Using Experiential Learning to Teach Office Ergonomics in the Undergraduate Classroom

Knowledge of contemporary issues is an important component of every industrial engineering undergraduate student’s curriculum. As professors in Industrial Engineering, it is our duty to continually update our courses to meet the changing needs of our students. The traditional topics of an industrial engineer have historically focused on the manufacturing and product industry. Specifically in the area of workplace design, the legacy workplace was impacted by the industrial revolution and corresponding tools for improvement in productivity. However, the knowledge economy and the explosion of information technology have changed the typical workplace. This paper demonstrates an office ergonomics productivity evaluation that was incorporated into an undergraduate ergonomics class as a lab experiment. The experiment integrated a collection of topics and allowed students to learn in an experiential fashion. The lab experiment covered workplace design by comparing three potential computer workstation configurations: the traditional seated design, a standing design, and a treadmill walk station. The experiment quantified productivity with an input task based on Fitts's Tapping Task, another basic topic of ergonomics curriculum. The data for the experiment followed a factorial experimental design and were analyzed using multiple regression and analysis of variance, thus combining additional topics. The experiment also allowed students to relate the results of the experiment to the design problem. The results of the research show that walking adversely affects productivity yet comparing seated and standing postures yields mixed results. For more simple tasks, the ideal posture is sitting while for more complex tasks the worker should be standing for improved productivity. The ergonomics class was enhanced by the discussions about the tradeoffs of various factors in workplace designs that are relevant in the application of this topic to real-world experiences. 1. Background Faculty members teach the importance of contemporary topics for undergraduate engineering students by sharing research in various ways. Active participation as a research assistant with a funded faculty member represents one direct method of immersing students into research. A lack of substantial and programmatic undergraduate research opportunities limits the impact of this hands on research experience to a handful of students who are funded by individual faculty research programs. Including research methods and results as part of the lecture in a traditional classroom comprises an indirect method of sharing faculty research. The impact of this method extends to an entire class of students and it provides a large number of undergraduates the opportunity to hear about a carefully designed research experience. Achieving active student engagement in a the classroom can enhance the quantity and quality of learning that will result from the experience. This paper describes a direct method of teaching ergonomics topics by incorporating a research study into a classroom laboratory experience. This results in a hands-on, active learning experience that will impact all students in the class. In addition to learning research methods by participation, this approach incorporates additional topics and broader contemporary topics. 2. Purpose The traditional ergonomics syllabus has focused on the physical requirements of manual labor workers. While manufacturing and other jobs requiring physical labor remain vital components in the workforce, many developed countries have transitioned to a knowledge economy. By 2003, more than half of all workers in the United States used a computer and the number of computers in use worldwide exceeded the 1 billion mark in 2008. Rather than bending, lifting and assembling in a factory setting, workers now look at a computer monitor, move and click a mouse and type on a keyboard while sitting at a desk. Computer based work has led to new sources and types of worker health problems including an increased rate of cumulative trauma disorders. This necessitates changes in the ergonomics curriculum to include the impact of the new work environment on productivity as well as health & safety. Determining the human factors that affect productivity and safety in the workplace has a become primary goal in the ergonomics classroom. To address health and safety issues resulting from computer based work, product designers have developed new styles of workstations. The treadmill workstation is a relatively new and novel approach to get office workers to stand up and move while on the job. However, the impact of the treadmill workstation on worker productivity and safety has not been fully explored. Studies have shown there are many confounding variables which makes the impact of the treadmill workstation on worker productivity an ideal topic for discussion and debate. 3. Method This paper contains the results of a research study conducted in an ergonomics class that has both a lecture and a laboratory component. During the one semester class, students will participate in eight different lab experiments with a written lab report requirement. Lab topics include anthropometry, strength, and hand tool design among others. Lab experiments are rotated and refreshed to keep the class up to date. The lab topic included in this paper tests the hypothesis that computer workstation has an impact on productivity. In the lab, students compare three computer workstation designs where worker productivity is measured using a computer input task based on Fitts’s Tapping Task. As background, the Hick-Hyman equation and Fitts’s Tapping Task are discussed during the lecture prior to this lab. In this lab, as is the case with the other labs in the course, the students serve as both subjects and data analysts for the experiment. The lab experiment utilizes three computer workstations. One computer workstation is a traditional desk with the worker in a sitting posture. A second computer workstation integrates a treadmill into the worker’s environment allowing the worker to assume a walking posture at a speed less than 2 mph. When discussing the lab setup, it was noted that comparing the traditional sitting workstation to the treadmill workstation introduced two design differences between the workstations: sitting versus standing and stationary versus movement and that these two differences are confounded. This suggested the need for a third workstation design to separate the two effects; therefore, the standup workstation was added to the study that allowed the subject to work in a standing posture without walking. Figure 1 shows a study participant at each of the three workstations. Figure 1: Study Subject Performing Input Task at Sitting, Walking and Standing Workstations The participants in the study consisted of the eleven students in the class. After conducting the experiment, each student analyzed the resultant data and produced a written lab report. During the lab, the students had to identify variables that might affect the results and control those variables as much as possible. For example, to keep the mouse in the same relative position, the height of the standing and walking workstations needed adjustment to compensate for the varying height of the students. Fortunately, the students identified many constants in the study. For example, the participants all had experience using computers with a mouse, they all owned their own personal computer, were all right handed with no physical disabilities. A discussion also noted that the study only contained younger people as subjects who may perform differently than older subjects which could potentially introduce a bias into the results. Students performed a computer input task using a mouse as the input device in each of the three workstations. The computer task consisted of a series of point and click exercises to illustrate the Fitt’s Tapping Task. The goal of the task was to perform the clicks as quickly as possible. Students performed two trials at each of the three workstations (subjects used workstations in different orders to randomize learning during the study) yielding 24 time values for each subject. This results in two replicates of a 2x2x3 full factorial design in the Distance (Close and Far), Size (Small and Large) and Workstation (Sit, Stand and Walk) factors. This allowed students to gain a better grasp of experimental design concepts by participating in the various configurations of the design factors. Figure 2 shows the Lab Handout that also served as a data sheet. Computer Input Efficiency or Fitts’s Tapping Task Lab The purpose of this lab is to examine the effects of target size, spacing, posture and movement on the amount of time it takes to accurately tap alternately between two targets. Theory suggests that the process obeys Fitts’s Law. Method: There are several computer test stations in the lab. Each computer may be set up with a workspace that requires the subject to modify their posture (e.g. sit, stand, walk, other) or utilize a unique input device (e.g. mouse, trackball, joystick, tablet, other) while performing a standard task. Variables Dependent: Movement Time in seconds Independent: Distance between target centers in inches (Close Spacing = 2, Far Spacing = 4) Target Width in inches (Small button = 0.5, Large button = 1) Posture (Sit, Stand, Walk) Analysis: Perform appropriate statistical analysis to determine what independent variable has the most effect on movement time. Use Hicks-‐Hyman regression equation to predict movement time for various levels of difficulty. What assumptions must be made to use regression analysis rather than ANOVA? Conclusions: Discuss your findings in terms of Fitt’s Law and the implications your findings have for the design of work. Figure 2. Lab Handout 4. Results and Conclusions After the lab session, the students analyzed the class data and interpr