Progress 09/01/21 to 04/30/22

Outputs
Target Audience:In the western United States (US), there are large areas of dry rangeland, desert, and agricultural tracts that can generate blowing dust. Blowing dust is produced when the topsoil is eroded by high winds. High dust concentrations can cause brownouts on highways, leading to unsafe driving conditions. High dust concentrations also have serious human health effects in sensitive individuals. One particular size fraction of dust is known as "PM10" (that is, particulate matter with aerodynamic diameter less than 10 microns). PM10 is less than one fifth the diameter of a human hair and can travel long distances and be inhaled by humans causing harm to the respiratory tract (i.e. lungs), leading to chronic and acute sickness and even death. Because of these negative health impacts, the Environmental Protection Agency currently regulates PM10 as part of the National Ambient Air Quality Standards (NAAQS). Many dust-generating areas are near population centers, such as Phoenix, Salt Lake City, and cities in the Imperial Valley. In these areas, high PM10 concentrations have led to chronic public health issues. However, due to the size and complexity of the potential dust-generating areas paired with the long distances PM10 can travel, identifying areas that contribute degrading the public health is a difficult problem. As a means of identifying dust-generating areas, we propose the development of a Wind Erosion Quantification Sensor (WEQS), which will measure horizontal soil particle motion. Moving soil particles are the major cause of dust and PM10 generation; therefore, measuring soil particle motion provides an excellent means of assessing dust generation potential. Current methods to measure particle motion are expensive, difficult to maintain, and/or require specialized knowledge. To develop the WEQS, we will be starting with a known soil particle collection device, the Cox Sand Catcher. As soil particles are collected, they will be detected with a laser diode device that will detect interruptions in the light path. An integrated weighing device will work with the laser diode device to measure the sand motion. This information will be stored and processed on site using a microprocessor and then transmitted to a Cloud storage platform. The onsite data processing and data transmission will allow for the devices to be autonomous and capable of being deployed to remote locations. The simplicity of the WEQS will make it affordable and easy to deploy so that a variety of landowners (e.g., federal land managers, local governments, or ranchers) can purchase and use these to identify dust generating areas on their land. Once identified, the dust-generating areas can be targeted for mitigation, thereby reducing the amount of dust and PM10 generated. Because of the easy deployment, data accessibility, and affordability, the development of the WEQS has the potential to become a useful tool in ongoing programs to reduce the extent of wind-blown soil erosion, and its associated high PM10 concentrations, across the arid lands of the Western US. Changes/Problems:There are two major challenges. The first major challenge continues to be the development of a low cost power system. Since the last reporting period, we continued to try differenct charge regulation systems, but they do not work to adequately power the system. We have temporarily settled on a medium-cost power system that works to power the system even during the winter in Portland, Oregon. This would increase the cost of the final instrument; however, it will still be much more affordable than the current commercially available options. The other challenge has been COVID-19. This has made progress slow as we can only have a limited number of individuals in the working space at a time. Without the hands on collaboration that is normal for such a project, the development has been slower. The EPL also still has limited access due to COVID-19 precautions, which limited the access to board development and related resources. What opportunities for training and professional development has the project provided?The project has been developed as the joint effort of three early career engineers and scientists. Through the guidance provided on this project, these individuals have developed programming and design skills. They have learned how to use and employee programs, such as EagleCAD and Fusion 360, that will be useful for their careers. How have the results been disseminated to communities of interest? Nothing Reported What do you plan to do during the next reporting period to accomplish the goals?The next efforts will be focused on solving the issues related to the low cost power system and then creating a full prototype that is robust enough for field testing and will be manufacturing-ready. The major impediment to progress in the full prototype development has been the closure of the ElectronicsPrototyping Lab (EPL) at Portland State University due to COVID-19 precautions. The EPL was supposed to openfor limited use as ofJanuary 1, 2021; however, use is still restricted as the pandemic continues. We have proposed subcontracting with Able Sensor to be able to have better access to equipment needed to develop a prototype. Additionally, Able Sensor would be able to provided guidance for what is needed to make a prototype that is manufacturing-ready.

