Influence of modularity on delivery dependability: analysis in a bus manufacturer

Abstract

One of the benefits of modularity in manufacturing is the reduction in time for completion of orders. Although the literature exploits such benefits theoretically, there is a lack of empirical evidence to support it. The purpose of this study is to provide such evidence of the cause-effect relationship between modularity and reduction in completion time for the orders received by a bus manufacturer. The study considers three types of time involved in the completion of orders: corporate time (T1), project time (T2), and production time (T3). The evaluation examined 140 orders (70 with modularity, 70 without). The CausalImpact technique is used to investigate causality relationships between interventions and manifest variables (e.g. modularity and time took to complete manufacturing orders). The T1 underwent an absolute reduction of 8.46 days in 17.73 days, which is a relative reduction of 47.71%. The T2 experienced an absolute reduction of 13.72 days in 25.11 days, which is a relative reduction of 54.64%. In T3 there was an absolute reduction of 8.33 days in 27.18 days, which is a relative reduction of 30.65%. The likelihood of the three cause-effect relationships exceeded 99%. The main contribution of this paper is testing the relationship between the adoption of modularity and the reduction in the variables that compose delivery time, as claimed by the literature.