Undergraduate Research Experience in Remote Sensing - ACS

Chapter 3

Downloaded by HONG KONG UNIV SCIENCE TECHLGY on May 6, 2018 | https://pubs.acs.org Publication Date (Web): April 27, 2018 | doi: 10.1021/bk-2018-1276.ch003

Undergraduate Research Experience in Remote Sensing A. Kahl* Environmental Engineering, Penn State Greater Allegheny, 4000 University Dr., McKeesport, Pennsylvania 15132, United States *E-mail: [email protected].

The Multi-Campus Research Experience for Undergraduates (MC REU) is an initiative to increase undergraduate research at the Pennsylvania State University (Penn State), Greater Allegheny. The MC REU program supports Penn State undergraduate engineering students to conduct research with Penn State faculty. Students participating in the program complete a proposed engineering research project in conjunction with two Penn State faculty members; one from the student’s home campus and one faculty member based at University Park. The objectives of the MC REU are: (1) to promote undergraduate students participating in research early in their academic program to broaden their education and increase their chances of entering graduate studies; and (2) to promote mutual awareness and collaboration among faculty across the Commonwealth. This chapter details the results of two sessions of undergraduate research in remote sensing, with special emphasis on student engagement outside of the classroom and collaboration with faculty.

© 2018 American Chemical Society Roberts-Kirchhoff and Benvenuto; Environmental Chemistry: Undergraduate and Graduate Classroom, Laboratory, and Local ... ACS Symposium Series; American Chemical Society: Washington, DC, 2018.


Introduction The purpose of the research is to build and establish a network of data loggers across Western Pennsylvania to monitor water quality and observe salinization trends. Data loggers are simple sensors that collect and store information over time for a particular location. The problem with current water quality research is the lack of data across a focus area. If a large network can be easily and inexpensively built along streams and rivers in a focus area (in this case Western Pennsylvania), more insight can be found on the causes of poor water quality in drinking water sources. To do so, salinization measurements will give insight on overall water quality. Salinization can be found with a measure of conductivity, directly related to the concentration of total dissolved solids in the water (1). The problem with recent brand name data loggers is that they are too intricate and expensive for simple research purposes. What is needed to advance the current state of knowledge is a simple yet robust sensor that is cheap to build and easy to operate. Results from deploying this sensor will give an understanding on the behaviors of the dissolved solids present in surface water such as salt. Over time, the inexpensive data loggers have the potential to lead to a network of sensors blanketing Western Pennsylvania, therefore increasing awareness of water contamination issues. As the project is in its early stages, mapping the area where these sensors will be deployed has not yet occurred. Water quality data coupled with the emerging field of data science has the potential to expedite scientific research and inform decisions about resource allocation. One of the areas with the most potential for growth and innovation is that of the water sensing. Current water sensors are large, cumbersome to use and require specialized maintenance in order to gain reliable data sources. This limits the number of sensors citizen groups can deploy as well as the duration that they can be maintained. Smart systems, such as the internet of things (IOT) sensor network in this work can help track contaminants at the backyard level and act as first line avenues for data collection. The niche that citizen groups fill within the water quality data nexus is currently small due to the limited availability and accessibility of water quality sensors. Increasing data yields in a measurable way through inclusion of IOT sensors and optimization can build out the footprint of those community groups in a sustainable way. This in turn will build capacity within the network and provide a jumping off point for community revitalization efforts. Sensors for the IOT are growing in prevalence and availability. A Wall Street Journal article last year estimated that the IOT market could reach $1.7 trillion by 2020 (2). IOT technology has moved beyond indoor space and into the outdoors recently with a number of products and services such as the Edyn watering sensor. The Edyn garden sensor has 5 sensors. It measures temperature, humidity, light levels, soil moisture and soil nutrition (3). The Edyn probe functions by sending an electrical pulse into the soil and detecting how that pulse is affected by fertilizer and water using a technique that is identical to that used in commercial farming. It also includes extensive digital dictionaries indexing the compatibility, preferred conditions, and seasonal watering needs for thousands of plants. The current version of the Edyn is produced commercially and costs $99 50 Roberts-Kirchhoff and Benvenuto; Environmental Chemistry: Undergraduate and Graduate Classroom, Laboratory, and Local ... ACS Symposium Series; American Chemical Society: Washington, DC, 2018.


