Guided Modules Emphasizing Process-Based Troubleshooting Techniques Help Below-Average Performing Students Improve Instrumentation Skills

Instrumentation laboratory courses commonly focus on the design and development of novel technologies. Students work to develop the technical skills necessary to design and build circuit systems and their associated software, but often lack practice in troubleshooting skills and device testing and optimization. While the design of new devices is often more attractive to students, understanding how devices fail and learning structured ways to test and repair failure points is an important aspect of engineering design. To address this limitation, seven self-contained modules were developed to reinforce troubleshooting skills in a junior level bioinstrumentation course. These modules were not part of the course requirements but were presented as an additional tool to help students develop a logical, structured process for troubleshooting basic electronic circuits. Troubleshooting modules consisted of a hardware component (built using National Instruments prototyping boards and a variety of basic electronic components and transducers) and the associated software (National Instruments ELVIS and LabVIEW) necessary to test and identify the failure point of the electronic circuit. A step-by-step instruction manual was also included with each module to provide the technical specifications of the circuit and guide the students through a structured troubleshooting process. Final individual course grades and GPA scores from instrumentation-related core courses were both used to categorize below-average and above-average students in an effort to understand the effect of the course performance as well as the effect of their overall instrumentation skills on the observed response. Students that accessed the troubleshooting modules between the midterm and final laboratory exams were identified by the completion of a survey and served as the experimental group. Students that did not use the modules throughout the course served as the control group. Laboratory exams evaluate the students’ ability to design and troubleshoot electronic circuits and associated software and therefore were used to assess the impact of these changes. Midterm and final exam grades were compared between experimental and control groups for above and below average students using a two-way ANOVA. Due to the small class size, the impact of these modules was assessed over three semesters (fall 2015, fall 2016, fall 2017). The interaction effect between the use of modules and student performance was found to be statistically significant when below and above average students were categorized based on the final individual course grade (p=0.044) and when they were categorized based on the GPA scores in instrumentation-related courses (p=0.006). These results indicate that the effect on laboratory exam grades observed after using the troubleshooting modules will differ for belowaverage and above-average students. Our data suggests that using guided modules is an effective tool to improve hands-on troubleshooting skills, and that the observed response is greater for below-average students. Troubleshooting Skills in the Bioinstrumentation Laboratory Course Laboratory courses play an important role in engineering education, providing the students with opportunities to develop proficiency in experimental design, data analysis, the use of relevant equipment and tools, team work, communication skills and other practical skills relevant to the engineering practice. As design instruction has become more prevalent, engineering programs have incorporated design courses and embedded design projects at several stages of the undergraduate curriculum, including instructional laboratories. However, most of these courses focus on the early stages of the design process (i.e. problem identification, design criteria, research and brainstorming), with only some including a prototyping component and very few emphasizing the testing and iteration steps of the engineering design process. As a result, students rarely develop a structured process to test, debug and optimize equipment, components or prototypes. The Bioinstrumentation Laboratory (BIOE 385) is a required junior-level course that uses openended instruction to equip students with technical skills in electronic circuits and software. The course focuses on designing, building and testing two different devices: and optical immunoassay and an electromyogram-reflex device. The project-based structure of this lab provides students with the opportunity to apply some aspects of the engineering design process to solve problems in instrumentation. Students work on fabrication and optimization of discrete project components before they begin testing of the completed device. Because the course focuses on the development of biomedical technology, students practice the technical skills necessary to design and build circuit systems and their associated software, but rarely acquire significant experience in troubleshooting skills and device testing. While the students are gaining in-depth knowledge of the instrumentation topics covered in the lab, they often lack the ability to apply a structured troubleshooting process to repair or optimize an unfamiliar device or electronic circuit. Students become proficient in working with their specific devices, but when presented with new devices they are not able to extrapolate the process knowledge, even when failure points are similar to the ones they encounter in lab. Learning and practicing a structured process to test and repair failure points that can applied to any device is an important skill in the engineering practice. The Bioinstrumentation laboratory course has been modified in previous years to emphasize the troubleshooting process by: including course materials that describe common steps used when working with electronic circuits, providing additional testing tools and equipment for students to practice these skills outside of class, including a troubleshooting section as part of the final project report, and asking procedural questions in class to help students familiarize themselves with the troubleshooting process. Although some of these efforts have resulted in allocating more in-class time to device testing and optimization, most of these initiatives did not focus on troubleshooting techniques using a structured process (but rather on specific technical content), resulting in students using a trialand-error approach when troubleshooting their devices. Intervention and Assessment To address the observed limitations, seven self-contained modules were developed to reinforce troubleshooting skills in the bioinstrumentation course. These modules were not part of the course requirements but were presented as an additional tool to help students develop a logical, structured process for troubleshooting basic electronic circuits. Troubleshooting modules consisted of simple electronic circuits: a hardware component (built using the National Instruments ELVIS II engineering workstation and prototyping board and a variety of basic electronic components and transducers), and the associated software (National Instruments ELVIS and LabVIEW) necessary to test and identify the failure point of the modules. A step-bystep instruction manual was also included with each module to provide the technical specifications of the circuit and to guide students through the steps of the structured troubleshooting process. The impact of the troubleshooting modules was assessed using hands-on laboratory exam grades. Laboratory exams are designed to evaluate the students’ ability to build and troubleshoot electronic circuits and associated software and therefore represent a valid tool to assess the impact of these changes. Midterm and final exam grades were compared between experimental and control groups. Due to the small class size (34-41 students per year), the impact of these modules was assessed over three semesters (fall 2015, fall 2016, fall 2017). Students that did not use the modules during the semester served as the control group. Students that accessed the troubleshooting modules between the midterm and final laboratory exams were identified by the completion of a survey and used as the experimental group. Students in the experimental group were also asked to evaluate the effectiveness of the modules in terms of complexity, effectiveness as a learning tool, and the ease of use of the step-by-step manual associated with each module. To assess if the use of modules affected the measured response differently based on student performance, students were classified into low and high performing students. Final individual course grades in the bioinstrumentation laboratory course and GPA scores from all instrumentation-related core courses in the bioengineering undergraduate curriculum were both used to categorize below-average and above-average students. These two categories were used independently to analyze our results in an effort to understand the effect of the course performance as well as the effect of their overall instrumentation skills on the measured response. Changes in grades between midterm and final laboratory exams for students in the control and the experimental group were compared using an unpaired, 2-tailed t-test. A two way unbalanced analysis of variance (ANOVA) was conducted to evaluate the interaction between the use of troubleshooting modules and student performance (below-average vs. above-average students) on the laboratory exam grades, using both classifications as described above.