as Quality Loss Function a quadratic equation described by the relation 1 (Fowlkes & Creveling, 1995):
By utilisation of the Taguchi's Quality Loss Function it can be quantified simultaneous the process's technological performances and his costs, too.
and Ghun, Y.H., "Effect of quality loss functions
on the economic design of X process control charts", European Journal of Operational Research, Vol.
Quality Loss Function
for confirmation experiment 3 shows that for a target value of 25 mm, a tolerance of [+ or -] 0.5 mm, k = 160 and a scrap cost of 40$/unit of product, the loss before experiment was 9.56 $/unit of product and after the experiment the loss decresed significantly to 3 $/unit of product.
The standard by which these quality-related design factors are studied and weighed is based on one of the major principles of Taguchi's approach - the quality loss function
, a notion that differs from the conventional concept of quality.