I read somewhere that lazy people make the best inventors. I’ve also heard that necessity is the mother of all invention. Well, my mother raised a lazy inventor! I’m always looking for an easier way to do things and have in the past spent at least a day automating a data entry system when it would have only taken a few hours to enter the data manually. I may have missed on that one, but I did learn about data entry and some automation techniques that I have used successfully and more quickly for other tasks.
Tasks that are ripe for automation are frequently simple and repetitive. In the spring of 2006 I took over responsibility for teaching between two and three hundred engineering students per year how to program and operate CNC Machine tools to make parts and assemblies that they have designed. Over the years lab use has increased and now over one thousand students per year are doing work in the facility about half of them use one or more of the CNC machine tools. I’ve done this with two full time staff members plus countless student lab assistants and pear learning assistance. Even with that help it only works because we have automated a significant amount of the instruction.
How many times can you explain that the green button turns the machine on? For me it was about 64 times. By the time the 2ndbatch of 64 arrived I had written a 14 page quick guide that included information about starting the machine changing tools and jogging as well as instructions for loading code and running programs. The guide was deployed as a PDF document on computers located next to each machine tool. This was the beginning of the automation, but far from the end.
In those early days each class had 64 students divided into sections of 16 students and the course was offered 4 times per year. We have since expanded the enrolment to 72 students total but the overall layout remains the same. Each student has 4 hrs of lab per week for a total of 28 hrs of lab per term. With an average of 70 students per term times 28 hours per term times 4 terms per year that’s about 800 total hours of lab instruction and over 58,000 student hours of lab instruction that I’ve been responsible for.
In those almost 60,000 hrs, you might say I’ve learned a lot of students, but more importantly I’ve learned a lot about teaching and learning especially about lab instruction. The most important thing I’ve learned is that the best instructor is the one who has just completed the exercise they are teaching as long as they understand what they did and why, and the worst instructor is the one who is bored with the exercise, could do it with their eyes closed, and would rather just do it for the students because it would be faster.
How do you get the best instructor in front of the students? We did it by developing lab instructions that were simple and easy to understand (kind of like assembling furniture from IKEA) and then developing a system that allows the student who just finished the exercise to be the instructor for the student who just watched them do it. We call it watch-do-teach, wdt. I understand it is similar to the system used in medical schools where it is sometimes referred to as “watch one botch one.” Since operating a machine tool isn’t brain surgery we generally avoid the “botch one” aspect with simple clear instructions, and by asking the students to show understanding of the instructions and the concepts before they even start the watch step.
Our system has evolved over the years and has produced some amazing results. The first exposure is actually before the watch step and happens before the students arrive in lab. Students are expected to review pre-lab materials and the lab instructions and then answer questions in a pre-lab quiz usually by the Sunday evening before we complete a given exercise
Once students complete the quiz they add themselves to a wdt list by filling out a web based form. Once the students arrive in lab they are called to the machine tool or lab bench where the exercise is set up in the order they added themselves to the list.
To start an exercise the first two students are called up. The first does the exercise while the second reads the instructions to them (the instructions are deployed on a computer at the machine tool.) Once the first student has completed the exercise a third student is called up to watch, and the first student becomes the “instructor”, while the second student starts the do step of the process.
If a student is not available when they are called to the exercise a notation is made to the list indicating why they were unavailable and the next student is called. If the bottom of the list is reached, and there are still students who have not completed the exercise we begin again at the top of the list of course skipping anyone who has completed the exercise already.
The entire process is facilitated by a group of three students who have previously completed the labs. These three students are hired as pear learning assistants, PLAs. The group is composed of a lead PLA, this is someone with several terms of experience teaching labs; and two les experienced PLAs. The least experienced PLA is responsible for making sure that the students are called up in the correct order and that student are working on the correct exercises. The third PLA is responsible for starting the exercises and helping troubleshoot student problems both at the machine tools and while working on CAM exercises.
Students not actively working on one of the exercises are expected to be present in one of the two computer classrooms in the lab working on self paced CAM exercises, learning how to program the machine tools. When a student has a question about the CAM assignments they are encouraged to first ask their peers, and then find one of the PLAs.
This WDT system allows students who have never seen a machine tool before become safe and competent operators and programmers in just a few hours of “instruction”. It includes constant re-exposure to key concepts and the exercises are intended to build on each other.
