Estimating a Process Control Model of Vehicle Front Wheel Alignment: A Case Study in Off-Line Experimentation

An off-line experiment was performed to estimate a model for on-line process control which describes the empirical relationship between the design and production factors affecting the front wheel camber angle. It is shown through a case study that models for process control estimated from off-line experiments may not generate online minimal variance predictions for vehicles representative of those produced in the assembly plant. This occurred in a case study experiment because a characteristic of the vehicle used in the experiment was identified which could not be manipulated or controlled during experimentation. It is shown that the developed methodology for augmenting the experiment would improve the model for on-line process control by generating minimal variance predictions for vehicles more representative of those produced in the assembly plant.