Theory: Important… but insufficient.
We academics love theory and feel an obligation to deliver the principles of any topic in a compelling way. I teach Lean Operations, Supply Chain, and Product Development at Kettering University in Southeast Michigan. After 20 years in industry, I began teaching the way I was taught: by carefully crafting engaging lectures with examples intended to deliver the material in a way that transfers learning. For my first few terms, after completing instruction in class and inviting questions I heard… crickets.
I needed to make a change. There was a lot of teaching going on, but not a lot of learning. So I reflected on the best instructors of my industrial career. The most powerful lessons, the ones I remembered, were the ones where I experienced the learning principle through an activity. No wonder I was having difficulty. I’ve now come to appreciate that you can’t learn Lean by talking about it; you just need to do it.
Practicing Principles through Quick Cadence Simulations
Over time I’ve found that one of the most powerful and enjoyable methods of teaching is the hands-on simulation. This places the learner in an operational setting so he/she can practice the principle presented in the theory. These are simple activities, which often don’t involve computers.
Simulations are particularly helpful because Lean is such a different way of thinking that explaining it is not convincing. Few learners get it. Compound this with the contradiction of Lean to traditional production and management methods and it is difficult for students to accept one versus the other. Explain Kanban, for example, and people just don’t believe it’s better than computer scheduling backed by a warehouse of inventory. To really understand Kanban, you need to do it. Students who complete a simulation have a visceral feel for the principle. So much so that I often joke to my students that they will quickly forget the information delivered in the course, but they will remember the simulation forever. The power of a simulation is to give students enough confidence to apply the principle in their workplace.
This matters even more because Lean practice in the real world is important at Kettering. We are fortunate to have 600+ co-op partner employers. Our students work every other quarter at their co-op employer as a curriculum requirement of every degree program. We have a concentration of lean enterprises in the region, and our legacy is in the automotive industry as the former General Motors Institute. At least half of my students are exposed to Lean in their co-op work.
How to Design a Good Simulation
A big challenge of training is that there is never enough time. Using rapid learning cycles in a simulation has several benefits. The obvious one is that your total time for the exercise is less. Rapid learning cycles also allow for more experience with the skill. A quick cadence keeps student attention. Plus, students don’t have time to game the exercise; they simply focus on doing the task well.
Anything that does not contribute to the learning exercise of students making decisions and taking action, is waste. To eliminate waste, remove complexity, cost, or activity that does not add value. Materials can be costly so design the simulation using simple, cheap materials like tape, cards, paper, cups, and other craft items. Calculations take time from the exercise. Find a way to automate them by using a spreadsheet prepared for the task. As much as I appreciate hand drawn VSM or written A3, a template with preformatted structure and palette of icons allows students to focus on substance. This isn’t intended to cheapen the exercise, but to help teach lean principles at a pace that keeps students engaged.
I design simulations so they start with a challenge, even a failure, then follow up with success. One simulation I use in my supply chain courses is The Beer Distribution Game, a classic simulation of system dynamics created by MIT that’s been in use for 50 years. The game teaches the principle of the Bullwhip Effect and ends with students messing up the supply chain resulting in huge oscillations of overstocking and understocking inventory. Epic fail!
To make it stick, I run the simulation a second time implementing the principles of modern SCM that mitigate the Bullwhip Effect. The result is typically a 70-80% reduction in cost per pallet of beer distributed through the supply chain. Students get it. This contrast of methods demonstrates traditional versus Lean approaches. To allow time for two simulations, a spreadsheet is substituted for the traditional board game calculations reducing the total simulation time from about 90 minutes to 40.
I’m currently developing a simulation for Set-Based Concurrent Engineering (SBCE) in my lean product and process development course. This one is challenging since SBCE is not widely applied, and there are few examples of it. But I’m experimenting. In the simulation I run, I ask students to design the concept architecture of an electric vehicle powertrain. The challenge is to design four subsystems to achieve a given speed.
To eliminate waste, a workbook of calculations with one worksheet for each subsystem is provided. Students form teams of four and take on one subsystem each, working together to design a powertrain that results in the given speed. Within 30 minutes every team has a solution. What occurs is dozens of trial and error attempts of setpoint changes until the teams find a reasonable solution – classic point-based design iterations.
In the next class, we go through the concepts of Trade-off Curves and Knowledge Briefs with examples from literature and industry. SBCE is summarized again, and students are asked to use the SBCE approach in a second round of powertrain design. To eliminate waste, Knowledge Briefs are provided including design principles and trade-off curves. Also, the challenge is elevated to include not only a speed element, but also a minimum acceleration rate and the goal of optimal efficiency. At this point students begin to use the trade-off curves and have lively discussions about which setpoints should be optimized to achieve the goals. There remains a lot of trial and error, but students get the idea of a trade-off curve, knowledge briefs, and how SBCE could be a better way to design a system. There is much to improve in this simulation, but it’s proving to be a powerful learning experience.
What simulations, if any, do you use to teach lean thinking and practice?