Overview This activity demonstrates the process of balancing an assembly line, which is designing the same amount of work content, or time, at each workstation. Work that is done to build skateboards is simulated through video and animation, allowing students to experience the basic steps of the manufacturing, or assembly process. Students will learn how changing the work being done at each workstation, or changing the number of people working, can impact the flow of the assembly line and the utilization of each operator. Elementary Level Objectives: Define new vocabulary associated with assembly lines Compute utilization values and explain importance of high utilizations Fractions: reduce, compare, convert to percent Round decimals to given place value Brainstorm methods to increase utilization Middle School Level Objectives: All of the above objectives and Solve modeling problems using proportions High School Level Objectives: All of the above objectives and Compute percent change in operator utilization Solve modeling problems using linear equations and percent change Identify and explain the representation of slope in a cost equation Vocabulary: Assembly Line - A manufacturing process in which parts are added to a product in a specific order or sequence to create a finished product. Bottleneck - A circumstance where the performance of an entire system is limited by one workstation, typically the slowest workstation. The term bottleneck uses the metaphor of a bottle, where water is poured out of a bottle, and the rate of flow is limited by the width of the exit - that is, bottleneck. Manufacturing - The production of goods for use or sale using people, machines, and tools. Typically, materials are transformed into finished goods. Process Simulation - A model that is used for the design and analysis of a manufacturing process and shows the flow of parts or products. Throughput The rate at which products come off the line (parts per second or per minute) Unbalanced Assembly Line - Where the time taken to perform work at each workstation is not the same (some shorter, some longer), usually resulting in a build-up (bottleneck) at one of more workstations. Utilization - A measure of busy time. How busy a person is on the line relative to how much time they could be busy or working. Workstation - A particular stop on the assembly line where a specific task is performed. Page 1 of 5
Lesson Plan for All Levels: Supporting File Assembly Line Introduction 6 min Show PowerPoint Watch PowerPoint Assembly Line PowerPoint s Introduce Vocabulary Video: Overall view of TPS Lab Assembly Line Introduce Process Simulation Determine Utilization Times 2 min Introduce new words. Active participation Complete Part I in Student Worksheet 2 min Show Video Observe assembly line process 3 min Show Simulation Watch Simulation 5 min Open Data Workbook Decide whether students use data from first 6 min, first 1 hour or first 8 hours. Brainstorm 5 min Brainstorm changes that could be made to the assembly line to increase busy time and improve utilization at each station Show Simulation for Second Set of Data Second Set of Data and New Utilization Times Answer Question #1 in Part II Copy Base Case Operator Busy Times into Table 1 in Student Worksheet. Answer Question #2 in Part II Active Participation Answer Questions #3-5 in Part II 3 min Show Simulation Watch simulation 15 min Click tab at bottom of workbook to view Reallocating Tasks Data Direct students to use data from same time interval used in Table 1 Answer Question #1 in Part III Copy New Data into Table 2 Complete Table 2 in Part III of Student Worksheet Student Worksheet: Elementary Middle High Overview Video Base Case Simulation Data Workbook Reallocating Tasks Simulation Data Workbook Page 2 of 5
* The following plans involve questions from the Student Worksheet which could instead be assigned to students for independent practice outside of class. Discussions could occur afterwards. Elementary School Lesson Cont d: Utilizations and Draw Conclusions 4 min Direct students to complete Part IV then have group discussion Complete Part IV Questions #1-6 Middle School Lesson Cont d: Utilizations and 4 min Direct students to complete Part IV then have group discussion Complete Part IV Questions #1-6 Draw Conclusions Cost Analysis 3 min Ask class to identify variables of cost Answer #1 in Part V of Student Modeling Questions- Manufacturing Costs High School Lesson Cont d: Utilizations (See next page) 5 min Direct students to answer Questions #2-3 in Part V and discuss answers Worksheet Answer Questions #2-3 2 min Direct students to answer Questions #1-2 in Part IV then have group discussion Calculate Percent Change Complete Questions #1-2 in Part IV 4 min Review Percent Change Formula Copy data from Tables 1 and 2 into first two columns of Table 3 Calculate percent change for each operator Answer Questions #4-7 in Part IV Draw Conclusions 2 min Direct students to answer Questions #4-7 in Part IV then have group discussion Modeling Questions- 4 min Direct students to answer Questions #1- Utilization and 2 in Part V then discuss answers Labor Costs Cost Analysis 2 min Ask class to identify variables of cost (See next page) Modeling Questions- 5 min Direct students to answer Question #4 in Manufacturing Costs Part V and discuss answers Complete Part V Questions #1-2 Answer Question #3 in Part V Students answer Question #4 Page 3 of 5
Cost Analysis using an Equation or Relation What are the costs of running the skateboard manufacturing company? - Materials (Variable) - Factory Building and Utilities (Fixed) - Equipment (Fixed) - Labor costs = Hours Wage x Number of Hours worked (H) Page 4 of 5
Ideas for Hands-on Assembly Line Activities Create an Assembly Line in the classroom using one of the following ideas: Bead Bracelets S mores Lego Buildings Paper Airplane Burgers -Using paper and markers for the buns, meat, and condiments Create one or more assembly line(s) with teams of 2 at each station an operator and a timer. There should be a head timer assigned to the entire line who starts his/her clock when production begins (when assembly begins at Station 1) and announces to all timers and operators when production is Complete. This will provide the Total Time for every station. Complete is a set amount of time determined by the teacher or when a certain number of products have been completely manufactured. At each station there should be a written task for the assigned operator. The timer starts the clock at the beginning of production for the line, but stops it whenever operator is idle, and restarts it when the operator begins the task again. All timers stop their clocks when the head timer announces time is up. Utilization of each operator is calculated by each operator and timer at their assigned station. (Utilization = Busy Time/Total Time) Data is shared and ideas are brainstormed about how to make a more balanced line and have better operator utilizations. Agree on one or more changes to make and run the line again to compare utilizations. Notes: To produce less desirable utilizations and an unbalanced line for the first run, use a dry assembly line and assign tasks at each station that have variable completion times mix up beads/legos to make them difficult to find, have S mores ingredients in unopened/sealed packages, require some burger pieces to be cut out of the paper, etc. Or have one station have multiple tasks and others just one simple task. Also instruct each operator not to begin a task until the part has arrived from the previous station. (Do not open packages or begin cutting pieces.) One idea for better utilizations and a more balanced line in the second run is using a wet assembly line. This means that for each station, a model should be created already so they can simply add their part, not wait for the work of the first person to make its way to their station on the assembly line. Other ideas could be organizing the materials at each station, having the packages already opened ahead of time, having burger pieces precut, adding an operator or an additional station to the line where there are many tasks to complete, etc. You can choose to have operators and timers switch their roles for the second run, but have the students take that into consideration when comparing data. (Each worker s efficiency will be different.) Page 5 of 5