Headlight Beam Pattern Evaluation Customer to Engineer to Customer - A Continuation

The method of communication between the customer and the engineer has been refined to further improve the headlight beam pattern development process. The refinements included: a) reduction of word pairs used for semantic differential scaling and b) use of shortened questionnaire on night-roadway viewing zones. The added benefit of the new questionnaire method allows the engineer to evaluate the customer responses of the beam pattern within specific areas on the road scene. A statistical technique called factor analysis has been used to evaluate and to reduce the large number of semantic differential word pairs used in the previous work by Jack, O'Day and Bhise (1). A comparison of the two questionnaire forms used in the evaluation surveys was completed based on an evaluation of beam patterns in a dynamic drive situation. In addition, weighting factors for night viewing zones on the road surface and for the reduced number of factor analyzed word pairs have been derived to aid in applying relative importance factors for areas of view and word pair topic. The present research suggests a strong relationship between the scores of the reduced word pair/zone questionnaire and the overall positive score of the longer (“short”) questionnaire used in this and the previous research.