Impacts
What was accomplished under these goals? The major accomplishment thus far was creating a tipping bucket that works with sand,tips at several grams, and fits within a modified Cox Sand Catcher. Some of the challenges were: 1) getting the bucket to tip up and down, 2) preventing sand from bouncing out of the top of the bucket, and 3) preventing the sand from slipping out of the bucket before the tip occurred, 4) creating a base that would hold the tipping bucket, funnel, and OGS devices, and 5) designing a modified Cox Sand Catcher. All of these challenges have been overcome with the current tipping bucket design. These portions of the design satisfy the objectives 2, 3, 5, and 6. The low frequency sand collection device (Cox Sand Catcher)has been modified to accomodate a funnel and the tipping bucket platform and all the electronics. The modified Cox Sand Catcher with the embedded funnel is currently undergoing field testing to determine how well it compares to the standard Cox Sand Catcher. This was listed above as project objective 2. The tipping bucket currently tips at several grams of sand. This will be a good set point for usage within many of the known environments in the United States. Further assessments need to be done to determine the average and standard deviation of the sand mass per tip. This satisfies object 3. The interface for recording the bucket tips and storing date (project objectives 4 and 5) is partially developed. We currently have an Arduino microprocessor recordsthe bucket tips and detects the OGS interrupts. This works with DC power from the solar power system. Now, we need to re-integrate the temp/RH sensor recordings and the radio transmission. The low-cost power system development still proves to be more difficult to build than originally thought. We are still working on this; however, we have a medium cost power system that works for now and is allowing us to focus efforts on developing the core WEQS. The prototype is nearly complete with the exception of the power system. The main challenge now is to create a more robust prototype that is manufacturer ready. As soon as the robust prototype is ready, it will be installed in our two field testing locations. One of these currently has themodified CSCs collocated with the standard CSC and a Sensit.

Publications

Progress 09/01/20 to 04/30/22

Outputs
Target Audience:The program has targeted the development ofan instrument that could be used by Federal and State agencies (e.g., United States Department of Agriculture, Bureau of Land Management, Imperial County Air Pollution Control District) and private landowners. The instrument will havea user-friendly installation so that someone with general, but not specialized, technical knowledge would be able to install the instrument autonomously. The economical price point increases the target audience beyond the current technology as more monitors could be deployed at a larger number of locations, while remaining within specific budgetary constraints. Changes/Problems:There have been threemajor challenges. The first major challenge is the development of a low cost power system. Since the last reporting period, we continued to try differenct charge regulation systems, but they do not work to adequately power the system. We have temporarily settled on a medium-cost power system that works to power the system even during the winter in Portland, Oregon. This would increase the cost of the final instrument; however, it will still be much more affordable than the current commercially available options. The second challenge has been COVID-19. This has made progress slow as we can only have a limited number of individuals in the working space at a time. Without the hands on collaboration that is normal for such a project, the development has been slower. The EPL also still has limited access due to COVID-19 precautions, which limited the access to board development and related resources. The third challenge was the design of the tipping bucket. Because of the angle of repose of sand, the geometry used for rain tipping buckets did not work. Then we found a published study that had a bucket geometry specific for sand; however, it was much larger than we wanted. Scaling the bucket down to a size that could fit in the modified Cox Sand Catcher and tip at several grams was a challenge. Then, it was a challenge to detect the tips. rain tipping buckets often use magnetic sensing, yet this was not a good option for us. We settled on another set of OGDs, which needed to then be integrated into the board design separate from the funnel OGDs. What opportunities for training and professional development has the project provided?Throughout the course of the project, we have employed three students (two graduate and one undergraduate). This has been a valuable learning opportunity for them. They have been able to apply the skills learned in school to a real-world design challenge. Under the guidance of the project manager and our subcontractor (Able Sensor), they have been able to develop their skills in instrument design, board design, and programming. How have the results been disseminated to communities of interest?We have held preliminary discussions with strategic partners as part of the effort to assess market viability. These discussions have been held via email or on the phone. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? The major accomplishment thus far was creating a tipping bucket that works with sand, tips at 2.4 grams, and fits within a modified Cox Sand Catcher. Some of the challenges were: 1) getting the bucket to tip up and down, 2) preventing sand from bouncing out of the top of the bucket, and 3) preventing the sand from slipping out of the bucket before the tip occurred, 4) creating a base that would hold the tipping bucket, funnel, and OGS devices, and 5) designing a modified Cox Sand Catcher. All of these challenges have been overcome with the current tipping bucket design. These portions of the design satisfy the objectives 2, 3, 5, and 6. The low frequency sand collection device (Cox Sand Catcher) has been modified to accomodate a funnel and the tipping bucket platform and all the electronics. The modified Cox Sand Catcher with the embedded funnel is currently undergoing field testing to determine how well it compares to the standard Cox Sand Catcher. This was listed above as project objective 2. Initial feedback from the field indicates that the original funnel had too narrow of a neck and sometimes resulted in sand getting stuck. After the conclusion of the performance period, we will be deploying an updated funnel to the field for further testing. The tipping bucket currently tips at 2.4 grams of sand. This will be a good set point for usage within many of the known environments in the United States. This average was obtained by measuring 10 test tips on each side of the bucket. The standard deviation of the 20 test tips was 0.2 grams. Additionally, there was no statistical difference between the mass measured on the two sides of the bucket. This satisfies object 3. The interface for recording the bucket tips and storing date (project objectives 4 and 5) is developed and working as intended. We currently have an Arduino microprocessor records the bucket tips and detects the OGDinterrupts. This works with DC power from the solar power system. Now, we need to re-integrate the temp/RH sensor recordings and the radio transmission. The low-cost power system development still proves to be more difficult to build than originally thought. We are still workingon this; however, we have a medium cost power system that works for now and is allowing us to focus efforts on developing the core WEQS. The prototype iscomplete with the exception of the low-cost power system. The main challenge now is to create a more robust prototype that is manufacturer ready. As soon as the robust prototype is ready, it will be installed in our two field testing locations. One of these currently has the modified CSCs collocated with the standard CSC and a Sensit.

