CHAPTER 1: INTRODUCTIONAssembly lines are production processes of great importance in the industrial production of high quantities and also low volumes of customized products. In an assembly line, two or more different tasks are assembled sequentially to form a new finished product. An assembly line is a flow-oriented production system, in which operations on parts are performed at designed stations. Parts are moved along in-line stations usually by some type of conveyor system, such as a conveyor belt, transfer lines, or cranes. Henry Ford, the founder of the Ford Motor Company, is the father of modern assembly lines by introducing the use of assembly lines. This revolutionary assembly line served for the mass production of the Model-T automobile in 1908-1915 (Uddin et al., 2011). Assembly lines were basically introduced and designed for economically efficient mass production of standardized products, also taking advantage of high labor specialization. In the modern production system, however, the requirements of the product and its production systems have changed dramatically, mainly due to customer needs. Manufacturing companies must enable individualization of their products, develop more complex production strategies and assembly systems (Uddin et al., 2011). Designing and configuring assembly lines in the modern era requires high capital investment, so it has attracted the attention of researchers, to solve the problem of assembly lines and optimize their efficiency in terms of productivity and costs (Boysen et al. , 2006). StudyThere are many types of assembly lines designed and implemented in modern manufacturing. The blueprints of… middle of the paper… final assembly line and final inspection (Figure 3.2). The final assembly line of the commercial vehicle section is typically divided into two separate lines: 1) cab preparation line, 2) chassis assembly line. This project focuses only on the level of balance in the cabin trim line. Figure 3.2: Main departments in "Model MF" truck productions.3.2.1 Process flow and layout of the cab finishing line The following figure shows the detailed processes for the "Model" MF' cab finishing line. The layout designed for this line is the type of inline layout for a single model. The total labor used to assemble the parts and make the work items on the workstation is 10. This project does not consider other labor and processes other than T1 to T9, inspections or subassemblies. Sub-assemblies are performed off-line to reduce the total work time on the cab upholstery assembly line.