per sensor, which is still a substantial amount of money, particularly for a large network of sensors. There are currently open hardware low-cost data loggers for turbidity, but not other water-quality parameters such as salinity. An NSF-sponsored critical zone observatory (CZO) also includes multiple data loggers built with open-sourced hardware (Arduino) and monitoring equipment, but to our knowledge no conductivity measurements are recorded regularly and no sensor design was included in the design. The MC REU project is in its third year of existence. The REU program connects faculty and students early in their careers to help build a foundation of undergraduate research. Students spend most their time at their home commonwealth campus, with two weeks out of the ten-week experience in workshops with the entire cohort at University Park. Having two faculty mentors (one from each campus) allows students to make bridging connections and extend their research networks early in their undergraduate careers. It has been shown that students that participate in undergraduate research show increased interest in graduate study (4). A survey of researchers participating in NSF REUs showed a 29% increase in interest of students in pursuing a PhD after graduation following their undergraduate research experience (4). An emphasis of the MC REU program is for students to participate in the culture of research by experiencing faculty mentorship, presenting at the end of experience conference and writing about their research work. In this way, students broaden their education and increase their awareness of pathways to graduate education. Another emphasis of the MC REU program is to connect faculty from Commonwealth campuses to other faculty within Penn State. Faculty mentors collaborating on shared research goals with shared student workers promote awareness of Penn State resources and avenues for collaboration. A goal of the program is to spawn new research collaborations as well as to promote the use of shared resources for research.

Methods This project is based on the Arduino platform and uses Arduino Unos as its basis due to their wide availability and ease of use at an entry level. Arduino is an open source platform for building electronics. The Arduino system consists of a microcontroller or small circuit board, and software that is used to write and upload code to the microcontroller. Arduino code is based on C++, and is simple to learn and use, making it an ideal choice for an undergraduate research project. Two student teams worked over the course of two summer term periods to refine and test a basic sensor design. For the purpose of this exercise, each design was focused on sensing conductivity as the main goal. The first iteration of the sensor is a simple Arduino Uno that has three power sources, built in temperature sensor diodes, and a customizable protoboard. This sensor, called the Riffle, was originally produced by PublicLab as part of the Open Water Project. The Riffle can also be attached to a protoboard to increase 51

Roberts-Kirchhoff and Benvenuto; Environmental Chemistry: Undergraduate and Graduate Classroom, Laboratory, and Local ... ACS Symposium Series; American Chemical Society: Washington, DC, 2018.


its sensing capability. Both the Riffle and associated protoboard are shown in Figure 1. The Riffle can be powered with a lithium-ion battery, a button-cell battery, or a USB/microUSB port. The temperature is automatically logged on a microSD card for the Riffle. In order for the Riffle to measure conductivity, a circuit design capable of doing so was soldered onto the protoboard attachment. In order to make the Riffle compatible with a conductivity probe, the protoboard was adapted to include a sensor array called the Coqui. The Coquí (Figure 2) is designed with a probe that acts as a variable resistor.

Figure 1. Riffle Arduino board (top) and associated proto board (bottom).

Figure 2. Coqui sensor on protoboard. 52 Roberts-Kirchhoff and Benvenuto; Environmental Chemistry: Undergraduate and Graduate Classroom, Laboratory, and Local ... ACS Symposium Series; American Chemical Society: Washington, DC, 2018.