Publications

Progress 09/01/20 to 04/30/21

Outputs
Target Audience: Nothing Reported Changes/Problems:There have been two major challenge. The first major challenge was the development of a low cost power system. We have tried several different charge regulation systems, but they do not work to adequately power the system. Now that the EPL is open, we will have additional guidance from the lab manager and we will be able to try several more sophisticated power systems. The other challenge was COVID-19. This has made progress slow as we can only have a limited number of individuals in the working space at a time. Without the hands on collaboration that is normal for such a project, the development has been slower. The EPL was also closed due to COVID-19 precautions, which limited the access to board development and related resources. What opportunities for training and professional development has the project provided?The project has been developed as the joint effort of three early career engineers and scientists. Through the guidance provided on this project, these individuals have developed programming and design skills. They have learned how to use and employee programs, such as EagleCAD and Fusion 360, thatwill be useful for their careers. How have the results been disseminated to communities of interest? Nothing Reported What do you plan to do during the next reporting period to accomplish the goals?The next efforts will be focused on solving the issues related to the low cost power system and then creating a full prototype for field testing. The major impediment to progress in the full prototype development has been the closure of the Electronics Prototyping Lab (EPL) at Portland State University due to COVID-19 precautions. The EPL is opened for limited use as of January 1, 2021. With the opening of the EPL, progress towards the prototype development will be accelerated.

Impacts
What was accomplished under these goals? The major accomplishment thus far was creating a tipping bucket that would work with sand. Some of the challenges were: 1)getting the bucket to tip up and down, 2) preventing sand from bouncing out of the top of the bucket, and 3) preventing the sand from slipping out of the bucket before the tip occurred. All of these challenges have been overcome with the current tipping bucket design. This was listed above as project objective 2. The low frequency sand collection device has been modified to accomodate a funnel. Currently, the device is being modified further to include the tipping bucket platform and all the electronics. This was listed above as project objective 2. The interface for recording the bucket tips and storing date (project objective 3) is partially developed. We currently have an Arduino microprocessor that will record the bucket tips; however, this needs to be modified to still work if one of the tip OGS devices fails. Additionally, the current model is made to be powered from AC power, which will not be possible in the field. The low-cost power system development has provided to be more difficult than originally thought. The development of the low-cost power system is an additional project objective that is currently being worked on. Two OGS devices have been embedded in the delivery tube that is between the funnel and the tipping bucket. The information from these is being recorded by the Arduino microprocessor. The next challenge will be to determine how to create one file that records both tipping bucket activity and OGS activity. This was listed above as project objective 5. The prototype is nearly complete with the exception of the power system. In the next two to three weeks, we plan to have a prototype ready for initial field testing (project objective 7). While this is being developed, a second prototype will be used to refine the design to achieve repeatability in the amount of sand collected per tip (project objective 3).

Publications