When the electrodes are placed into a solution, the solution has a specific conductance; therefore, acting as a resistor. Depending upon the voltage going through the circuit, the pitch of the piezo speaker varies. For example, if the probe is placed into water with high conductance, the pitch of the sound released from the piezo speaker increases. The speaker can be replaced with an LED light that will act similarly to the speaker. The light shines brighter the more conductive the sample is. The LED that is already in the circuit diagram in Figure 2 acts as an ‘on/off’ power indicator. To adapt the Coquí to the Riffle attachment, the piezo speaker is replaced with the analog read pin. The protoboard is designed where the top two rows are labeled connections that run to the data logger. The rest of the pins on the protoboard are connected vertically down the board. A diagram of the Coquí design for the protoboard can be seen in Figure 2. The LED is still used as a power indicator in the protoboard design. The protoboard is then connected to a simple nichrome wire probe which can be used to test the water sample. This simple device was then tested by the student to determine how well it performed compared to a traditional conductivity probe. The students then used these tools to evaluate prepared water samples. The prepared water sample consisted of tap water that had varying levels of salt present. During this challenge, students were required to answer the following questions: Does the new conductivity probe give good data compared to a traditional probe? Is the new conductivity probe easy to use? Could the design of the probe be improved? In what way? What are potential community uses for the conductivity probe? Questions were posed in oral form, following project discussion with faculty mentors in the eighth week of the REU experience. Students responded to these questions both orally and in the written form of a report. It was found that the Arduino based probe did not perform as well as the traditional probes within a reasonable margin of error (10-15%), likely due to interferences on the nichrome wire probe which lead to variation in the cell constant. As the comparison test was only performed one time, data is not included here. Students in future undergraduate research experiences will perform the comparison test multiple times to generate a larger data set for analysis, including statistics. Anecdotally, collecting and analyzing data helped to stimulate and sustain student interest in research, as students involved in the project were able to see their efforts manifest. Students made several suggestions regarding the design of the probe, the most common response being to make the probe more robust. This response was a valuable insight as the project continues to develop. For future work, undergraduate researchers will fabricate a housing to better protect the probe and reduce interferences. Regarding potential community uses for the probe, 53

Roberts-Kirchhoff and Benvenuto; Environmental Chemistry: Undergraduate and Graduate Classroom, Laboratory, and Local ... ACS Symposium Series; American Chemical Society: Washington, DC, 2018.

monitoring water quality downstream of industrial discharges and within local water bodies for fishermen were two popular responses. Students involved in the MC REU program were asked to produce weekly reports about their research experience, blog about topics related to undergraduate research and present a final poster at the closing research forum.


Discussion Close collaboration with faculty is one of the main goals of the program, which is fostered by the structure of the REU. As part of student engagement within the MC REU program, each student spends 8 weeks at their home campus and 2 weeks at the University Park Penn State campus. During this time, students visit laboratories on campus, attend sessions about career development and teambuilding, and meet with additional faculty and graduate students. Although working independently on a research project, students receive faculty support and instruction for several hours each week to help achieve their goals. This close collaboration is cited by students as the most valued asset of the program. Both sessions that have engaged with this program cite the close collaboration with faculty as well as the hands-on nature of the research activity as stimulating their interest in research. More specifically, the students were surveyed if they would continue doing undergraduate research. All responses were either agree or strongly agree. One commented that participating in the project “…helped me to see research as an avenue for a possible career that I had not considered before.” It was also noted in the comments portion of the poll that presenting their research in the closing forum helped them to better understand not only the material but to stimulate the interest of others in the audience in the growing field of remote sensing.

Conclusions This research experience has resulted in an engaged student experience that provides in-depth topic exploration and familiarity with complex material as well as providing greater engagement between faculty and students. Students benefited from the interaction with real world research problems as well as their own discoveries to provide enhanced understanding of the research process. Students responded overwhelmingly positively to this activity, and it is planned to continue to offer this research experience for students. For future work, students will map the area of Western Pennsylvania for sensor placement, and collect and interpret relevant water quality data using the sensors.

Acknowledgments The author would like to acknowledge the support of the Penn State Greater Allegheny community during preparation of this submission. 54 Roberts-Kirchhoff and Benvenuto; Environmental Chemistry: Undergraduate and Graduate Classroom, Laboratory, and Local ... ACS Symposium Series; American Chemical Society: Washington, DC, 2018.

References 1. 2. 3.


4.

Thomas, A. G. Specific Conductance as an Indicator of Total Dissolved Solids in Cold, Dilute Waters. Hydrol. Sci. J. 1986, 31 (1), 81–92. Norton, S. Internet of Things Market to Reach $1.7 Trillion by 2020. The Wall Street Journal, June 2, 2015. Flatow, I. The Blossoming Internet of Things for Your Garden. Science Friday, April 29, 2016. Russell, S. H.; Hancock, M. P.; McCullough, J. Benefits of Undergraduate Research Experiences. Science (Washington) 2007, 316 (5824), 548–549.

55 Roberts-Kirchhoff and Benvenuto; Environmental Chemistry: Undergraduate and Graduate Classroom, Laboratory, and Local ... ACS Symposium Series; American Chemical Society: Washington, DC, 2018.

Undergraduate Research Experience in Remote Sensing - ACS

Recommend Documents